Organogenesis Research Papers - Academia.edu (original) (raw)

An efficient regeneration system, direct and indirect organogenesis, was developed for Curculigo orchioides-an endangered medicinal herb. Shoot multiples were initiated from in vitro grown leaf explants through direct organogenesis on... more

An efficient regeneration system, direct and indirect organogenesis, was developed for Curculigo orchioides-an endangered medicinal herb. Shoot multiples were initiated from in vitro grown leaf explants through direct organogenesis on Murashige and Skoog’s (MS) medium containing ½ strength nitrogen salts and 0.44 μM BA. Almost 10 shoots were obtained per leaf explant (1 cm long). On the other hand MS medium with full strength nitrogen salts and 2.22 μM BA, stimulated callus formation and almost 8 shoots were obtained per leaf explant (1 cm long ). Comparative study of shoots regenerated directly or through callus revealed differences in number of leaves, shoot length, root length, fresh and dry weight

The neural consequences of early-life exposure to methylphenidate (MPH; Ritalin) are of great interest given the widespread, and sometimes inappropriate, use in children. Here we examine the impact of juvenile MPH exposure on adult... more

The neural consequences of early-life exposure to methylphenidate (MPH; Ritalin) are of great interest given the widespread, and sometimes inappropriate, use in children. Here we examine the impact of juvenile MPH exposure on adult hippocampal neurogenesis. Methods: Rats received MPH (2.0 mg/kg, intraperitoneal, twice daily) or saline (SAL) during preadolescence (postnatal days 20 -35). Hippocampal cell proliferation (Experiment 1), neurogenesis (Experiment 2), and stress-induced changes in cell proliferation (Experiment 3) were assessed at several developmental stages including adulthood. Results: Juvenile exposure to MPH did not alter proliferation at any developmental time point relative to control rats; however, exposure to MPH significantly decreased the long-term survival of newborn cells in adult rats, particularly in the temporal hippocampus. Although MPH-treated rats had higher levels of corticosterone after restraint stress, they did not show the expected greater decrease in hippocampal cell proliferation relative to control animals. Conclusions: Early-life exposure to MPH inhibits the survival of adult-generated neurons in the temporal hippocampus and may reduce progenitor sensitivity to corticosterone-induced decreases in proliferation. These findings suggest that decreased adult neurogenesis is an enduring consequence of early-life exposure to MPH and are discussed for their relevance to humans.

LINGO-1 is a CNS-specific protein and a functional component of the NgR1/p75/LINGO-1 and NgR1/TAJ(TROY)/LINGO-1 signaling complexes that mediate inhibition of axonal outgrowth. These receptor complexes mediate the axonal growth inhibitory... more

LINGO-1 is a CNS-specific protein and a functional component of the NgR1/p75/LINGO-1 and NgR1/TAJ(TROY)/LINGO-1 signaling complexes that mediate inhibition of axonal outgrowth. These receptor complexes mediate the axonal growth inhibitory effects of Nogo, myelin-associated glycoprotein (MAG) and oligodendrocyte-myelin glycoprotein (OMgp) via RhoA activation. Soluble LINGO-1 (LINGO-1-Fc), which acts as an antagonist of these pathways by blocking LINGO-1 binding to NgR1, was administered to rats after dorsal or lateral hemisection of the spinal cord. LINGO-1-Fc treatment significantly improved functional recovery, promoted axonal sprouting and decreased RhoA activation and increased oligodendrocyte and neuronal survival after either rubrospinal or corticospinal tract transection. These experiments demonstrate an important role for LINGO-1 in modulating axonal outgrowth in vivo and that treatment with LINGO-1-Fc can significantly enhance recovery after spinal cord injury.

Cadherin-11 (cad-11) is primarily a mesenchymal cadherin that appears in delaminating neural crest cells. Its expression correlates with morphogenetic events and the pattern has been studied in mouse, rat and Xenopus embryos, but not... more

Cadherin-11 (cad-11) is primarily a mesenchymal cadherin that appears in delaminating neural crest cells. Its expression correlates with morphogenetic events and the pattern has been studied in mouse, rat and Xenopus embryos, but not during avian organogenesis. Our purpose was to investigate this pattern in the chick embryo during organogenesis using immunolocalization and in situ hybridization. Cad-11 was expressed in mesenchyme around the pharynx and aortic arches, eyes, auditory vesicles, lung buds, stomach, and nasal placodes. Neural expression included some cranial ganglia and also new neuroepithelium within the tail bud region undergoing secondary neurulation. We also found expression in epithelia of the developing circulatory and digestive organs. The limb buds, pineal rudiment and mesonephros were also positive. Cad-11 expression became more widespread with development. Our findings support the role of cad-11 as a mesenchymal cadherin, but provide evidence for a wider role t...

The ubiquitin proteasome system (UPS) is the main proteolytic system of cells. Recent evidence suggests that the UPS plays a regulatory role in regeneration processes. Here, we explore the possibility that the UPS is involved during... more

The ubiquitin proteasome system (UPS) is the main proteolytic system of cells. Recent evidence suggests that the UPS plays a regulatory role in regeneration processes. Here, we explore the possibility that the UPS is involved during intestinal regeneration of the sea cucumber Holothuria glaberrima. These organisms can regenerate most of their digestive tract following a process of evisceration. Initially, we identified components of H. glaberrima UPS, including sequences for Rpn10, β3, and ubiquitin-RPL40. Predicted proteins from the mRNA sequences showed high degree of conservation that ranged from 60% (Rpn10) to 98% (Ub-RPL40). Microarrays and RT-PCR experiments showed that these genes were upregulated during intestinal regeneration. In addition, we demonstrated expression of alpha 20S proteasome subunits and ubiquitinated proteins during intestinal regeneration and detected them in the epithelium and connective tissue of the regenerating intestine. Finally, the intestinal regener...

