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1.
J Appl Anim Welf Sci ; 23(4): 424-432, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31615277

RESUMO

A yoke is an interface between bullock power and actual work to be performed. The yoke is worn on the neck of the bullocks and is secured by a belt around the neck. The bullocks push the yoke with their shoulders, hump and neck; therefore, the work is performed. Neck of the bullock is subjected to a high pressure which damages the body tissues. Consequently, bullocks are subjected to injuries, pain and fatigue that limit their performance. The neck seats are shaped similar to the neck profile of the bullocks which ensures high contact area between animal body and neck seat leading to lesser pressure and more animal comfort. The neck of a bullock was digitized using an optical scanner and a large number of points were obtained. The 3-D model was created on the digitized points, and the neck seat was developed subsequently. The contact analysis was performed using the augmented Lagrangian formulation option of Ansys Workbench for predicting contact pressure. The results of the body contoured yoke are compared with that of a flat wooden plank yoke and a cylindrical yoke. A substantial reduction of contact pressure and indentation on the neck has been found for the body contoured yoke. Conversely, the contact pressure was found much higher for other two types of yokes.


Assuntos
Criação de Animais Domésticos/instrumentação , Bem-Estar do Animal , Imageamento Tridimensional/veterinária , Animais , Bovinos/anatomia & histologia , Imageamento Tridimensional/métodos , Masculino , Pescoço/anatomia & histologia
3.
PLoS One ; 11(12): e0167702, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27942031

RESUMO

A comprehensive germplasm evaluation study of wheat accessions conserved in the Indian National Genebank was conducted to identify sources of rust and spot blotch resistance. Genebank accessions comprising three species of wheat-Triticum aestivum, T. durum and T. dicoccum were screened sequentially at multiple disease hotspots, during the 2011-14 crop seasons, carrying only resistant accessions to the next step of evaluation. Wheat accessions which were found to be resistant in the field were then assayed for seedling resistance and profiled using molecular markers. In the primary evaluation, 19,460 accessions were screened at Wellington (Tamil Nadu), a hotspot for wheat rusts. We identified 4925 accessions to be resistant and these were further evaluated at Gurdaspur (Punjab), a hotspot for stripe rust and at Cooch Behar (West Bengal), a hotspot for spot blotch. The second round evaluation identified 498 accessions potentially resistant to multiple rusts and 868 accessions potentially resistant to spot blotch. Evaluation of rust resistant accessions for seedling resistance against seven virulent pathotypes of three rusts under artificial epiphytotic conditions identified 137 accessions potentially resistant to multiple rusts. Molecular analysis to identify different combinations of genetic loci imparting resistance to leaf rust, stem rust, stripe rust and spot blotch using linked molecular markers, identified 45 wheat accessions containing known resistance genes against all three rusts as well as a QTL for spot blotch resistance. The resistant germplasm accessions, particularly against stripe rust, identified in this study can be excellent potential candidates to be employed for breeding resistance into the background of high yielding wheat cultivars through conventional or molecular breeding approaches, and are expected to contribute toward food security at national and global levels.


Assuntos
Bases de Dados Genéticas , Resistência à Doença , Triticum/genética , Ascomicetos/patogenicidade , Índia , Locos de Características Quantitativas , Triticum/classificação , Triticum/imunologia , Triticum/microbiologia
4.
BMC Genet ; 17(1): 127, 2016 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-27597653

RESUMO

BACKGROUND: The knowledge of the extent and pattern of diversity in the crop species is a prerequisite for any crop improvement as it helps breeders in deciding suitable breeding strategies for their future improvement. Rice is the main staple crop in India with the large number of varieties released every year. Studies based on the small set of rice genotypes have reported a loss in genetic diversity especially after green revolution. However, a detailed study of the trend of diversity in Indian rice varieties is lacking. SSR markers have proven to be a marker of choice for studying the genetic diversity. Therefore, the present study was undertaken with the aim to characterize and assess trends of genetic diversity in a large set of Indian rice varieties (released between 1940-2013), conserved in the National Gene Bank of India using SSR markers. RESULT: A set of 729 Indian rice varieties were genotyped using 36 HvSSR markers to assess the genetic diversity and genetic relationship. A total of 112 alleles was amplified with an average of 3.11 alleles per locus with mean Polymorphic Information Content (PIC) value of 0.29. Cluster analysis grouped these varieties into two clusters whereas the model based population structure divided them into three populations. AMOVA study based on hierarchical cluster and model based approach showed 3 % and 11 % variation between the populations, respectively. Decadal analysis for gene diversity and PIC showed increasing trend from 1940 to 2005, thereafter values for both the parameters showed decreasing trend between years 2006-2013. In contrast to this, allele number demonstrated increasing trend in these varieties released and notified between1940 to 1985, it remained nearly constant during 1986 to 2005 and again showed an increasing trend. CONCLUSION: Our results demonstrated that the Indian rice varieties harbors huge amount of genetic diversity. However, the trait based improvement program in the last decades forced breeders to rely on few parents, which resulted in loss of gene diversity during 2006 to 2013. The present study indicates the need for broadening the genetic base of Indian rice varieties through the use of diverse parents in the current breeding program.


