Francisco Aragão - Academia.edu (original) (raw)

Papers by Francisco Aragão

RNA interference (RNAi) techniques are relevant in studies involving the search for improved nutr... more RNA interference (RNAi) techniques are relevant in studies involving the search for improved nutritional values in plants, and in the development of plants that are better adapted to different ecosystems, as well as optimal utilization of raw materials derived from plants for industrial use. RNAi evolved as a natural cellular defense mechanism against viruses, genomic confinement of retrotransposons, and as a cellular strategy for post-transcriptional regulation of gene expressions. A central feature in the mechanism of RNA inference is the participation of small RNA molecules. There are two types of small RNA molecules: small interfering RNAs (siRNA) and microRNA (miRNA). Several plants are resistant to viruses by virtue of an inherent double-stranded RNAs (dsRNA) and siRNA generating system whose targets are gene sequences essential for viral pathogenicity.

Proteomics

The seed-feeding beetle Callosobruchus maculatus is an important cowpea pest (Vigna unguiculata) ... more The seed-feeding beetle Callosobruchus maculatus is an important cowpea pest (Vigna unguiculata) as well as an interesting model to study insect digestive physiology. The larvae of C. maculatus rely on cysteine and aspartic peptidases to digest proteins in their diet. In this work, the global proteomic changes induced in the intestinal tract of larval C. maculatus challenged by the ingestion of cystatin, a cysteine peptidase inhibitor, was investigated by a nanoLC-MS/MS approach. The ingestion of cystatin caused a delay in the development of the larvae, but the mortality was not high, indicating that C. maculatus is able to adapt to this inhibitor. This proteomic strategy resulted in the identification of 752 and 550 protein groups in the midgut epithelia and midgut contents, respectively, and quantitative analyses allowed us to establish relative differences of the identified proteins. Ingestion of cystatin led to significant changes in the proteome of both the midgut epithelia and...

Plant Pathology, 2010

Pathogenesis of Sclerotinia sclerotiorum (white mould) has been associated with fungal secretion ... more Pathogenesis of Sclerotinia sclerotiorum (white mould) has been associated with fungal secretion of oxalic acid (OA). Enzymes capable of degrading OA have been utilized to produce transgenic resistant plants. Transgenic soybean lines containing the decarboxylase gene (oxdc) isolated from a Flammulina sp. were produced by the biolistic process. Molecular analysis revealed successful incorporation of the gene into the plant genome and showed that the oxdc gene was transferred to the progeny plants. Sixteen T 2 transgenic events were screened for S. sclerotiorum resistance using a detached leaf assay. The white mould disease progress curve displayed a significant delay in symptom development in all oxdc events compared with the nontransgenic genotype. Area under the disease progress curve (AUDPC) showed reduction in severity ranging from 61% to 96% comparing the oxdc events with the nontransgenic control. One event (OXDC.9.21) presented some plants that did not show any symptoms after 92 h. RT-PCR analysis for detection of oxdc gene transcripts suggested that expression of the oxdc gene is associated with resistance to S. sclerotiorum.

Plant Science, 1994

... evaluation of the strength of the Brazil nut 2S promoter in comparison with an analogous pro-... more ... evaluation of the strength of the Brazil nut 2S promoter in comparison with an analogous pro-moter from Arabidopsis and the 35S promoter from CaMV showed that the latter drives transientGUS-expression in ... [8] LAB De Castro, Z. Lacerda, RA Aramayo, MJ Sampaio and ES ...

Genetics and molecular research : GMR, 2007

Evaluation of transgenic crops under field conditions is a fundamental step for the production of... more Evaluation of transgenic crops under field conditions is a fundamental step for the production of genetically engineered varieties. In order to determine if there is pollen dispersal from transgenic to nontransgenic soybean plants, a field release experiment was conducted in the Cerrado region of Brazil. Nontransgenic plants were cultivated in plots surrounding Roundup Ready transgenic plants carrying the cp4 epsps gene, which confers herbicide tolerance against glyphosate herbicide, and pollen dispersal was evaluated by checking for the dominant gene. The percentage of cross-pollination was calculated as a fraction of herbicide-tolerant and -nontolerant plants. The greatest amount of transgenic pollen dispersion was observed in the first row, located at one meter from the central (transgenic) plot, with a 0.52% average frequency. The frequency of pollen dispersion decreased to 0.12% in row 2, reaching 0% when the plants were up to 10 m distance from the central plot. Under these co...