The thesis advanced in this essay is that stem cells-particularly those in the nervous system-are components in a series of inborn 'programs' that not only ensure normal development, but persist throughout life so as to maintain... more

The thesis advanced in this essay is that stem cells-particularly those in the nervous system-are components in a series of inborn 'programs' that not only ensure normal development, but persist throughout life so as to maintain homeostasis in the face of perturbations-both small and great. These programs encode what has come to be called 'plasticity'. The stem cell is one of the repositories of this plasticity. This review examines the evidence that interaction between the neural stem cell (as a prototypical somatic stem cell) and the developing or injured brain is a dynamic, complex, ongoing reciprocal set of interactions where both entities are constantly in flux. We suggest that this interaction can be viewed almost from a 'systems biology' vantage point. We further advance the notion that clones of exogenous stem cells in transplantation paradigms may not only be viewed for their therapeutic potential, but also as biological tools for 'interrogating' the normal or abnormal central nervous system environment, indicating what salient cues (among the many present) are actually guiding the expression of these 'programs'; in other words, using the stem cell as a 'reporter cell'. Based on this type of analysis, we suggest some of the relevant molecular pathways responsible for this 'cross-talk' which, in turn, lead to proliferation, migration, cell genesis, trophic support, protection, guidance, detoxification, rescue, etc. This type of developmental insight, we propose, is required for the development of therapeutic strategies for neurodegenerative disease and other nervous system afflictions in humans. Understanding the relevant molecular pathways of stem cell repair phenotype should be a priority, in our view, for the entire stem cell field.

Many available methodologies for in vitro regeneration of commercial tomato varieties promote not only the production of normal shoots but also individual leaves, shoots without apical meristems and vitrified structures. All these... more

Many available methodologies for in vitro regeneration of commercial tomato varieties promote not only the production of normal shoots but also individual leaves, shoots without apical meristems and vitrified structures. All these abnormal formations influence and diminish the regeneration efficiency. At the basis of this phenomenon lies callus development. We optimized an alternative procedure by which the regeneration occurs without abnormal shoot formation. The portion including the proximal part of hypocotyls and the radicle was cultured on medium consisting of Murashige and Skoog salts, 4 mg/L thiamine, 100 mg/L mio-inositol and 3% sucrose. After twothree weeks, 60% explants showed adventitious shoot formation. No changes in the morphological characteristics of regenerated plants and fruits were observed as compared with parents. Karyotypic analysis of regenerated plants showed no variations in chromosome number. The optimized procedure offers the advantage of tomato plant regeneration avoiding callus formation, which enables normal plant recovery with an efficiency ranging from 1.45 ± 0.05 to 2.57 ± 0.06 shoots per explant in Campbell-28, Amalia, Lignon, and Floradel cultivars.

Some morphological characteristics of the variable thyroid ima artery were investigated on the injected fetal arteries and explained on their 106 static images. Thyroid ima artery of different origin was proven in 18 (16.9%) cases. With... more

Some morphological characteristics of the variable thyroid ima artery were investigated on the injected fetal arteries and explained on their 106 static images. Thyroid ima artery of different origin was proven in 18 (16.9%) cases. With respect to the vascular sources of the investigated artery, the branching of the brachiocephalic trunk and right common carotid artery was found in 72.1% of the cases. At the same time, the thyroid ima and superior or inferior thyroid arteries were obvious in all cases, as well as the presence of single or multiple variations and abnormalities of neighbouring arteries in 38.8% of the cases. No major anatomical difference was noted between the fetal form of the variable thyroid artery reported in this paper and the postnatal form reviewed from the literature. Thyroid ima artery probably represents an example of the arterial self-differentiation and induced differentiation of the unilateral vascular trunk.

Paper ini akan membahas secara komprehensif Organel tumbuhan yang sesuai dengan buku Biologi Kurikulum 2013 yang mencakup : 1) Proses pembentukan organ tumbuhan (Organogenesis), 1a) Organogenesis Batang, 1b) Organogenesis Daun, 1c)... more

Paper ini akan membahas secara komprehensif Organel tumbuhan yang sesuai dengan buku Biologi Kurikulum 2013 yang mencakup :

  1. Proses pembentukan organ tumbuhan (Organogenesis),
    1a) Organogenesis Batang,
    1b) Organogenesis Daun,
    1c) Organogenesis Bunga,
    1d) Organogenesis Buah,
    1d1) Polinasi
    1d2) Buah Sederhana
    1d3) Buah Agregat
    1d4) Buah Aksesori
    1d5) Buah Banyak
  2. Meristem tumbuhan,
  3. Fungsi dari bagian-bagian tumbuhan

We present efficient protocols for the regeneration of fertile plants from corm explants of Hypoxis hemerocallidea Fisch. & C. A. Mey. landrace Gaza, either by direct multiple shoot formation or via shoot organogenesis from corm-derived... more

We present efficient protocols for the regeneration of fertile plants from corm explants of Hypoxis hemerocallidea Fisch. & C. A. Mey. landrace Gaza, either by direct multiple shoot formation or via shoot organogenesis from corm-derived calluses. The regeneration efficiency depended on plant growth regulator concentrations and combinations. Multiple direct shoot formation with high frequency (100% with 5-8 shoots/explant) was obtained on a basal medium (BM) supplemented with 3 mg/l kinetin (BM1). However, efficient indirect regeneration occurred when corm explants were first plated on callus induction medium (BM2) with high kinetin (3 mg/l) and naphthalene acetic acid (NAA 1 mg/l), and then transferred to shoot inducing medium (BM3) containing BA (1.5 mg/l) and NAA (0.5 mg/l). Shoot regeneration frequency was 100% and 30-35 shoots per explant were obtained. The regenerated shoots were rooted on a root inducing medium (BM4) containing NAA (0.1 mg/l). Rooted plantlets were transferred to the greenhouse. The regenerants were morphologically normal and fertile. Flow cytometric analyses and chloroplast counts of guard cells suggested that the regenerants were diploid. Efficient cloning protocols described here, have the potential not only to substantially reduce the pressure on natural populations but also for wider biotechnological applications of Hypoxis hemerocallidea-an endangered medicinal plant.