Assuntos
Variação Genética , Repetições de Microssatélites , Oryza/genética , Alelos , Análise por Conglomerados , Frequência do Gene , Marcadores Genéticos , Genética Populacional , Genótipo , Filogenia
5.
PLoS One ; 9(11): e113094, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25412256

RESUMO

The North-Eastern region (NER) of India, comprising of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura, is a hot spot for genetic diversity and the most probable origin of rice. North-east rice collections are known to possess various agronomically important traits like biotic and abiotic stress tolerance, unique grain and cooking quality. The genetic diversity and associated population structure of 6,984 rice accessions, originating from NER, were assessed using 36 genome wide unlinked single nucleotide polymorphism (SNP) markers distributed across the 12 rice chromosomes. All of the 36 SNP loci were polymorphic and bi-allelic, contained five types of base substitutions and together produced nine types of alleles. The polymorphic information content (PIC) ranged from 0.004 for Tripura to 0.375 for Manipur and major allele frequency ranged from 0.50 for Assam to 0.99 for Tripura. Heterozygosity ranged from 0.002 in Nagaland to 0.42 in Mizoram and gene diversity ranged from 0.006 in Arunachal Pradesh to 0.50 in Manipur. The genetic relatedness among the rice accessions was evaluated using an unrooted phylogenetic tree analysis, which grouped all accessions into three major clusters. For determining population structure, populations K = 1 to K = 20 were tested and population K = 3 was present in all the states, with the exception of Meghalaya and Manipur where, K = 5 and K = 4 populations were present, respectively. Principal Coordinate Analysis (PCoA) showed that accessions were distributed according to their population structure. AMOVA analysis showed that, maximum diversity was partitioned at the individual accession level (73% for Nagaland, 58% for Arunachal Pradesh and 57% for Tripura). Using POWERCORE software, a core set of 701 accessions was obtained, which accounted for approximately 10% of the total NE India collections, representing 99.9% of the allelic diversity. The rice core set developed will be a valuable resource for future genomic studies and crop improvement strategies.


Assuntos
Oryza/classificação , Oryza/genética , Polimorfismo de Nucleotídeo Único , Sementes/genética , Cromossomos de Plantas , Biologia Computacional/métodos , Evolução Molecular , Índia , Filogenia , Software
6.
PLoS One ; 8(12): e84136, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24367635

RESUMO

Simple sequence repeat (SSR) and Single Nucleotide Polymorphic (SNP), the two most robust markers for identifying rice varieties were compared for assessment of genetic diversity and population structure. Total 375 varieties of rice from various regions of India archived at the Indian National GeneBank, NBPGR, New Delhi, were analyzed using thirty six genetic markers, each of hypervariable SSR (HvSSR) and SNP which were distributed across 12 rice chromosomes. A total of 80 alleles were amplified with the SSR markers with an average of 2.22 alleles per locus whereas, 72 alleles were amplified with SNP markers. Polymorphic information content (PIC) values for HvSSR ranged from 0.04 to 0.5 with an average of 0.25. In the case of SNP markers, PIC values ranged from 0.03 to 0.37 with an average of 0.23. Genetic relatedness among the varieties was studied; utilizing an unrooted tree all the genotypes were grouped into three major clusters with both SSR and SNP markers. Analysis of molecular variance (AMOVA) indicated that maximum diversity was partitioned between and within individual level but not between populations. Principal coordinate analysis (PCoA) with SSR markers showed that genotypes were uniformly distributed across the two axes with 13.33% of cumulative variation whereas, in case of SNP markers varieties were grouped into three broad groups across two axes with 45.20% of cumulative variation. Population structure were tested using K values from 1 to 20, but there was no clear population structure, therefore Ln(PD) derived Δk was plotted against the K to determine the number of populations. In case of SSR maximum Δk was at K=5 whereas, in case of SNP maximum Δk was found at K=15, suggesting that resolution of population was higher with SNP markers, but SSR were more efficient for diversity analysis.