Plant molecular biology, 1997

The expression of Brazil nut storage albumin genes is highly regulated during seed development. S... more The expression of Brazil nut storage albumin genes is highly regulated during seed development. Several sequences in the promoter of one of these genes show homologies with the target sites of the maize O2 bZIP regulatory protein. We therefore asked whether the O2 protein would recognize these promoter sequences. We show that the O2 protein binds to three different sequences (F1, F2 and F3). F1 and F3 are hybrid C/G and A/G boxes, respectively, that are homologous to the O2-binding site of a maize alpha-zein gene. F2 is a new O2-binding sequence related to the O2 target sites of the Coix alpha-coxin, the maize b-32 genes and the AP-1 pseudopalindrome. Molecular modelling showed that an Asn and a Ser in the 02 DNA binding domain make different base-specific contacts with each operator. 5' Promoter deletions of the be2S1 gene showed that the domain containing the O2 target sites F1 and F2 is required for detectable reporter gene expression in transgenic tobacco seeds. Moreover, th...

Genetics and molecular research : GMR, 2005

An association of two techniques, nuclear transfer (NT), and transfection of somatic animal cells... more An association of two techniques, nuclear transfer (NT), and transfection of somatic animal cells, has numerous potential applications and considerable impact, mainly in agriculture, medicine, pharmacy, and fundamental biology. In addition, somatic cell nuclear transfer is the most efficient alternative to produce large transgenic animals. We compared in vitro and in vivo developmental capacities of NT using fibroblast cells isolated from a 14-month-old cloned Simmental heifer (FCE) vs the same line transfected with a plasmid containing neomycin-resistant genes (TFCE). There were no significant differences (P > 0.5) in either fusion (116/149 = 78% vs 216/301 = 72%), cleavage (78/116 = 67% vs 141/216 = 65%) and blastocyst (35/116 = 30% vs 52/216 = 24%) rates or in pregnancy rate at 30 to 35 days after embryo transfer (2/17 vs 3/17) between NT using FCE and TFCE, respectively. Transfection and long-term in vitro culture of transfected cells did not affect developmental capacity of ...

Methods in molecular biology (Clifton, N.J.), 2015

RNA interference (RNAi) has emerged as a leading technology in designing genetically modified cro... more RNA interference (RNAi) has emerged as a leading technology in designing genetically modified crops engineered to resist viral infection. The last decades have seen the development of a large number of crops whose inherent posttranscriptional gene silencing mechanism has been exploited to target essential viral genes through the production of dsRNA that triggers an endogenous RNA-induced silencing complex (RISC), leading to gene silencing in susceptible viruses conferring them with resistance even before the onset of infection. Selection and breeding events have allowed for establishing this highly important agronomic trait in diverse crops. With improved techniques and the availability of new data on genetic diversity among several viruses, significant progress is being made in engineering plants using RNAi with the release of a number of commercially available crops. Biosafety concerns with respect to consumption of RNAi crops, while relevant, have been addressed, given the fact t...

Genetics and molecular research : GMR, 2005

The development of an efficient transfection system in livestock cells is an important step towar... more The development of an efficient transfection system in livestock cells is an important step towards investigating gene transfer and the functioning and production of transgenic animals. Important factors involved in cationic liposome mediated gene transfer were evaluated through in vitro transfection of bovine, caprine and ovine fibroblast cells. Transfection of plasmid DNA complexes of different commercially available liposomes (Lipofectamine, Lipofectin, Cellfectin and DMRIE-C; Gibco-BRL, USA) was evaluated utilizing the following parameters: DNA/liposome ratio, cell density, DNA conformation, and the effect of transfection time on the efficiency of bovine fibroblasts to express a reporter gene. The effects and concentrations of liposomes were also evaluated in caprine and ovine fibroblasts. Lipofectamine alone and Lipofectamine with Plus reagent induced high-frequency expression of beta-galactosidase and neo genes in all cells evaluated (47 and 88.3%, respectively). Regarding phe...