The Fras1 and Frem extracellular matrix proteins play critical roles in epithelial-mesenchymal interaction during embryonic development. Loss of function in humans results in a recessive embryonic blistering disorder called Fraser... more

The Fras1 and Frem extracellular matrix proteins play critical roles in epithelial-mesenchymal interaction during embryonic development. Loss of function in humans results in a recessive embryonic blistering disorder called Fraser syndrome. Inactivation of these proteins, or the proteins with which they interact (e.g., Grip1) has also been shown to underlie members of the 'bleb' family of classic mouse mutants which provide a valuable model of Fraser syndrome. Recent studies supporting direct interactions between the Fras1 and Frem proteins, combined with more rigorous elucidation of their developmental regulation, have shed new light on their activity. We summarize the findings to date, bringing new insight into their role in the regulation of epidermal-basement membrane adhesion and organogenesis during development.

The signaling component of the mammalian Fibroblast Growth Factor (FGF) family is comprised of eighteen secreted proteins that interact with four signaling tyrosine kinase FGF receptors (FGFRs). Interaction of FGF ligands with their... more

The signaling component of the mammalian Fibroblast Growth Factor (FGF) family is comprised of eighteen secreted proteins that interact with four signaling tyrosine kinase FGF receptors (FGFRs). Interaction of FGF ligands with their signaling receptors is regulated by protein or proteoglycan cofactors and by extracellular binding proteins. Activated FGFRs phosphorylate specific tyrosine residues that mediate interaction with cytosolic adaptor proteins and the RAS-MAPK, PI3K-AKT, PLCγ, and STAT intracellular signaling pathways. Four structurally related intracellular non-signaling FGFs interact with and regulate the family of voltage gated sodium channels. Members of the FGF family function in the earliest stages of embryonic development and during organogenesis to maintain progenitor cells and mediate their growth, differentiation, survival, and patterning. FGFs also have roles in adult tissues where they mediate metabolic functions, tissue repair, and regeneration, often by reactiv...

Présenté par Michel Thellier Résumé-Devant le rythme accru de la dégradation de la palmeraie marocaine, son repeuplement dépend de la plantation de vitroplants. Pour évaluer le comportement de ces derniers, une étude morphologique de... more

Présenté par Michel Thellier Résumé-Devant le rythme accru de la dégradation de la palmeraie marocaine, son repeuplement dépend de la plantation de vitroplants. Pour évaluer le comportement de ces derniers, une étude morphologique de clones de palmier dattier, obtenus par organogenèse à partir de jeunes feuilles de coeurs de rejets, a été réalisée sur 92 vitroplants issus de trois cultivars (Boufeggous, Jihel et Bouskri) et de deux saïrs (Saïr 16bis et 35). Les résultats de l'analyse en composante principale (ACP) de 34 variables morphologiques de l'appareil végétatif et reproducteur et ceux de la classification hiérarchique nous ont permis de mettre en évidence une hétérogénéité intraclonale de ces vitroplants au sein de chaque cultivar et saïr. Un certain nombre de caractères ont été retenus comme étant les caractères les plus discriminants. Ces caractères peuvent avoir une application dans l'étude de la conformité génétique des vitroplants par rapport aux pieds mères. Pour citer cet article : M.

In this study, a simple and efficient plant regeneration system in Egyptian sweetpotato Abees recalcitrant cultivar via indirect organogenesis was established. Two initiation medium and different regeneration medium were tested. Hormone... more

In this study, a simple and efficient plant regeneration system in Egyptian sweetpotato Abees recalcitrant cultivar via indirect organogenesis was established. Two initiation medium and different regeneration medium were tested. Hormone free initiation medium (HFIM) treatment was found to be critical for induction of regenerative callus. Likewise, callus diagnostic structural histology confirmed de novo differentiation of meristematic domes in induced callus tissues and their further development into bud primordia. Shoot regeneration was dramatically improved by subculture of the initiated callus from HFIM onto different enriched cytokinin regeneration medium. Although, an overall analysis of variation also revealed a significant response for media used for shoot regeneration. The highest significant number of regenerated shoots per shooted callus (2.33) and frequency of regenerated shoots (80.90%) were obtained on benzyl adenine containing medium (BARM). Subsequently, regenerated shoots were rooted on hormone free medium (RM). Regenerated plants were acclimatized in controlled environment growth chamber and successfully established in the greenhouse. Hence, we report a reliable regeneration system for local recalcitrant cultivar Abees which could be used to exert selection pressure to abiotic stress or to transfer genes of agronomic interest and produce transgenic plants.

