RESUMO
A cDNA-AFLP approach was used to identify transcript and/or genes specifically expressed in response to drought in tea. Drought was artificially induced and whole genome transcript profiling was done at three different stages-6 days before wilting, 3 days before wilting and at wilting stage of both tolerant and susceptible cultivars, and genetic differences was thus visualized as polymorphisms in the transcriptome. The cDNA-AFLP technique allowed genes and transcripts to be identified in the tolerant genotype (TV-23) whose expression is responsive to drought stress. The cluster analysis revealed two types of clustering-type I separated the tolerant and susceptible cultivar, whereas type II separated the time point of sample and this may be grouped as early and late responsive transcripts. 108 transcript derived fragments were identified as differentially expressed in tolerant genotypes of which 89 sequences could be obtained. Fifty-nine of them showed homology in the public databases. Functional ontology showed genes related to carbohydrate metabolism, response to stress, protein modification process and translation. Cluster I includes five fragments and cluster II includes 25 fragments. Other genes strongly expressed in response to drought in tolerant genotype would help us in identifying and determining the genetic basis of mechanisms involved in conferring drought tolerance in tea.
Assuntos
Secas , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Chá/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Análise por Conglomerados , Fragmentação do DNA , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Genótipo , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , RNA de Plantas/genética , RNA de Plantas/isolamento & purificação , TranscriptomaRESUMO
Understanding the genes that govern tea plant (Camellia sinensis) architecture and response to drought stress is urgently needed to enhance breeding in tea with improved water use efficiency. Field drought is a slow mechanism and the plants go through an adaptive process in contrast to the drastic changes of rapid dehydration in case of controlled experiments. We identified a set of drought responsive genes under controlled condition using SSH, and validated the identified genes and their pattern of expression under field drought condition. The study was at three stages of water deficit stress viz., before wilting, wilting and recovery, which revealed a set of genes with higher expression at before wilting stage including dehydrin, abscissic acid ripening protein, glutathione peroxidase, cinnamoyl CoA reductase, calmodulin binding protein. The higher expression of these genes was related with increase tolerance character of DT/TS-463 before wilting, these five tolerant progenies could withstand drought stress and thus are candidates for breeding. We observed that physiological parameter like water use efficiency formed a close group with genes such as calmodulin related, DRM3, hexose transporter, hydrogen peroxide induced protein, ACC oxidase, lipase, ethylene responsive transcription factor and diaminopimelate decarboxylase, during wilting point. Our data provides valuable information for the gene components and the dynamics of gene expression in second and third leaf against drought stress in tea, which could be regarded as candidate targets potentially associated with drought tolerance. We propose that the identified five tolerant progenies on the basis of their drought tolerance can thus be utilised for future breeding programmes.
Assuntos
Adaptação Biológica , Camellia sinensis/genética , Secas , Perfilação da Expressão Gênica/métodos , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Camellia sinensis/enzimologia , Camellia sinensis/fisiologia , Biologia Computacional/métodos , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genes de Plantas , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Lipase/genética , Lipase/metabolismo , Doenças das Plantas/genética , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análise de Componente Principal , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Água/metabolismoRESUMO
Renal disease has become increasingly more prevalent in our society. There are many more people undergoing dialysis treatment and kidney transplants than there were only a decade ago. The dental care of these patients can be complex, given the medications associated with the disease and the medical conditions that result from inadequately functioning kidneys. This article reviews the literature regarding the dental management of patients with acute and chronic renal failure.