Plos One, 2012

Starting from the premise that a wealth of potentially biologically active peptides may lurk with... more Starting from the premise that a wealth of potentially biologically active peptides may lurk within proteins, we describe here a methodology to identify putative antimicrobial peptides encrypted in protein sequences. Candidate peptides were identified using a new screening procedure based on physicochemical criteria to reveal matching peptides within protein databases. Fifteen such peptides, along with a range of natural antimicrobial peptides, were examined using DSC and CD to characterize their interaction with phospholipid membranes. Principal component analysis of DSC data shows that the investigated peptides group according to their effects on the main phase transition of phospholipid vesicles, and that these effects correlate both to antimicrobial activity and to the changes in peptide secondary structure. Consequently, we have been able to identify novel antimicrobial peptides from larger proteins not hitherto associated with such activity, mimicking endogenous and/or exogenous microorganism enzymatic processing of parent proteins to smaller bioactive molecules. A biotechnological application for this methodology is explored. Soybean (Glycine max) plants, transformed to include a putative antimicrobial protein fragment encoded in its own genome were tested for tolerance against Phakopsora pachyrhizi, the causative agent of the Asian soybean rust. This procedure may represent an inventive alternative to the transgenic technology, since the genetic material to be used belongs to the host organism and not to exogenous sources.

Revista da Sociedade Brasileira de Medicina Tropical, 1999

Resumo O objetivo do trabalho é medir as coberturas das atividades municipais de controle de Aede... more Resumo O objetivo do trabalho é medir as coberturas das atividades municipais de controle de Aedes aegypti e/ou Aedes albopictus, o casa-casa eo arrastão, realizadas entre 1989 e 1995 na região de São José do Rio Preto, São Paulo e avaliar a correlação cruzada entre elas ...

Plant Science, 2006

The rep gene of Bean golden mosaic virus (BGMV) is essential for virus replication. A mutated rep... more The rep gene of Bean golden mosaic virus (BGMV) is essential for virus replication. A mutated rep gene with amino acid codon change in the putative nucleoside triphosphate (NTP) binding motif D262R was created. Phaseolus vulgaris transformation was achieved with a vector that contained the mutated rep and bar genes. A total of 17 initial (T 0 ) transformants were analyzed. One line (M1/4) showed tolerance to glufosinate ammonium and partial resistance to the virus, that is, disease incidence depended on inoculation level. The incidence of BGMV increased with the increasing number of viruliferous whiteflies per plant, both in the transgenic and in the control plants. However, the number of symptomless plants was significantly higher in the transgenic group. The line M1/4 was studied during several generations and presented stability in the transgene loci and virus resistance. Southern blot analysis with genomic DNA of eight generations led to an estimate of two copies of the rep gene integrated at the same locus. RT-PCR analysis revealed the presence of both bar and rep genes transcripts. The mutated REP protein was present in amounts detectable by Western blot analysis in transgenic plants. #

Common bean is grown and consumed principally in developing countries in Latin America, Africa, a... more Common bean is grown and consumed principally in developing countries in Latin America, Africa, and Asia. It is largely a subsistence crop eaten by its producers and, hence, is underestimated in production and commerce statistics. Common bean is a major source of dietary protein, which complements carbohydrate-rich sources such as rice, maize, and cassava. It is also a rich source

Fems Microbiology Letters, 2000

Metarhizium anisopliae var. acridum (syn. M. flavoviride) is recognized as a highly specific and ... more Metarhizium anisopliae var. acridum (syn. M. flavoviride) is recognized as a highly specific and virulent mycopathogen of locusts and grasshoppers and is currently being developed as a biological control agent for this group of insects in Brazil. Intact conidia of M. anisopliae var. acridum strain CG423 were transformed using microparticle bombardment. Plasmids used were: (1) pBARKS1 carrying the bar gene