Assuntos
Repetições de Microssatélites , Oryza/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Marcadores Genéticos/genética , Índia , Dinâmica Populacional , Estatística como Assunto
7.
Cryo Letters ; 24(2): 119-24, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12819833

RESUMO

Pollen of 12 genotypes of the annual soybean and its wild perennial relatives were stored without pre-desiccation at low temperatures (-20 C and -196 C) and tested for their viability in vitro. The influence of cryopreserved pollen on pod set and seed production was also investigated. Cryopreserved pollen of all the genotypes showed germination in vitro. Pollen of annual soybean stored at -20 C retained their viability for 4 months, however, pollen of its wild perennial relatives at same storage conditions failed to germinate in vitro. Flowers pollinated with cryopreserved pollen had similar pod set and number of seeds/pod as those pollinated with fresh pollen. Results of this study suggest that cryopreservation of pollen can be used successfully for soybean breeding, and also offers the possibility of conserving the haploid gene pool of soybean and wild perennial species in a cryobank facility.


Assuntos
Adaptação Fisiológica/fisiologia , Criopreservação/métodos , Glycine max/fisiologia , Pólen/fisiologia , Sobrevivência Celular/fisiologia , Fertilidade/fisiologia , Germinação/fisiologia , Valores de Referência , Análise de Sobrevida
8.
Ann N Y Acad Sci ; 949: 44-57, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11795379

RESUMO

Androgens are C-19 steroids secreted primarily from the testes and adrenals that play a critical role in reproduction. Reproductive functions of androgens are mediated through coordination of diverse physiological processes ranging from brain functions to specific cell proliferation and apoptosis. At the molecular level, most of these regulatory influences are exerted by altered expression of appropriate genes by the androgen receptor (AR), a member of the nuclear receptor (NR) superfamily. The unliganded AR is a cytoplasmic protein and, upon ligand binding, it translocates into the nucleus. Thereafter, in conjunction with other transcription factors and coactivators, the AR influences transcription of target genes through a multistep process that includes its clustering in a subnuclear compartment. Here, we describe the genomic organization of the AR, the role of individual structural domains in specific AR function, and the influence of agonistic/antagonistic ligands in the intracellular movement of the receptor. We also show that the AR is capable of undergoing multiple rounds of nucleocytoplasmic recycling after ligand binding and dissociation. Xenobiotic ligands, considered as selective androgen receptor modulators (SARMs), can modulate AR activity by inhibiting either its nuclear translocation or its subnuclear clustering and subsequent transactivation function.


Assuntos
Receptores Androgênicos/fisiologia , Glândulas Suprarrenais/fisiologia , Antagonistas de Androgênios/farmacologia , Animais , Di-Hidrotestosterona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Ligantes , Masculino , Receptores Androgênicos/química , Receptores Androgênicos/genética , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/fisiologia , Testículo/fisiologia , Transcrição Gênica
9.
Mol Endocrinol ; 14(8): 1162-74, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10935541