Overexpression of the proline biosynthetic gene P5CS1 results in early flowering in Arabidopsis. However, the p5cs1 loss-of-function mutant exhibits a modest delay in flowering, suggesting that P5CS2, a duplicated P5CS1 gene present in... more

Overexpression of the proline biosynthetic gene P5CS1 results in early flowering in Arabidopsis. However, the p5cs1 loss-of-function mutant exhibits a modest delay in flowering, suggesting that P5CS2, a duplicated P5CS1 gene present in the Arabidopsis, may also play a role in flower transition. In situ mRNA hybridizations and quantitative reverse transcription-polymerase chain reaction (RT-PCR) revealed that P5CS1 and P5CS2 are expressed at similar levels and with the same pattern of expression in vegetative and floral shoot apical meristems as well as in axillary meristems. Arabidopsis lines homozygous for the p5cs1 mutant and simultaneously heterozygous for the p5cs2 mutation showed a stronger late-flowering phenotype than p5cs1 single mutants, confirming that also P5CS2 plays a role in flower transition and supporting the notion of overlapping functions of the two P5CS genes in this developmental process. P5CS1 and P5CS2 have identical messenger RNA (mRNA) distributions also in embryos, but only p5cs2 mutant embryos exhibit alterations of the cellular division planes and consequently stop developing. This suggests a specific role of P5CS2 in embryogenesis and an involvement of proline in cell division. Accordingly, exogenous proline accelerated organ growth and meristem formation, and stimulated expression of the cell cycle-related protein CYCB1;1.

Vitamins are necessary compounds synthesized and utilized in plants. In tissue culture media, vitamin addition is not always common; since the amount needed by plants is relatively unknown and varies. Vitamins, in combination with other... more

Vitamins are necessary compounds synthesized and utilized in plants. In tissue culture media, vitamin addition is not always common; since the amount needed by plants is relatively unknown and varies. Vitamins, in combination with other media constituents, have been shown to have direct and indirect effects on callus growth, somatic growth, rooting, and embryonic development. For example, different studies have shown that thiamine is associated with cytokinin and has a role in inducing callus growth and rooting. Moreover, thiamine was essential in facilitating the production of more secondary metabolites such as proteases in pineapple. Both biotin and riboflavin play a role in callus development as well. Specifically, riboflavin exerts different effects on plant rooting either positively and negatively. Vitamin D known to cause uptake of calcium in animal tissue, exerts a similar effect in plants. In addition, vitamin D causes cell elongation and meristematic cell division. Vitamin C, known for its anti-oxidative properties, has also enhanced shoot growth and rooting.

Plant tissue culture, or the aseptic culture of cells, tissues, organs, and their components under defined physical and chemical conditions in vitro, is an important tool in both basic and applied studies as well as in commercial... more

Plant tissue culture, or the aseptic culture of cells, tissues, organs, and their components under defined physical and chemical conditions in vitro, is an important tool in both basic and applied studies as well as in commercial application. It owes its origin to the ideas of the German scientist, Haberlandt, at the beginning of the 20th century. The early studies led to root cultures, embryo cultures, and the first true callus/tissue cultures. The period between the 1940s and the 1960s was marked by the development of new techniques and the improvement of those already in use. It was the availability of these techniques that led to the application of tissue culture to five broad areas, namely, cell behavior (including cytology, nutrition, metabolism, morphogenesis, embryogenesis, and pathology), plant modification and improvement, pathogen-free plants and germplasm storage, clonal propagation, and product (mainly secondary metabolite) formation, starting in the mid-1960s. The 1990...

The literature describing the formation of the incisive canal is very bizarre. The fusion of the primary and secondary palatal processes leads to formation of a triangular seam, which erroneously has been taken for the future incisive... more

The literature describing the formation of the incisive canal is very bizarre. The fusion of the primary and secondary palatal processes leads to formation of a triangular seam, which erroneously has been taken for the future incisive canal. If so, the nasopalatine (incisive) nerve and its accompanying vessels were to run through the primary oronasal cavity, which is not compatible with our biological experience. This study was undertaken to shed light on this region of fusion. We focus on the formation of the incisive canal; the neighboring nasopalatine ducts, which are a transient formation, are mentioned where present. A series of seven horizontal cross-sections of human embryos and fetuses from the 7th to the 24th week of pregnancy (between 25 and 225 mm CRL, crownrump-length) were examined histologically and partly reconstructed in 3D applying the software analySIS (Soft Imaging Systems, Münster, Germany). The incisive canal did not develop at the junction of the primary and the secondary palate, but within the primary palate rostral to that location. The nasopalatine nerve and the nasopalatine artery are structures that exist before ossification starts in the area of the future incisive canal. The neighboring nasopalatine ducts were found in regions laterally and anterolaterally of the nasopalatine nerve, and it was mostly separated from it by bone. In advanced stages of development, the nasopalatine duct only existed as single epithelial remnants and was prone to obliteration.

Date Palm (Phoenix dactylifera L.) is a salt and drought tolerant fruit crop mainly cultivated in Arabian countries. Shoot tip explants of offshoots were used traditionally for various micropropagation protocols on research or commercial... more

Date Palm (Phoenix dactylifera L.) is a salt and drought tolerant fruit crop mainly cultivated in Arabian countries. Shoot
tip explants of offshoots were used traditionally for various micropropagation protocols on research or commercial levels.
However, its main disadvantage was the scarification of the entire plant. Subsequently, this hinders the micropropagation
of male and female recalcitrant individuals with no offshoots or the interesting cultivars with a limited population.
Consequently, current study is investigating the factors affecting commercial production of tissue cultured palms with
cost-effectively and short-production cycle, which may also strongly enhance the transformation protocols. The innovative
way by which the 15 cm long immature inflorescence was excised before emergence between fronds is reported herewith
this study for the first time. Established spikelet explants were able within 2-3 months only without any callus phase
to produce shining globular structures instead of immature florets. These embryogenic structures couldn’t develop
further without maturation process for 1-2 months under full darkness as well. Subsequently, well-matured embryogenic
structures were shifted to the subsequent differentiation medium under illumination conditions. After then, green shoots
and multiple somatic embryos have been subjected to the multiplication stage, then rooting and eventually successfully
transplanted in the greenhouse. All used nutrient media and their sequential usage is reported in this study by which
it became possible from one inflorescence to produce 10000 plantlets in rooting stage right now of Gulistan Pakistani
cultivar without any bad consequences on the mother tree.