GM crops & food

Genetically modified (GM) crops is considered the fastest adopted crop technology in the history ... more Genetically modified (GM) crops is considered the fastest adopted crop technology in the history of modern agriculture. However, possible undesirable and unintended effects must be considered during the research steps toward development of a commercial product. In this report we evaluated effects of a common bean virus resistant line on arthropod populations, considered as non-target organisms. This GM bean line (named M1/4) was modified for resistance against Bean golden mosaic virus (BGMV) by expressing a mutated REP protein, which is essential for virus replication. Biosafety studies were performed for a period of three years under field conditions. The abundance of some species was significantly higher in specific treatments in a particular year, but not consistently different in other years. A regular pattern was not observed in the distribution of insects between genetically modified and conventional treatments. Data analyses showed that minor differences observed can be attri...

Fitopatologia Brasileira, 2002

Transgenic Research, 2011

We produced human growth hormone (hGH), a protein that stimulates growth and cell reproduction, i... more We produced human growth hormone (hGH), a protein that stimulates growth and cell reproduction, in genetically engineered soybean [Glycine max (L.) Merrill] seeds. Utilising the alpha prime (α') subunit of β-conglycinin tissue-specific promoter from soybean and the α-Coixin signal peptide from Coix lacryma-jobi, we obtained transgenic soybean lines that expressed the mature form of hGH in their seeds. Expression levels of bioactive hGH up to 2.9% of the total soluble seed protein content (corresponding to approximately 9 g kg(-1)) were measured in mature dry soybean seeds. The results of ultrastructural immunocytochemistry assays indicated that the recombinant hGH in seed cotyledonary cells was efficiently directed to protein storage vacuoles. Specific bioassays demonstrated that the hGH expressed in the soybean seeds was fully active. The recombinant hGH protein sequence was confirmed by mass spectrometry characterisation. These results demonstrate that the utilisation of tissue-specific regulatory sequences is an attractive and viable option for achieving high-yield production of recombinant proteins in stable transgenic soybean seeds.

RNA interference (RNAi) techniques are relevant in studies involving the search for improved nutr... more RNA interference (RNAi) techniques are relevant in studies involving the search for improved nutritional values in plants, and in the development of plants that are better adapted to different ecosystems, as well as optimal utilization of raw materials derived from plants for industrial use. RNAi evolved as a natural cellular defense mechanism against viruses, genomic confinement of retrotransposons, and as a cellular strategy for post-transcriptional regulation of gene expressions. A central feature in the mechanism of RNA inference is the participation of small RNA molecules. There are two types of small RNA molecules: small interfering RNAs (siRNA) and microRNA (miRNA). Several plants are resistant to viruses by virtue of an inherent double-stranded RNAs (dsRNA) and siRNA generating system whose targets are gene sequences essential for viral pathogenicity.

Proteomics

The seed-feeding beetle Callosobruchus maculatus is an important cowpea pest (Vigna unguiculata) ... more The seed-feeding beetle Callosobruchus maculatus is an important cowpea pest (Vigna unguiculata) as well as an interesting model to study insect digestive physiology. The larvae of C. maculatus rely on cysteine and aspartic peptidases to digest proteins in their diet. In this work, the global proteomic changes induced in the intestinal tract of larval C. maculatus challenged by the ingestion of cystatin, a cysteine peptidase inhibitor, was investigated by a nanoLC-MS/MS approach. The ingestion of cystatin caused a delay in the development of the larvae, but the mortality was not high, indicating that C. maculatus is able to adapt to this inhibitor. This proteomic strategy resulted in the identification of 752 and 550 protein groups in the midgut epithelia and midgut contents, respectively, and quantitative analyses allowed us to establish relative differences of the identified proteins. Ingestion of cystatin led to significant changes in the proteome of both the midgut epithelia and...

