Senthilkumar Palanisamy - Academia.edu (original) (raw)

Papers by Senthilkumar Palanisamy

Genes

Sida cordifolia is a medicinal shrub that is conventionally used in the Indian system of medicine... more Sida cordifolia is a medicinal shrub that is conventionally used in the Indian system of medicine;however, the genes contributing to its medicinal properties have been minimally explored, thus limiting its application. High-throughputsequencing and Liquid Chromatography with tandem mass spectrometry(LC-MS/MS) technologies were applied to unravel the medicinally important bioactive compounds. As a result, transcriptomic sequencing generated more than 12 GB of clean data, and 187,215 transcripts were obtained by de novoassembly. These transcripts were broadly classified into 20 classes, based on the gene ontology classification, and 6551 unigenes were annotated using Kyoto Encyclopedia of Genes and Genomes (KEGG) database with more than 142 unigenes involved in the biosynthesis of secondary metabolites. LC-MS/MS analysis of three tissues of Sida cordifolia revealed that acacetin and procyanidin are some important metabolites identified thatcontribute to its medicinal value. Several ke...

Asphondylia singanallurensis Vasanthakumar & Sharma, sp. nov. ( Figs ... more Asphondylia singanallurensis Vasanthakumar & Sharma, sp. nov. ( Figs 1–22) The diagnostic characters of the genus, Asphondylia are discussed in detail by Gagné et al. (2018). Type material. Holotype ♂ (Ent 10/205), Singanallur Lake, Coimbatore, Tamil Nadu, India ( 10.9877°N; 77.0238°E),collected as gall by DV on 26.ix.2017; Paratype: 4 ♂ (Ent 10/206), collected as gall on 22.ix.2018, 3♀ (Ent 10/207), 6 larvae, collected as gall on 23.ix.2018), 6 pupae (Collected as gall on 22.ix.2018 and 12.vii.2019); 7 pupal exuviae same data as holotype.

Candida albicans is a commensal human fungal pathogen that colonizes and develops dental biofilm ... more Candida albicans is a commensal human fungal pathogen that colonizes and develops dental biofilm which cause Oral candidiosis. This study investigates the effects of a new molecule Thidiazuron against the growth and biofilm formation properties of C. albicans. This study applied computational and in vitro approaches such as broth microdilution, SEM, time-kill dynamics, crystal violet assay, XTT reduction assay, ergosterol quantification and quantitative RT PCR analysis of gene expression to validate the growth and biofilm inhibitory potential of thidiazuron against C. albicans. Preliminary molecular docking study revealed potential interaction between thidiazuron and amino acids residues of CYP51. Further in vitro anti-fungal susceptibility test, SEM and time kill analysis revealed anti-fungal potency of thidiazuron in dose and time dependent passion. Crystal violet staining, XTT reduction assay and Acridine Orange staining visually confirmed biofilm inhibitory potential of thidiazu...

Journal of Threatened Taxa, 2020

The present study reports a leaf gall midge, Procontarinia robusta Li, Bu & Zhang of Mango, Mangi... more The present study reports a leaf gall midge, Procontarinia robusta Li, Bu & Zhang of Mango, Mangifera indica L. from India. It is being reported for the first time from India. Earlier, this species was reported from China, Indonesia and East Timor. A brief diagnosis of its immature stages and coloured images are given to facilitate easy identification.

Plant Physiology Reports, 2021

Aquaporins (AQPs) are the membrane water channel proteins present in all organisms. Plants have t... more Aquaporins (AQPs) are the membrane water channel proteins present in all organisms. Plants have the highest amount and the largest variety of aquaporin homologs with diverse subcellular localization patterns, solute specificity, and gating properties. As aquaporins regulate plant water relations, they are alleged to play a pivotal role in the defense response of plants against biotic and abiotic stress. In particular, aquaporins play a crucial role in defense response against drought stress. Plants in arid and semi-arid regions which are severely affected by drought, overcome this by absorbing water from external sources besides precipitation such as fog, dew and cloud mist through leaves by a process known as foliar water uptake. Studies had shown aquaporin's role in foliar water uptake, which regulates the transpiration rate and hydraulic conductivity in plants. However, the molecular mechanisms behind it are still up in the air. The current review emphasizes on the aquaporins...

Zootaxa

Jujube Ziziphus jujuba Mill. (Rhamnaceae), known as “Ber” in India, is an evergreen thorny shrub ... more Jujube Ziziphus jujuba Mill. (Rhamnaceae), known as “Ber” in India, is an evergreen thorny shrub with reddish-brown fruits, chiefly found in Southeast Asia (Reza 2014). Up to now three species of gall midges have been associated with jujube: Phyllodiplosis jujubae Grover & Bakshi, and Silvestrina jujubae Chandra in India and Dasineura jujubifolia Jiao & Bu in China (Grover & Bakhshi 1978; Chandra 1988; Jiao et al. 2017). Between 2015 and 2018 during field trips by DV & VRP to Singanallur lake area, Coimbatore, Tamil Nadu, one of us (DV) noticed and collected leaves of Z. jujuba containing small galls on the midrib region of leaves. In the laboratory the leaves were dissected, and causative agent identified as a gall midge. The adults were reared and identified as undescribed species of gall midge, here described and named Asphondylia singanallurensis Vasanthakumar & Sharma. Type specimens were processed and mounted in Canada balsam as per the method in Kolesik et al. (2015). Holotyp...

