Análise do transcriptoma de arroz de terras altas (Oryza sativa L.) cultivado sob condição de seca

• Autor(a) principal: Silveira, Ricardo Diógenes Dias
• Data de Publicação: 2014
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000002q8d
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4548
• topic: Expressão diferencial de genes; Estresse hídrico; Anotação funcional; Cultivares brasileiras de arroz; Differential gene expression; Water deficit; Functional annotation; Brazilian rice cultivars; GENETICA::GENETICA MOLECULAR E DE MICROORGANISMOS

The upland rice is sensitive to drought especially during the reproductive phase, when even moderate stress can result in drastic reduction in yield. Upon the occurrence of the drought a variety of genes is induced in plants, triggering a complex network of responses that extends from the perception and recognition of sign of stress, through activation of adaptive response genes. The objective of this thesis was to study the transcriptome of two Brazilian cultivars of upland rice (Douradão and Primavera) contrasting in relation to drought tolerance, and subjected to two experiments under water deficit in two consecutive years. In the first year, corresponding to Article 1, the transcripts from leaf samples were sequenced by RNA-seq, and in the second year, corresponding to Article 2, the transcripts from leaf and root samples were sequenced, for both cultivars, under normal and limited irrigation during the reproductive phase. In Article 1, the sequencing showed in Douradão 27,618 transcripts, from which 24,090 (87.2 %) showed homology to rice genes and 27,221 transcripts in Primavera, from which 23,663 (86.9 %) showed homology to rice genes. Douradão had 493 diferentially expressed genes (DEGs) and Primavera 1,154 DGEs. In Article 2 it were identified 44,978 and 37,898 transcripts in leaf and root tissues, respectively. Douradão showed 3,554 and 840 diferentially expressed genes (DEGs), in leaf and root tissues, respectively, while Primavera showed 1,141 and 1,975 DEGs on those tissues, respectively.It were identified genes from different metabolic routes related to distinct drought tolerance mechanisms in leaf and root tissues, such as cell signaling -related genes, transcription factors, functional protective proteins and cell cellular detoxification enzymes. A set of expressed genes from both tissues were validated by RT–qPCR and most of them were similar to the results of RNA-seq results. The rice transcripts not annotated were submitted to an orthology analysis in relation to the Arabidopsis thaliana databank, which revealed one gene related to the root cell growth Douradão. The 16 genes validated by RT-qPCR will be used as molecular markers for marker assisted selection in the upland rice breeding program and are candidate genes for use in transformation of rice cultivars susceptible to drought.