Plant Pathology, 2010

Pathogenesis of Sclerotinia sclerotiorum (white mould) has been associated with fungal secretion ... more Pathogenesis of Sclerotinia sclerotiorum (white mould) has been associated with fungal secretion of oxalic acid (OA). Enzymes capable of degrading OA have been utilized to produce transgenic resistant plants. Transgenic soybean lines containing the decarboxylase gene (oxdc) isolated from a Flammulina sp. were produced by the biolistic process. Molecular analysis revealed successful incorporation of the gene into the plant genome and showed that the oxdc gene was transferred to the progeny plants. Sixteen T 2 transgenic events were screened for S. sclerotiorum resistance using a detached leaf assay. The white mould disease progress curve displayed a significant delay in symptom development in all oxdc events compared with the nontransgenic genotype. Area under the disease progress curve (AUDPC) showed reduction in severity ranging from 61% to 96% comparing the oxdc events with the nontransgenic control. One event (OXDC.9.21) presented some plants that did not show any symptoms after 92 h. RT-PCR analysis for detection of oxdc gene transcripts suggested that expression of the oxdc gene is associated with resistance to S. sclerotiorum.

Plant Science, 1994

... evaluation of the strength of the Brazil nut 2S promoter in comparison with an analogous pro-... more ... evaluation of the strength of the Brazil nut 2S promoter in comparison with an analogous pro-moter from Arabidopsis and the 35S promoter from CaMV showed that the latter drives transientGUS-expression in ... [8] LAB De Castro, Z. Lacerda, RA Aramayo, MJ Sampaio and ES ...

Genetics and molecular research : GMR, 2007

Evaluation of transgenic crops under field conditions is a fundamental step for the production of... more Evaluation of transgenic crops under field conditions is a fundamental step for the production of genetically engineered varieties. In order to determine if there is pollen dispersal from transgenic to nontransgenic soybean plants, a field release experiment was conducted in the Cerrado region of Brazil. Nontransgenic plants were cultivated in plots surrounding Roundup Ready transgenic plants carrying the cp4 epsps gene, which confers herbicide tolerance against glyphosate herbicide, and pollen dispersal was evaluated by checking for the dominant gene. The percentage of cross-pollination was calculated as a fraction of herbicide-tolerant and -nontolerant plants. The greatest amount of transgenic pollen dispersion was observed in the first row, located at one meter from the central (transgenic) plot, with a 0.52% average frequency. The frequency of pollen dispersion decreased to 0.12% in row 2, reaching 0% when the plants were up to 10 m distance from the central plot. Under these co...

Plant molecular biology, 1997

The expression of Brazil nut storage albumin genes is highly regulated during seed development. S... more The expression of Brazil nut storage albumin genes is highly regulated during seed development. Several sequences in the promoter of one of these genes show homologies with the target sites of the maize O2 bZIP regulatory protein. We therefore asked whether the O2 protein would recognize these promoter sequences. We show that the O2 protein binds to three different sequences (F1, F2 and F3). F1 and F3 are hybrid C/G and A/G boxes, respectively, that are homologous to the O2-binding site of a maize alpha-zein gene. F2 is a new O2-binding sequence related to the O2 target sites of the Coix alpha-coxin, the maize b-32 genes and the AP-1 pseudopalindrome. Molecular modelling showed that an Asn and a Ser in the 02 DNA binding domain make different base-specific contacts with each operator. 5' Promoter deletions of the be2S1 gene showed that the domain containing the O2 target sites F1 and F2 is required for detectable reporter gene expression in transgenic tobacco seeds. Moreover, th...

Genetics and molecular research : GMR, 2005

An association of two techniques, nuclear transfer (NT), and transfection of somatic animal cells... more An association of two techniques, nuclear transfer (NT), and transfection of somatic animal cells, has numerous potential applications and considerable impact, mainly in agriculture, medicine, pharmacy, and fundamental biology. In addition, somatic cell nuclear transfer is the most efficient alternative to produce large transgenic animals. We compared in vitro and in vivo developmental capacities of NT using fibroblast cells isolated from a 14-month-old cloned Simmental heifer (FCE) vs the same line transfected with a plasmid containing neomycin-resistant genes (TFCE). There were no significant differences (P > 0.5) in either fusion (116/149 = 78% vs 216/301 = 72%), cleavage (78/116 = 67% vs 141/216 = 65%) and blastocyst (35/116 = 30% vs 52/216 = 24%) rates or in pregnancy rate at 30 to 35 days after embryo transfer (2/17 vs 3/17) between NT using FCE and TFCE, respectively. Transfection and long-term in vitro culture of transfected cells did not affect developmental capacity of ...