Puji hanya kepada Allah SWT yang telah memberi petunjuk dan hidayah-Nya sehingga penulis dapat menyelesaikan makalah yang berjudulkan "Sistem Integumen". Adapun tujuan dari penulisan dari makalah ini adalah untuk memenuhi tugas mata... more

Puji hanya kepada Allah SWT yang telah memberi petunjuk dan hidayah-Nya sehingga penulis dapat menyelesaikan makalah yang berjudulkan "Sistem Integumen". Adapun tujuan dari penulisan dari makalah ini adalah untuk memenuhi tugas mata kuliah Struktur dan Perkembangan Hewan. Selain itu, makalah ini juga bertujuan untuk menambah wawasan tentang seluk beluk sistem integumen bagi para pembaca dan juga bagi penulis.

calmante, antiinflamatoare, analgezice, antibiotice, cicatrizante şi tonice. La seria de însuşiri care asigură succesul fructelor de căpşun s-a adăugat conţinutul ridicat în acid elagic (Maas şi Galletta, 1991; Maas şi colab., 1991),... more

calmante, antiinflamatoare, analgezice, antibiotice, cicatrizante şi tonice. La seria de însuşiri care asigură succesul fructelor de căpşun s-a adăugat conţinutul ridicat în acid elagic (Maas şi Galletta, 1991; Maas şi colab., 1991), compus cu activitate antimutagenică şi anticarcinogenică recunoscută.

During the last several years, different approaches have been made for in vitro propagation of medicinally important genus Ceropegia. The large-scale production of Ceropegias requires efficient in vitro propagation techniques to avoid the... more

During the last several years, different approaches have been made for in vitro propagation of medicinally important genus Ceropegia. The large-scale production of Ceropegias requires efficient in vitro propagation techniques to avoid the overexploitation of natural populations. Successful propagation of Ceropegia via pre-existing meristems (using apical bud, axillary bud, nodal segments, leaves, cotyledons, embryos) is influenced by several internal and external factors including ex vitro and in vitro conditions. Specific requirements during stages of micro propagation (establishment, bud induction & shoot multiplication, root induction, acclimatization and field establishment) and requisites for plant regeneration through organogenesis and somatic embryogenesis, as an important step for the implementation of plant improvement programs, were revised. New challenges for refinements of protocols for high rate of shoot multiplication and development of cost effective methods have gained importance in the recent past. Further, the development of new protocols for in vitro propagation, in vitro flowering, somatic embryogenesis and plant regeneration which is considered the most important step for successful implementation. More over Ceropegia possess traditional medicinal properties and play a vital role in the ayurvedic field. On the whole, the present review gives a consolidated account of in vitro propagation, traditional uses, chemical constituents and Retrosynthesis of Cerpegin.

Sushruta is perfect in anatomy. Sushruta has described Avayav Utpatti Siddhanta in sharirsthana. Various soft organs are formed by dosha and dhatu. This unique concept of organogenesis is very important and useful in nidan and chikitsa... more

Sushruta is perfect in anatomy. Sushruta has described Avayav Utpatti Siddhanta in sharirsthana. Various soft organs are formed by dosha and dhatu. This unique concept of organogenesis is very important and useful in nidan and chikitsa aspect. For example yakruta and pleeha are made of Rakta dhatu this indicates vitiation of Rakta dhatu results in yakruta and pleeha dushti. The organs and etiological factors show anatomical, physiological and embryological co relation.

The application of bioreactor culture techniques for plant micropropagation is regarded as one of the ways to reduce production cost by scaling-up and automation. Recent experiments are restricted to a small number of species that,... more

The application of bioreactor culture techniques for plant micropropagation is regarded as one of the ways to reduce production cost by scaling-up and automation. Recent experiments are restricted to a small number of species that, however, demonstrate the feasibility of this technology. Periodic immersion liquid culture using ebb and flood system and column-type bubble bioreactors equipped with a raft support system to maintain plant tissues at the air and liquid interface were found to be suitable for micropropagation of plants via the organogenic pathway. Balloon-type bubble bioreactors proved to be fit for micropropagation via somatic embryogenesis with less shear stress on cultured cells. Several cultivars of Lilium were successfully propagated using a two-stage culture method in one bioreactor. A large number of small-scale segments were cultured for 4 wk with periodic immersion liquid culture to induce multiple bulblets from each segment, then the bulblet induction medium was changed into bulblet growth medium by employing a submerged liquid bioreactor system. This culture method resulted in a nearly 10-fold increase in bulblet growth compared to conventional culture with solid medium. About 20 000 cuttings of virus-free potato could be obtained from 120 singlenode explants in a 20-liter balloon-type bubble bioreactor after 8 wk of culture. The percentage of ex vitro survival and root induction of the cuttings was more than 95%. Other successful results were obtained from the micropropagation and transplant production of chrysanthemum, sweetpotato, Chinese foxglove. Propagation systems via somatic embryogenesis in Acanthopanax koreanum and thornless Aralia elata were established using a liquid suspension of embryogenic determined cells. More than 500 000 somatic embryos in different stages were harvested from a 10-liter balloon-type bubble bioreactor after a 6-wk culture. Further development of these embryos in solid medium and eventually in the field was successful. The bioreactor system could reduce initial and operational cost for micropropagation, but further development of sophisticated technology might be needed to apply this system to plant micropropagation industries.

