RESUMO
BACKGROUND: The root apical meristem of crop and model legume Medicago truncatula is a significantly different stem cell system to that of the widely studied model plant species Arabidopsis thaliana. In this study we used the Affymetrix Medicago GeneChip(R) to compare the transcriptomes of meristem and non-meristematic root to identify root meristem specific candidate genes. RESULTS: Using mRNA from root meristem and non-meristem we were able to identify 324 and 363 transcripts differentially expressed from the two regions. With bioinformatics tools developed to functionally annotate the Medicago genome array we could identify significant changes in metabolism, signalling and the differentially expression of 55 transcription factors in meristematic and non-meristematic roots. CONCLUSION: This is the first comprehensive analysis of M. truncatula root meristem cells using this genome array. This data will facilitate the mapping of regulatory and metabolic networks involved in the open root meristem of M. truncatula and provides candidates for functional analysis.
Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Medicago truncatula/genética , Meristema/genética , Transcrição Gênica/genética , Metabolismo dos Carboidratos/genética , Comunicação Celular/genética , Parede Celular/genética , Parede Celular/metabolismo , Flavonoides/metabolismo , Genes de Plantas/genética , Genoma de Planta , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição/genéticaRESUMO
Quantitative proteome analyses of meristematic and nonmeristematic tissues from Medicago truncatula primary and lateral roots and meristem tissues from plants treated with acetohydroxyacid synthase-inhibiting herbicides were made. The accumulation of 81 protein spots changed in meristematic and nonmeristematic tissues and 51 protein spots showed significant changes in accumulation in herbicide-treated meristems. Identified proteins indicate two trends, (i) increased accumulation of cell division and redox-mediating proteins in meristems compared to nonmeristematic tissues and (ii) increased accumulation of pathogenesis-related and decreased accumulation of metabolic proteins in herbicide-treated roots.
