Estudo da interação entre a via genética do microRNA156/squamosa promoter-binding protein-like e brassinosteróides durante o desenvolvimento de Arabidopsis thaliana

• Ano de defesa: 2015
• Autor(a) principal: Rojas, Carlos Hernán Barrera [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Genetica vegetal; Expressão gênica; Genetica molecular; Plantas; Molecular genetics
• Link de acesso: http://hdl.handle.net/11449/128123

Plant development is affected by different factors such as micro-RNAs (miRNAs) and phytohormones which interact in a complex regulation network. Among miRNAS, miRNA156 (miR156) regulates SQUAMOSA Promoter- Binding Protein-Like (SPL) transcription factor family affecting different plant development processes. Among phytohormones, brassinosteroids (BRs) participate in regulation of vegetal juvenile processes. miR156/SPL-BRs interaction is unknown whereby the aim of this work was to evaluate the interaction between those two pathways during Arabidopsis thaliana juvenile development. Main root (RP), lateral root number (RL) and hypocotyl length were selected as markers of this interaction. A. thaliana (Col-0 ecotype) overexpressing miR156 (miR156-OE), plants with miR156 reduced activity (Mimicry-156) and wild type (WT) plants were used. 24-Epibrassinolide (24- EBL), the most active BRs, was selected. miR156-OE plants have longer RP length, more RL and 24-EBL sensitivity. Opossite phenotypes were observed on Mimicry-156 plants. Besides, miR156-OE plants have longer hypocotyl length while Mimicry-156 plants have shorter. SPLs genes, SPL2, -3, -4, -5, and -6 responded to 24-EBL treatment. BRs pathway genes, CPD, BZR1, BES1 and BAS1 had changes in gene expression. Our data suggest a interaction between the miR156/SPL and BRs pathways and help to understand the molecular genetics of Arabidopsis development