Metallothionein (MT) has been used widely as a potential molecular marker to detect the deleterio... more Metallothionein (MT) has been used widely as a potential molecular marker to detect the deleterious effects of heavy metals in aquatic ecosystem. Here we exposed ayu, Plecoglossus altivelis, to zinc (Zn) and tested the distribution as well as the induction of MT in various tissues such as liver, kidney, intestine and stomach. MT induction was significant in liver tissue, followed by kidney and intestine, whereas no induction was detected in stomach. The gene encoding ayu MT was successfully cloned and characterized. Complete nucleotide sequencing and analysis of the 4.5 kb DNA fragment containing the ayu MT gene revealed that the gene has three exons interrupted by two introns, a 5-flanking region of about 2.5 kb and about 1.6 kb of 3-flanking region. In grouper heart and kidney cells, the 2.5 kb promoter containing eight metal responsive elements (MREs), two hepatic nuclear factor 5 responsive elements (HNF5REs) and one cAMP responsive element (CRE) had the highest reporter activity.

The purpose of the study is to reveal the changes in the activity of different antioxidative enzy... more The purpose of the study is to reveal the changes in the activity of different antioxidative enzymes in banjhi and active buds. Reactive oxygen species, such as hydrogen peroxide, superoxide and hydroxyl radicals, are by-products of biological redoxreactions. Plant produces antioxidant enzymes, such as catalase, superoxide dismutase, ascorbate peroxidase, glutathione reductase and peroxidase to scavenge these reactive oxygen species. In the present study activity of polyphenol oxidase and antioxidative enzymes such as catalase, ascorbate peroxidase, superoxide dismutase, glutathione reductase and peroxidase were analyzed to find their variation in dormant (banjhi) and active buds in five clones of tea (Camellia sinensis) grown in the field. The activity of all antioxidative enzymes was higher in dormant bud than the actively growing bud in all the clones. But the activity of polyphenol oxidase was found to be reversal of the antioxidative enzymes. While considering the difference in...

Computational approach was used in to identify potent macrophage specific miRNAs involved in basi... more Computational approach was used in to identify potent macrophage specific miRNAs involved in basic biological process of Salmo salar. Analysis of 1119 ESTs from macrophages of Atlantic salmon (Salmo salar) infected with Aeromonas salmonicida revealed expression of 3 miRNAs. Phylogenetic analysis of both the pre-miRNA sequence revealed its evolutionarily conserved nature among various species. Identified targets of the predicted miRNAs revealed the role of miRNA in pathogenesis, stress response and allosteric exchange of histones. Further detailed studies of these miRNAs will help in revealing its function in different biological process necessary for the action of macrophages upon pathogen infection.

Journal of Crop Improvement, 2014

ABSTRACT Tea mosquito (Helopeltis theivora) is a serious pest in tea (Camellia sinensis) growing ... more ABSTRACT Tea mosquito (Helopeltis theivora) is a serious pest in tea (Camellia sinensis) growing regions, causing severe crop loss. Identification of markers associated with tea-mosquito resistance is necessary to develop cultivars tolerant to tea mosquito from the available germplasm. This study was conducted to identify random amplified polymorphic DNA (RAPD) markers associated with tolerance against tea mosquito. The RAPD markers were then sequenced and converted into sequence-characterized amplified region (SCAR) markers. A total of 138 decamer primers were used to screen genomic DNA from four susceptible and four relatively tolerant tea cultivars. Only three RAPD markers (OPW-03725, OPT-01625, and OPG-11750) were linked to tea-mosquito resistance. These markers were converted into co-dominant SCAR markers, Rht1, Rht2, and Rht3. This is the first study reporting the development of markers for tea-mosquito resistance. These markers can be used as an important tool to screen tea cultivars for tea-mosquito resistance/susceptibility.

Plant Physiology and Biochemistry, 2011

Growth regulation associated with dormancy is an essential element in plant's life cycle that lea... more Growth regulation associated with dormancy is an essential element in plant's life cycle that leads to changes in expression of large number of genes. Forward and reverse suppression subtractive hybridization (SSH) libraries were developed to identify and characterize the genes associated with bud (banjhi) dormancy in tea (Camellia sinensis (L.) O. Kuntze). Efficiency of subtraction was confirmed by comparing the abundance of b-actin gene. A total of 17 and 45 unique sequences were obtained from forward and reverse SSH library respectively. Many of the differentially regulated genes have unknown (41.1% and 26.7%) or hypothetical functions (11.7% and 2.2%) in forward and reverse SSH library respectively, while others have a role in cell growth and metabolism. Further, semi-quantitative RT-PCR was carried out for selected genes to validate the quality of ESTs from SSH library. Gene Ontology analysis identified a greater association of these ESTs in cellular metabolic pathways and their relevance to bud dormancy. Based on the EST data, the putative role of identified genes from tea is discussed in relation to dormancy, which includes various metabolic and signalling pathways. We demonstrated that SSH is an efficient tool for enriching up-and down-regulated genes related to bud dormancy in tea. This study represents an attempt to investigate banjhi dormancy in tea under field conditions, and the findings indicate that there is a potential to develop new approaches to modulate dormancy in this species.