RefDoc Bienvenue - Welcome. Refdoc est un service / is powered by. ...

An efficient protocol of shoot organogenesis and plant regeneration from internode derived callus has been developed for Capsicum annuum. Optimal callus was developed from internodal segments on Murashige and Skoog (MS) medium... more

An efficient protocol of shoot organogenesis and plant regeneration from internode derived callus has been developed for Capsicum annuum. Optimal callus was developed from internodal segments on Murashige and Skoog (MS) medium supplemented with 10 μM 2,4-dichlorophenoxy acetic acid (2,4-D) and 2.0 μM 6-benzyladenine (BA). Shoot differentiation was achieved from the surface of callus when transferred on shoot induction medium containing BA and thidiazuron (TDZ) alone or in combination. The highest number of de novo adventitious shoots (25.4 ± 1.42) and shoot length (4.6 ± 0.37 cm) was recorded on MS medium supplemented with 5.0 μM BA and 2.5 μM TDZ. The individual elongated shoots were rooted well on MS medium supplemented with 1.0 μM Indole-3-butyric acid (IBA). The in vitro raised plantlets with properly developed shoot and roots were acclimatized successfully and grew well in the greenhouse. All the regenerated plants appeared normal with respect to morphology and growth characteristics with 85% survival rate.

Suman Kumari and Narender Singh (2012) In vitro plantlet regeneration from cotyledonary node explants of Salvadora persica L. a medicinally important desert tree. Journal of Agricultural Technology 8(5): 1839-1854.

Rumex tianschanicus x Rumex patientia is a prospective plant as a source of renewable energy and is also an important medicinal plant. In the present experiments an efficient and reproducible method for plant regeneration through the... more

Rumex tianschanicus x Rumex patientia is a prospective plant as a source of renewable energy and is also an important medicinal plant. In the present experiments an efficient and reproducible method for plant regeneration through the direct induction of shoot buds from hypocotyls was developed. The highest frequency of organogenetic response of explants was obtained on 7-and 12-day-old hypocotyls that had been cultured on the regeneration medium MS + 0.17 mg/l IAA + 2.2 mg/l BAP + 2% sucrose (44.06% and 48.88%, respectively). Successfully rooted plantlets were acclimated to in vivo conditions with more than a 90% survival rate. Histological analysis revealed direct organogenesis. Shoot buds arose from stele tissues and also from regenerated leaves (secondary organogenesis). Histological and SEM analyses showed a membranous-fibrillar structure, which was similar to the extracellular matrix (ECM), around nonmorphogenic callus cells. The nuclear DNA content in leaves of plantlets regenerated in vitro, estimated using flow cytometry, was similar to donor plants (about 4.6 pg/2C). This is the first report concerning the micropropagation protocol for hybrid sorrel and the first DNA 2C-value estimation for this species.

Recent advances in the development of protocols for in vitro culture and genetic manipulation have provided new avenues for the development of novel varieties of Pelargonium and for use as model systems for investigating the factors... more

Recent advances in the development of protocols for in vitro culture and genetic manipulation have provided new avenues for the development of novel varieties of Pelargonium and for use as model systems for investigating the factors controlling plant morphogenesis. Optimized techniques of meristem culture have supplemented the culture indexing methods in commercial greenhouse production resulting in availability of large-scale pathogen

A developmental constraint is a mechanism that limits the possibility of a phenotype to evolve. There is growing evidence for the existence of developmental constraints in the biological literature. We hypothesize that a developmental... more

A developmental constraint is a mechanism that limits the possibility of a phenotype to evolve. There is growing evidence for the existence of developmental constraints in the biological literature. We hypothesize that a developmental constraint prevents the savant syndrome, despite its positive aspects, from spreading in the population. Here, the developmental constraint is the result of the high interactivity among body parts in an early stage in embryological development, namely early organogenesis or the phylotypic stage. The interactivity during this stage involves all components of the embryo, and as a result mutations that affect one part of the embryo also affect other parts. We hypothesize that a mutation, which gives rise to the development of the positive aspects of the savant syndrome (e.g., an impressive memory capacity), will virtually always have a deleterious effect on the development of other phenotypic traits (e.g., resulting in autism and/or impaired motor coordination). Thus, our hypothesis states that the savant syndrome cannot spread in the population because of this developmental constraint. The finding that children with savant syndrome often have autism and physical anomalies, which are known to be established during early organogenesis, supports our hypothesis.

Callus was initiated from in vitro grown immature leaf and ex vitro grown mature leaf and rhizome explants of Agave sisalana Perr. ex. Engelm, on MS medium containing 2,4-D (9.05 μM) and kinetin (4.6 μM) or 2,4-D (9.05 μM), kinetin (4.6... more

Callus was initiated from in vitro grown immature leaf and ex vitro grown mature leaf and rhizome explants of Agave sisalana Perr. ex. Engelm, on MS medium containing 2,4-D (9.05 μM) and kinetin (4.6 μM) or 2,4-D (9.05 μM), kinetin (4.6 μM) and CH (1000 mg l−1) or mod. MS (NH4NO3, 1500 mg l−1) containing 2,4-D (9.05 μM) and kinetin (4.6 μM). Light was essential for callus formation which, however, was different in three types of explants on three different media compositions. Increasing NH4+had a negative impact while addition of CH had a positive impact on callus formation. Shoot regeneration from callus from CH-supplemented medium only was achieved for rhizome and immature leaf tissues. The highest rate of regeneration was obtained with BA (26.6 μM) as the sole hormone. Shoot buds g−1 callus varied according to BA concentrations. Shoot proliferation rate increased on half-strength MS medium containing BA (8.9 μM). Microshoots developed on MS medium containing BA (2.22 μM) and GA3 (1.44 μM) and finally rooted on MS medium containing IAA (11.42 μM). Acclimatized rooted plantlets are growing satisfactorily in ex vitro. This is the first report on plant regeneration via organogenesis of A. sisalana.