RESUMO

An expression construct containing the cDNA encoding a modified aequorea green fluorescent protein (GFP) ligated to the 5'-end of the rat androgen receptor (AR) cDNA (GFP-AR) was used to study the intracellular dynamics of the receptor movement in living cells. In three different cell lines, ie. PC3, HeLa, and COS1, unliganded GFP-AR was seen mostly in the cytoplasm and rapidly (within 15-60 min) moved to the nuclear compartment after androgen treatment. Upon androgen withdrawal, the labeled AR migrated back to the cytoplasmic compartment and maintained its ability to reenter the nucleus on subsequent exposure to androgen. Under the condition of inhibited protein synthesis by cycloheximide (50 microg/ml), at least four rounds of receptor recycling after androgen treatment and withdrawal were recorded. Two nonandrogenic hormones, 17beta-estradiol and progesterone at higher concentrations (10(-7)/10(-6) M), were able to both transactivate the AR-responsive promoter and translocate the GFP-AR into the nucleus. Similarly, antiandrogenic ligands, cyproterone acetate and casodex, were also capable of translocating the cytoplasmic AR into the nucleus albeit at a slower rate than the androgen 5alpha-dihydrotestosterone (DHT). All AR ligands with transactivation potential, including the mixed agonist/antagonist cyproterone acetate, caused translocation of the GFP-AR into a subnuclear compartment indicated by its punctate intranuclear distribution. However, translocation caused by casodex, a pure antagonist, resulted in a homogeneous nuclear distribution. Subsequent exposure of the casodex-treated cell to DHT rapidly (15-30 min) altered the homogeneous to punctate distribution of the already translocated nuclear AR. When transported into the nucleus either by casodex or by DHT, GFP-AR was resistant to 2 M NaCl extraction, indicating that the homogeneously distributed AR is also associated with the nuclear matrix. Taken together, these results demonstrate that AR requires ligand activation for its nuclear translocation where occupancy by only agonists and partial agonists can direct it to a potentially functional subnuclear location and that one receptor molecule can undertake multiple rounds of hormonal signaling; this indicates that ligand dissociation/inactivation rather than receptor degradation may play a critical role in terminating hormone action.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Receptores Androgênicos/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Antagonistas de Androgênios/farmacologia , Anilidas/farmacologia , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Compartimento Celular , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Ciproterona/farmacologia , Citoplasma/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Estradiol/farmacologia , Ácidos Graxos Insaturados/farmacologia , Proteínas de Fluorescência Verde , Humanos , Cinética , Ligantes , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Nitrilas , Progesterona/farmacologia , Ratos , Receptores Androgênicos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Compostos de Tosil , Ativação Transcricional
10.
Mol Endocrinol ; 13(6): 925-34, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10379891

RESUMO

Estrogen receptor (ER) functions as a ligand-activated transcription factor for estrogen-regulated genes. Because of the critical role of the ER in the proliferation of certain estrogen-dependent cancer cell types such as the mammary tumor, inhibitors of estrogen action at the level of receptor function are of major clinical interest. Here we describe developments of two ribozymes that can selectively degrade the human ER mRNA and inhibit trans-activation of an artificial promoter containing the estrogen response element. Two ribozymes, designated RZ-1 and RZ-2, cleave the human ER alpha mRNA at nucleotide positions +956 and +889, respectively. These cleavage sites lie within the coding sequence for the DNA-binding domain of the receptor protein. Both RZ-1 and RZ-2 were also effective in inhibiting the progression of quiescent MCF-7 breast cancer cells to the S phase of the cell cycle after their exposure to 17beta-estradiol (10(-9) M). These results provide a new avenue for inhibition of estrogen action by selective mRNA degradation with its potential therapeutic application through targeted gene delivery vectors.


Assuntos
RNA Catalítico/metabolismo , RNA Mensageiro/metabolismo , Receptores de Estrogênio/genética , Animais , Sequência de Bases , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Células COS/metabolismo , Ciclo Celular/genética , Receptor alfa de Estrogênio , Feminino , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , RNA Catalítico/genética , RNA Mensageiro/química , Receptores de Estrogênio/metabolismo , Elementos de Resposta , Fase S/genética , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
11.
Eur J Biochem ; 258(1): 68-77, 1998 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9851693

RESUMO

In a 31P-NMR spectroscopic study of cultured M2R mouse melanoma cells, we previously demonstrated the acute stimulation of three peaks in the phosphomonoester region of the spectrum by [Ahx4, DPhe7]alpha-melanotropin (concomitant with an increase in cellular adenosine 3',5'-phosphate (cAMP) and a decrease in ATP [Degani, H., DeJordy, J. O. & Salomon, Y. (1991) Proc. Natl Acad. Sci. USA 88, 1506-1510]. Chemical identification of these metabolites was performed in this study using 32P metabolic labeling and polyethyleneimine-cellulose thin layer chromatography in combination with 31P-NMR and 13C-NMR spectroscopic methods. Two of the stimulated signals were identified as P1 and P6 of fructose 1,6-bisphosphate (FruP2) and their mode of regulation by alpha-melanotropin was examined. The FruP2 response to alpha-melanotropin coincided in time and dose with a rise in cAMP and a decrease in levels of ATP, while elevation of cAMP by forskolin alone did not increase FruP2. The stimulatory effect of alpha-melanotropin was not associated with a change in the overall rate of glycolysis, suggesting that FruP2 levels were not rate limiting in this process. The data suggest the presence of a previously unknown response of M2R melanoma cells to alpha-melanotropin, which coincides in time with enhanced cAMP accumulation but is not mediated by cAMP and may relate to the control of FruP2 in a non glycolytic context.