Applied Biochemistry and Biotechnology, 2013

Bud dormancy is of ecological and economical interest due to its impact on tea (Camellia sinensis... more Bud dormancy is of ecological and economical interest due to its impact on tea (Camellia sinensis (L.) O. Kuntze) plant growth and yield. Growth regulation associated with dormancy is an essential element in plant&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s life cycle that leads to changes in expression of large number of genes. In order to identify and provide a picture of the transcriptome profile, cDNA library was constructed from dormant bud (banjhi) of tea. Sequence and gene ontology analysis of 3,500 clones, in many cases, enabled their functional categorization concerning the bud growth. Based on the cDNA library data, the putative role of identified genes from tea is discussed in relation to growth and dormancy, which includes morphogenesis, cellular differentiation, tropism, cell cycle, signaling, and various metabolic pathways. There was a higher representation of unknown processes such as unknown molecular functions (65.80 %), unknown biological processes (62.46 %), and unknown cellular components (67.42 %). However, these unknown transcripts represented a novel component of transcripts in tea plant bud growth and/or dormancy development. The identified transcripts and expressed sequence tags provides a valuable public resource and preliminary insights into the molecular mechanisms of bud dormancy regulation. Further, the findings will be the target of future expression experiments, particularly for further identification of dormancy-related genes in this species.

Applied Biochemistry and Biotechnology, 2012

Tea (Camellia sinensis (L.) O. Kuntze) is an economically important plant cultivated for its leav... more Tea (Camellia sinensis (L.) O. Kuntze) is an economically important plant cultivated for its leaves. Infection of Pestalotiopsis theae in leaves causes gray blight disease and enormous loss to the tea industry. We used suppressive subtractive hybridization (SSH) technique to unravel the differential gene expression pattern during gray blight disease development in tea. Complementary DNA from P. theae-infected and uninfected leaves of disease tolerant cultivar UPASI-10 was used as tester and driver populations respectively. Subtraction efficiency was confirmed by comparing abundance of β-actin gene. A total of 377 and 720 clones with insert size &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;250 bp from forward and reverse library respectively were sequenced and analyzed. Basic Local Alignment Search Tool analysis revealed 17 sequences in forward SSH library have high degree of similarity with disease and hypersensitive response related genes and 20 sequences with hypothetical proteins while in reverse SSH library, 23 sequences have high degree of similarity with disease and stress response-related genes and 15 sequences with hypothetical proteins. Functional analysis indicated unknown (61 and 59 %) or hypothetical functions (23 and 18 %) for most of the differentially regulated genes in forward and reverse SSH library, respectively, while others have important role in different cellular activities. Majority of the upregulated genes are related to hypersensitive response and reactive oxygen species production. Based on these expressed sequence tag data, putative role of differentially expressed genes were discussed in relation to disease. We also demonstrated the efficiency of SSH as a tool in enriching gray blight disease related up- and downregulated genes in tea. The present study revealed that many genes related to disease resistance were suppressed during P. theae infection and enhancing these genes by the application of inducers may impart better disease tolerance to the plants.

Protein purification from plant tissues is a crucial process for numerous applications in biology... more Protein purification from plant tissues is a crucial process for numerous applications in biology but it is a tedious and time-consuming task. Bulk amount of starting material is required to purify a small amount of particular protein. In general, the first step involves preparation of crude extract in saline or buffer solution. From the crude extract, the protein can be fractionated through selective precipitation with salts (ammonium sulphate, etc.,) at different concentrations. Consequently the development of efficient protocol is required for its selective extraction prior to purification. Our aim is to optimize a protocol for the extraction of lectin in huge amount from different plant tissues. We have used different extraction procedures, which includes different buffers at various pH, molar concentrations, incubation time and additional of enhancing components viz., CaCl2, PMSF to find the effective condition for the extraction of lectins from leaf, bulb and rhizomes of diffe...

Applied biochemistry and biotechnology, 2014

Reactive oxygen species (ROS) production is the first level of response by a host during stress. ... more Reactive oxygen species (ROS) production is the first level of response by a host during stress. Even though the ROS are toxic to cell, when present in a limited amount, they act as a signalling molecule for the expression of defence-related genes and later are scavenged by either enzymatic or non-enzymatic mechanisms of the host. The different anti-oxidative enzymes like glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APO), peroxidase (POD) and polyphenol oxidase (PPO) were estimated, and their activities were compared between infected and healthy leaves of the tolerant and susceptible cultivars of tea. The infected leaves of the susceptible cultivars registered higher amount of enzyme activity when compared with the tolerant cultivars. The study reveals that the more anti-oxidative enzymes, the more susceptible the cultivar will be.