In Romania, the studies on raspberry micropropagation have been under way since the 80`s. Replacing conventional propagation methods and producing virus-free planting material have been the objectives of the research. Aimed at developing... more

In Romania, the studies on raspberry micropropagation have been under way since the 80`s. Replacing conventional propagation methods and producing virus-free planting material have been the objectives of the research. Aimed at developing an efficient micropropagation regime and improving the methodology of culturing various aspects of raspberry tissue culture have been systematically studied in recent years.

An effective system for in vitro regeneration of adventitious shoots from callus for the transformation or mutation of gerbera was developed. Callus was produced from petioles of the youngest 3-4 leaves detached from auxillary shoots... more

An effective system for in vitro regeneration of adventitious shoots from callus for the transformation or mutation of gerbera was developed. Callus was produced from petioles of the youngest 3-4 leaves detached from auxillary shoots produced in vitro. Induction medium, on which leaves were incubated over 3 or 6 days, contained 2.3 µM thidiazuron and 0.53 µM α-naphthaleneacetic acid. Explants were than transferred to one of three regeneration media with lower levels of growth regulators. Regeneration was quantified over four (4-weeks each) passages at the time of explant transfer to fresh medium. Direct shoot regeneration occurred during the first 4 weeks, and after these shoots were discarded a semi-compact organogenic callus was produced. Effectiveness of shoot regeneration depended on four criteria: the cultivar (three cultivars were tested), the sequence of passage on regeneration medium, the growth regulators in regeneration medium and the duration of the induction period. Regeneration potential from calli of all cultivars increased from the first to the fourth passage. Duration of the incubation period on induction medium (3 or 6 days) influenced regeneration to varying degrees, depending on the cultivar used and the regeneration medium contents. There were no differences between two of the regeneration media -B, containing 2.2 µM 6-benzyladenine and 0.3 µM indole-3-acetic acid and C, containing 4.4 µM 6-benzyladenine, 4.6 µM zeatin and 0.6 µM indole-3-acetic acid. Cultivar Mariola was the most productive and regenerated more than seven shoots per callus in the fourth passage. Regeneration on medium B was further evaluated on four additional gerbera cultivars.

Galectin-3 has been suspected of modulating cell to extracellular matrix interactions in a novel fashion ever since it was first described. However, the rapid accumulation of research data in just the last 8 years alone has completely... more

Galectin-3 has been suspected of modulating cell to extracellular matrix interactions in a novel fashion ever since it was first described. However, the rapid accumulation of research data in just the last 8 years alone has completely changed our perspective of this multifunctional protein. Its chimeric nature (consists of carbohydrate recognition and collagen like domains) somehow makes it suited to interact with a plethora of interesting extracellular matrix proteins some of which might enable it to cross the plasma membrane despite its lack of appropriate signal peptides. It is now becoming established as a mediator of signal transduction events on the cell surface as well as a mediator of a variety of extra-cellular processes such as kidney development, angiogenesis, neuronal functions, tumor metastasis, autoimmune disorders, endocytosis and possibly exocytosis. Nevertheless, it still retains its unique position as a mediator/modulator of cell to extracellular matrix adhesive interactions. Cells, particularly epithelial cells which lack galectin-3 expression, interact poorly with their extracellular matrices. In some of these processes, it functions as a matricellular protein, displaying both pro- and anti-adhesive properties. Published in 2004.

The control of dormancy in yam (Disocorea spp.) tubers is poorly understood and attempts to shorten the long dormant period (i.e. cause tubers to sprout or germinate much earlier) have been unsuccessful. The aim of this study was to... more

The control of dormancy in yam (Disocorea spp.) tubers is poorly understood and attempts to shorten the long dormant period (i.e. cause tubers to sprout or germinate much earlier) have been unsuccessful. The aim of this study was to identify and define the phases of dormancy in Dioscorea rotundata tubers, and to produce a framework within which dormancy can be more effectively studied.

An efficient regeneration system, direct and indirect organogenesis, was developed for Curculigo orchioides-an endangered medicinal herb. Shoot multiples were initiated from in vitro grown leaf explants through direct organogenesis on... more

An efficient regeneration system, direct and indirect organogenesis, was developed for Curculigo orchioides-an endangered medicinal herb. Shoot multiples were initiated from in vitro grown leaf explants through direct organogenesis on Murashige and Skoog's (MS) medium containing ½ strength nitrogen salts and 0.44 µM BA. Almost 10 shoots were obtained per leaf explant (1 cm long). On the other hand MS medium with full strength nitrogen salts and 2.22 µM BA, stimulated callus formation and almost 8 shoots were obtained per leaf explant (1 cm long ). Comparative study of shoots regenerated directly or through callus revealed differences in number of leaves, shoot length, root length, fresh and dry weight.