Assuntos
Frutosedifosfatos/biossíntese , Melanoma Experimental/metabolismo , alfa-MSH/fisiologia , Animais , Isótopos de Carbono , AMP Cíclico/metabolismo , Ésteres , Espectroscopia de Ressonância Magnética , Melanoma Experimental/patologia , Camundongos , Isótopos de Fósforo , Células Tumorais Cultivadas , alfa-MSH/análogos & derivados , alfa-MSH/farmacologia
12.
Mol Endocrinol ; 12(11): 1684-95, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9817595

RESUMO

Steroid hormone receptors are, in most cases, mainly nuclear proteins that undergo a continuous nucleocytoplasmic shuttling. The mechanism of the nuclear export of these proteins remains largely unknown. To approach this problem experimentally in vivo, we have prepared cell lines permanently coexpressing the wild-type nuclear progesterone receptor (PR) and a cytoplasmic receptor mutant deleted of its nuclear localization signal (NLS) [(deltaNLS)PR]. Each receptor species was deleted from the epitope recognized by a specific monoclonal antibody, thus allowing separated observation of the two receptor forms in the same cells. Administration of hormone provoked formation of heterodimers during nucleocytoplasmic shuttling and import of (deltaNLS)PR into the nucleus. Washing out of the hormone allowed us to follow the export of (deltaNLS)PR into the cytoplasm. Microinjection of BSA coupled to a NLS inhibited the export of (deltaNLS)PR. On the contrary, microinjection of BSA coupled to a nuclear export signal (NES) was without effect. Moreover, leptomycin B, which inhibits NES-mediated export, was also without effect. tsBN2 cells contain a thermosensitive RCC1 protein (Ran GTP exchange protein). At the nonpermissive temperature, the nuclear export of (deltaNLS)PR could be observed, whereas the export of NES-BSA was suppressed. Microinjection of GTPgammaS confirmed that the export of (deltaNLS)PR was not dependent on GTP hydrolysis. These experiments show that the nuclear export of PR is not NES mediated but probably involves the NLS. It does not involve Ran GTP, and it is not dependent on the hydrolysis of GTP. The nucleocytoplasmic shuttling of steroid hormone receptors thus appears to utilize mechanisms different from those previously described for some viral, regulatory, and heterogeneous ribonuclear proteins.


Assuntos
Proteínas de Ciclo Celular , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Troca do Nucleotídeo Guanina , Proteínas Nucleares/metabolismo , Sinais Direcionadores de Proteínas/metabolismo , Receptores de Progesterona/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico/efeitos dos fármacos , Células COS , Células Cultivadas , Cricetinae , Proteínas de Ligação a DNA/genética , Ácidos Graxos Insaturados/farmacologia , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Trifosfato/fisiologia , Humanos , Rim , Células L , Mesocricetus , Camundongos , Microinjeções , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/metabolismo , Progesterona/farmacologia , Deleção de Sequência , Soroalbumina Bovina/metabolismo , Proteína ran de Ligação ao GTP
13.
Magn Reson Med ; 35(2): 194-200, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8622583

RESUMO

A method for simultaneous extraction of lipids and water-soluble metabolites from a single cell sample was developed and optimized for NMR spectroscopy. Intermediary metabolites in cultured M2R mouse melanoma cells and changes therein in response to challenge with melanotropin were studied by 31P and 13C NMR. Cells were extracted with methanol, chloroform, and water (1:1:1, v/v/v). The contents of the chloroform and methanol-water phases were separated and quantitatively recovered. The contents of the upper and lower phases compared well with the homologous fractions obtained by perchloric acid and Folch's lipid extraction methods. The pH of the extracts remained within the physiologic range, eliminating potential deleterious effect on cellular metabolites. The water phase contained minimal amounts of salts, making these extracts amenable to subsequent analytical procedures. Obtaining lipid- and water-soluble metabolites from the same sample enables characterization of metabolic pathways that bridge the two cellular components in a quantitative manner.