Methods in molecular biology (Clifton, N.J.), 2015

RNA interference (RNAi) has emerged as a leading technology in designing genetically modified cro... more RNA interference (RNAi) has emerged as a leading technology in designing genetically modified crops engineered to resist viral infection. The last decades have seen the development of a large number of crops whose inherent posttranscriptional gene silencing mechanism has been exploited to target essential viral genes through the production of dsRNA that triggers an endogenous RNA-induced silencing complex (RISC), leading to gene silencing in susceptible viruses conferring them with resistance even before the onset of infection. Selection and breeding events have allowed for establishing this highly important agronomic trait in diverse crops. With improved techniques and the availability of new data on genetic diversity among several viruses, significant progress is being made in engineering plants using RNAi with the release of a number of commercially available crops. Biosafety concerns with respect to consumption of RNAi crops, while relevant, have been addressed, given the fact t...

Genetics and molecular research : GMR, 2005

The development of an efficient transfection system in livestock cells is an important step towar... more The development of an efficient transfection system in livestock cells is an important step towards investigating gene transfer and the functioning and production of transgenic animals. Important factors involved in cationic liposome mediated gene transfer were evaluated through in vitro transfection of bovine, caprine and ovine fibroblast cells. Transfection of plasmid DNA complexes of different commercially available liposomes (Lipofectamine, Lipofectin, Cellfectin and DMRIE-C; Gibco-BRL, USA) was evaluated utilizing the following parameters: DNA/liposome ratio, cell density, DNA conformation, and the effect of transfection time on the efficiency of bovine fibroblasts to express a reporter gene. The effects and concentrations of liposomes were also evaluated in caprine and ovine fibroblasts. Lipofectamine alone and Lipofectamine with Plus reagent induced high-frequency expression of beta-galactosidase and neo genes in all cells evaluated (47 and 88.3%, respectively). Regarding phe...

Plos One, 2012

Starting from the premise that a wealth of potentially biologically active peptides may lurk with... more Starting from the premise that a wealth of potentially biologically active peptides may lurk within proteins, we describe here a methodology to identify putative antimicrobial peptides encrypted in protein sequences. Candidate peptides were identified using a new screening procedure based on physicochemical criteria to reveal matching peptides within protein databases. Fifteen such peptides, along with a range of natural antimicrobial peptides, were examined using DSC and CD to characterize their interaction with phospholipid membranes. Principal component analysis of DSC data shows that the investigated peptides group according to their effects on the main phase transition of phospholipid vesicles, and that these effects correlate both to antimicrobial activity and to the changes in peptide secondary structure. Consequently, we have been able to identify novel antimicrobial peptides from larger proteins not hitherto associated with such activity, mimicking endogenous and/or exogenous microorganism enzymatic processing of parent proteins to smaller bioactive molecules. A biotechnological application for this methodology is explored. Soybean (Glycine max) plants, transformed to include a putative antimicrobial protein fragment encoded in its own genome were tested for tolerance against Phakopsora pachyrhizi, the causative agent of the Asian soybean rust. This procedure may represent an inventive alternative to the transgenic technology, since the genetic material to be used belongs to the host organism and not to exogenous sources.

Revista da Sociedade Brasileira de Medicina Tropical, 1999

Resumo O objetivo do trabalho é medir as coberturas das atividades municipais de controle de Aede... more Resumo O objetivo do trabalho é medir as coberturas das atividades municipais de controle de Aedes aegypti e/ou Aedes albopictus, o casa-casa eo arrastão, realizadas entre 1989 e 1995 na região de São José do Rio Preto, São Paulo e avaliar a correlação cruzada entre elas ...