Epigenetic mechanisms are highly dynamic events that modulate gene expression. As more accurate and powerful tools for epigenetic analysis become available for application in a broader range of plant species, analysis of the epigenetic... more

Epigenetic mechanisms are highly dynamic events that modulate gene expression. As more accurate and powerful tools for epigenetic analysis become available for application in a broader range of plant species, analysis of the epigenetic landscape of plant cell cultures may turn out to be crucial for understanding variant phenotypes. In vitro plant cell and tissue culture methodologies are important for many ongoing plant propagation and breeding programmes as well as for cutting-edge research in several plant model species. Although it has long been known that in vitro conditions induce variation at several levels, most studies using such conditions rely on the assumption that in vitro cultured plant cells/tissues mostly conform genotypically and phenotypically. However, when largescale clonal propagation is the aim, there has been a concern in confirming true-to-typeness using molecular markers for evaluating stability. While in most reports genetic variation has been found to occur at relatively modest frequencies, variation in DNA methylation patterns seems to be much more frequent and in some cases it has been directly implicated in phenotypic variation. Recent advances in the field of epigenetics have uncovered highly dynamic mechanisms of chromatin remodelling occurring during cell dedifferentiation and differentiation processes on which in vitro adventitious plant regeneration systems are based. Here, an overview of recent findings related to developmental switches occurring during in vitro culture is presented. Additionally, an update on the detection of epigenetic variation in plant cell cultures will be provided and discussed in the light of recent progress in the plant epigenetics field.

The large size and rapid development of amphibian embryos has facilitated ground-breaking discoveries in developmental biology. Here, we describe the embryogenesis of the Budgett's frog (Lepidobatrachus laevis), an unusual species with... more

The large size and rapid development of amphibian embryos has facilitated ground-breaking discoveries in developmental biology. Here, we describe the embryogenesis of the Budgett's frog (Lepidobatrachus laevis), an unusual species with eggs that are over twice the diameter of laboratory Xenopus, and embryos that can tolerate higher temperatures to develop into a tadpole four times more rapidly. In addition to detailing their early development, we demonstrate that, like Xenopus, these embryos are amenable to explant culture assays and can express exogenous transcripts in a tissue-specific manner. Moreover, the steep developmental trajectory and large scale of Lepidobatrachus make it exceptionally well-suited for morphogenesis research. For example, the developing organs of the Budgett's frog are massive compared to those of most model species, and are composed of larger individual cells, thereby affording increased subcellular resolution of early vertebrate organogenesis. Furthermore, we found that complete limb regeneration, which typically requires months to achieve in most vertebrate models, occurs in a matter of days in the Budgett's tadpole, which substantially accelerates the pace of experimentation. Thus, the unusual combination of the greater size and speed of the Budgett's frog model provides inimitable advantages for developmental studies-and a novel inroad to address the mechanisms of spatiotemporal scaling during evolution.

Impressive progress has been made since the turn of the century in the field of stem cells. Different types of stem cells have now been isolated from different types of tissues. Pluripotent stem cells are the most promising cell source... more

Impressive progress has been made since the turn of the century in the field of stem cells. Different types of stem cells have now been isolated from different types of tissues. Pluripotent stem cells are the most promising cell source for organ regeneration. One such cell type is the germline cell-derived pluripotent cell, which is derived from adult spermatogonial stem cells. The germline cell-derived pluripotent stem cells have been obtained from both human and mouse and, importantly, are adult stem cells with embryonic stem cell-like properties that do not require specific manipulations for pluripotency acquisition, hence bypassing problems related to induced pluripotent stem cells and embryonic stem cells. The germline cell-derived pluripotent stem cells have been induced to differentiate into cells deriving from the three germ layers and shown to be functional in vitro. This review will discuss the plasticity of the germline cell-derived pluripotent stem cells and their potent...

| The limb bud is of paradigmatic value to understanding vertebrate organogenesis. Recent genetic analysis in mice has revealed the existence of a largely self-regulatory limb bud signalling system that involves many of the pathways that... more

| The limb bud is of paradigmatic value to understanding vertebrate organogenesis. Recent genetic analysis in mice has revealed the existence of a largely self-regulatory limb bud signalling system that involves many of the pathways that are known to regulate morphogenesis. These findings contrast with the prevailing view that the main limb bud axes develop largely independently of one another. In this Review, we discuss models of limb development and attempt to integrate the current knowledge of the signalling interactions that govern limb skeletal development into a systems model. The resulting integrative model provides insights into how the specification and proliferative expansion of the anteroposterior and proximodistal limb bud axes are coordinately controlled in time and space.

In vitro regeneration of buds and shoots via organogenesis in two genotypes of Sansevieria trifasciata was established. Leaf segments (1cm x 1cm) of cv. Hahnii and cv. Lorentii were cultured on Murashige and Skoog (MS) basal medium... more

In vitro regeneration of buds and shoots via organogenesis in two genotypes of Sansevieria trifasciata was established. Leaf segments (1cm x 1cm) of cv. Hahnii and cv. Lorentii were cultured on Murashige and Skoog (MS) basal medium containing 2.4-dichloro-phenoxyacetic acid (2.4-D) for 1 week, trans-ferred into MS medium without plant growth regulator (MS0) for 1 week, and then cultured to MS medium containing different concentrations of benzyladenine (BA:0; 0.1; 0.25; 0.5; 1 and 2 mg/l) for 3 consecutive passages with 4 week intervals. The results showed that BA proved to be an effective cytokinin to induce the formation of adventitious buds and shoots in two cultivars of Sansevieria trifasciata. The maximum of 12 propagules per explant of Lorentii and 9.3 propagules of Hahnii were obtained in medium with 2 mg/l BA after 14 weeks. Furthermore, regenerative capacity to form shoot buds and propagules was genotype dependent. The popagules number formed by cv. Lorentii was significantly higher than those formed by cv. Hahnii. The average shoot length formed by cv. Lorentii was also higher than those of cv. Hahnii. Shoots of both cultivars were successfully ex vitro rooted and acclimatized to the greenhouse with high survival rate (95.9 -100%).