Assuntos
Espectroscopia de Ressonância Magnética , Melanoma Experimental/química , Fosfolipídeos/análise , Animais , Camundongos , Solubilidade , Células Tumorais Cultivadas/química
14.
Protein Expr Purif ; 5(6): 527-33, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7858420

RESUMO

The present report documents an improved enzyme assay method for the mammalian L-alanine:4,5-dioxovalerate transaminase which is of significant utility in work with crude tissue homogenates, cell cultures, or purified enzyme preparations. We also describe a new and rapid purification procedure for this enzyme from rat kidney mitochondria. The three-step procedure involves the use of digitonin and lubrol for mitochondrial matrix preparation and L-alanine-Sepharose 4B column chromatography followed by gel filtration on Sepharose 6B. By this procedure it is possible to obtain a highly purified enzyme preparation in a relatively short time with a 37.5% yield.


Assuntos
Rim/enzimologia , Transaminases/isolamento & purificação , Animais , Cromatografia de Afinidade , Cromatografia em Gel , Reações Cruzadas , Digitonina , Mitocôndrias/enzimologia , Mitocôndrias Hepáticas/enzimologia , Polietilenoglicóis , Testes de Precipitina , Ratos , Transaminases/química , Transaminases/imunologia
15.
Electrophoresis ; 14(8): 826-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8404829

RESUMO

In the present communication, we describe a method for the determination of both the native and subunit molecular weight of a protein by a single pore limit electrophoretic run. When native proteins and sodium dodecyl sulfate (SDS)-heat denatured proteins were electrophoresed in a 4-28% gradient-polyacrylamide gel, in the presence of 0.02% SDS in running buffer, their respective molecular weights (native and subunit) could be determined by comparing the migration distances of unknown and standard proteins. The presence of SDS up to 0.02% in the running buffer did not dissociate the native proteins into their subunits. The linearity in distribution of native and SDS-polyacrylamide gel electrophoresis (PAGE) standard marker proteins used for the molecular weight determination further showed the efficacy of the present technique.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Proteínas/química , Catalase/química , Ferritinas/química , Peso Molecular , Transaminases/química
16.
J Biochem ; 113(5): 557-62, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-7687993

RESUMO

A specific rabbit antibody was prepared against rat kidney mitochondrial L-alanine: 4,5-dioxovalerate transaminase, which is one of the two enzymes catalyzing the synthesis of delta-aminolevulinic acid in the heme biosynthetic pathway. Total polyadenylated RNA isolated from rat kidney was translated in vitro using rabbit reticulocyte cell-free translation system, and L-alanine:4,5-dioxovalerate transaminase was estimated by indirect immunoprecipitation to represent 0.85% of the total translation product. When the total in vitro translated product was incubated with homologous kidney mitochondria, 59% of the [35S]methionine labeled enzyme was translocated into the mitochondria where it was no longer accessible to externally added protease. In relation to total protein translocation, the translocation of L-alanine:4,5-dioxovalerate transaminase remained unaltered by addition of hemin up to 50 microM. These results show that, unlike the other enzyme of the heme biosynthetic pathway (delta-aminolevulinic acid synthetase), this enzyme is not under tight control by heme, but nonetheless, functions as an important source to maintain a housekeeping level of delta-aminolevulinic acid.


Assuntos
Ácido Aminolevulínico/metabolismo , Rim/metabolismo , Mitocôndrias/metabolismo , Transaminases/metabolismo , Aminoácidos/análise , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Hemina/farmacologia , Técnicas In Vitro , Rim/ultraestrutura , Poli A/genética , Poli A/metabolismo , Biossíntese de Proteínas , RNA/genética , RNA/metabolismo , RNA Mensageiro , Ratos , Ratos Wistar , Transaminases/química , Transaminases/imunologia , Transaminases/isolamento & purificação
17.
Theor Appl Genet ; 87(3): 343-6, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24190260

RESUMO

Pollen grains and whole plants of 11 cultivars of oilseed brassicas (B. juncea,B. campestris,B. carinata) were screened for salt tolerance. Whereas pollen germination percentage in sitting drop cultures served as a reliable index of pollen tolerance to NaCl, pollen-tube growth did not. Seed yield in plants of the same 11 cultivars raised in artificially salinized soils also proved to be a good index of whole plant tolerance to soil salinity. A close correspondence between pollen (gametophyte) and whole plant (sporophyte) responses to salinity was discovered. Our studies show that tolerance to salt is yet another trait expressed in both the sporophyte and gametophyte.