Plant Science, 2006

The rep gene of Bean golden mosaic virus (BGMV) is essential for virus replication. A mutated rep... more The rep gene of Bean golden mosaic virus (BGMV) is essential for virus replication. A mutated rep gene with amino acid codon change in the putative nucleoside triphosphate (NTP) binding motif D262R was created. Phaseolus vulgaris transformation was achieved with a vector that contained the mutated rep and bar genes. A total of 17 initial (T 0 ) transformants were analyzed. One line (M1/4) showed tolerance to glufosinate ammonium and partial resistance to the virus, that is, disease incidence depended on inoculation level. The incidence of BGMV increased with the increasing number of viruliferous whiteflies per plant, both in the transgenic and in the control plants. However, the number of symptomless plants was significantly higher in the transgenic group. The line M1/4 was studied during several generations and presented stability in the transgene loci and virus resistance. Southern blot analysis with genomic DNA of eight generations led to an estimate of two copies of the rep gene integrated at the same locus. RT-PCR analysis revealed the presence of both bar and rep genes transcripts. The mutated REP protein was present in amounts detectable by Western blot analysis in transgenic plants. #

Common bean is grown and consumed principally in developing countries in Latin America, Africa, a... more Common bean is grown and consumed principally in developing countries in Latin America, Africa, and Asia. It is largely a subsistence crop eaten by its producers and, hence, is underestimated in production and commerce statistics. Common bean is a major source of dietary protein, which complements carbohydrate-rich sources such as rice, maize, and cassava. It is also a rich source

Fems Microbiology Letters, 2000

Metarhizium anisopliae var. acridum (syn. M. flavoviride) is recognized as a highly specific and ... more Metarhizium anisopliae var. acridum (syn. M. flavoviride) is recognized as a highly specific and virulent mycopathogen of locusts and grasshoppers and is currently being developed as a biological control agent for this group of insects in Brazil. Intact conidia of M. anisopliae var. acridum strain CG423 were transformed using microparticle bombardment. Plasmids used were: (1) pBARKS1 carrying the bar gene

GM crops & food

Genetically modified (GM) crops is considered the fastest adopted crop technology in the history ... more Genetically modified (GM) crops is considered the fastest adopted crop technology in the history of modern agriculture. However, possible undesirable and unintended effects must be considered during the research steps toward development of a commercial product. In this report we evaluated effects of a common bean virus resistant line on arthropod populations, considered as non-target organisms. This GM bean line (named M1/4) was modified for resistance against Bean golden mosaic virus (BGMV) by expressing a mutated REP protein, which is essential for virus replication. Biosafety studies were performed for a period of three years under field conditions. The abundance of some species was significantly higher in specific treatments in a particular year, but not consistently different in other years. A regular pattern was not observed in the distribution of insects between genetically modified and conventional treatments. Data analyses showed that minor differences observed can be attri...

Fitopatologia Brasileira, 2002

Transgenic Research, 2011

We produced human growth hormone (hGH), a protein that stimulates growth and cell reproduction, i... more We produced human growth hormone (hGH), a protein that stimulates growth and cell reproduction, in genetically engineered soybean [Glycine max (L.) Merrill] seeds. Utilising the alpha prime (α') subunit of β-conglycinin tissue-specific promoter from soybean and the α-Coixin signal peptide from Coix lacryma-jobi, we obtained transgenic soybean lines that expressed the mature form of hGH in their seeds. Expression levels of bioactive hGH up to 2.9% of the total soluble seed protein content (corresponding to approximately 9 g kg(-1)) were measured in mature dry soybean seeds. The results of ultrastructural immunocytochemistry assays indicated that the recombinant hGH in seed cotyledonary cells was efficiently directed to protein storage vacuoles. Specific bioassays demonstrated that the hGH expressed in the soybean seeds was fully active. The recombinant hGH protein sequence was confirmed by mass spectrometry characterisation. These results demonstrate that the utilisation of tissue-specific regulatory sequences is an attractive and viable option for achieving high-yield production of recombinant proteins in stable transgenic soybean seeds.