18.
Eur J Biochem ; 198(3): 581-7, 1991 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2050138

RESUMO

L-Alanine:4,5-dioxovalerate transaminase was detected in the kidney cytosolic fraction with a lower specific activity than the mitochondrial enzyme. The enzyme was purified from the cytosol to homogeneity with a yield of 32%, and comparative analysis with the mitochondrial form was performed. Both forms of the enzyme have identical pH and temperature optima and also share common antigenic determinants. However, differences in their molecular properties exist. The molecular mass of the native cytoplasmic enzyme is 260 kDa, whereas that of the mitochondrial enzyme is 210 kDa. In addition, the cytoplasmic L-alanine: 4,5-dioxovalerate transaminase had a homopolymeric subunit molecular mass of 67 kDa compared to a subunit molecular mass of 50 kDa for the mitochondrial L-alanine:4,5-dioxovalerate transaminase. This is the first report of two forms of L-alanine:4,5-dioxovalerate transaminase. The different responses of cytosolic and mitochondrial L-alanine:4,5-dioxovalerate transaminases to hemin supplementation both in vitro and in vivo was demonstrated. Maximum inhibition of mitochondrial L-alanine:4,5-dioxovalerate transaminase activity was demonstrated with hemin injected at a dose of 1.2 mg/kg body mass, whereas the same dose of hemin stimulated the cytosolic enzyme to 150% of the control. A one-dimensional peptide map of partially digested cytosolic and mitochondrial L-alanine:4,5-dioxovalerate transaminase shows that the two forms of the enzymes are structurally related. Partial digestion of the cytosolic form of the enzyme with papain generated a fragment of 50 kDa which was identical to that of the undigested mitochondrial form (50 kDa). Moreover, papain digestion resulted in a threefold increase in cytosolic enzyme activity over the native enzyme, and such enhancement was comparable to the activity of the mitochondrial form of the enzyme. Therefore, we conclude that the cytosolic form of L-alanine: 4,5-dioxovalerate transaminase is different from the mitochondrial enzyme. Furthermore, immunoblot analysis indicated that the mitochondrial enzyme has antigenic similarity to the cytosolic enzyme as well as to the papain-digested cytosolic enzyme 50-kDa fragment.


Assuntos
Isoenzimas/metabolismo , Rim/enzimologia , Mitocôndrias/enzimologia , Transaminases/metabolismo , Animais , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Citosol/enzimologia , Heme/farmacologia , Isoenzimas/isolamento & purificação , Cinética , Masculino , Peso Molecular , Papaína/farmacologia , Ratos , Ratos Endogâmicos , Frações Subcelulares/enzimologia , Transaminases/isolamento & purificação
19.
Biochem Int ; 23(5): 999-1006, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1883406

RESUMO

The bulk of the enzyme L-alanine: 4,5-dioxovalerate transaminase, which catalyses the transamination reaction between L-alanine and 4,5-dioxovalerate to synthesize delta-aminolevulinic acid was predominantly recovered in the mitochondrial matrix. Sub-fractionation procedure of the mitochondria involved the use of digitonin and lubrol followed by differential centrifugation to separate soluble and particulate enzymes. Lubrol did not inhibit this enzyme. Presence of this enzyme in the mitochondrial matrix was further confirmed by western blot analysis. The results support the conclusion that L-alanine: 4,5-dioxovalerate transaminase is localized and functions in the mitochondrial matrix.


Assuntos
Rim/enzimologia , Mitocôndrias/enzimologia , Transaminases/análise , Animais , Western Blotting , Fracionamento Químico , Digitonina , Masculino , Polietilenoglicóis , Ratos , Ratos Endogâmicos , Transaminases/metabolismo
20.
Radiat Environ Biophys ; 27(3): 233-7, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3406363

RESUMO

Radon contents in some samples of tobacco, tea and tooth powder have been estimated using CR-39 solid state nuclear track detectors. The Radon content in tobacco has been found to vary from 14.06 +/- 1.4 to 89.91 +/- 3.3 mBq/l. The Radon content in tea and tooth powder has been found to vary from 27.38 +/- 1.8 to 41.81 +/- 2.2 mBq/l and 26.27 +/- 1.4 to 413 +/- 6.0 mBq/l respectively. The present investigations are useful from the health hazards point of view.


Assuntos
Dentifrícios/análise , Nicotiana/análise , Plantas Tóxicas , Radônio/análise , Chá/análise , Cremes Dentais/análise , Tecnologia Radiológica
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