Understanding the role of the MUT9 kinases in flowering time regulation in Arabidopsis thaliana

• Grant number: 13/01484-1
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): July 01, 2013
• Effective date (End): June 30, 2015
• Field of knowledge: Biological Sciences - Genetics - Plant Genetics
• Principal Investigator: Juan Armando Casas Mollano
• Grantee: Izabel Cristina Ribeira de Moraes
• Home Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The correct timing of flowering is critical for the success of plant propagation. Environmental, developmental, and physiological cues provide essential signals that direct the plant into the flowering decision. One important mechanism by which flowering time key genes are regulated is established at the chromatin level, with specific histone posttranslational modifications underlying repressive and active chromatin states. The histone H3 threonine-3 (H3T3) is phosphorylated by the MUT9 kinase and plays a role in gene silencing in Chlamydomonas reinhardtii. In higher plants, homologs of the MUT9 kinase form a plant-specific gene family of which nothing is known. Mutants on the Arabidopsis MUT9 genes, At3g13670 and At2g25760, display differences in flowering time when compared to the wild type, indicating that these genes are involved in the regulation of flowering. Hence, this proposal aims to investigate their role in the control of flowering time in A. thaliana. First, spatial and temporal expression of these genes will be studied by using promoter-gene reporter fusions and translational fusions with the green fluorescent protein (GFP). The kinase activity of At3g13670 and At2g25760 proteins on histone substrates will also be investigated. Second, to identify the flowering pathways and target genes of At3g13670 and At2g25760, flowering time of wild type and the mutants under different conditions and the expression of key flowering regulatory genes will be analyzed. Finally, Histone phosphorylation and other modifications will be studied on the identified targets. This project is expected to greatly increase our understanding of a novel component participating of flowering time control in higher plants.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MORAES, IZABEL; YUAN, ZUO-FEI; LIU, SHICHONG; SOUZA, GLAUCIA MENDES; GARCIA, BENJAMIN A.; ARMANDO CASAS-MOLLANO, J. Analysis of Histones H3 and H4 Reveals Novel and Conserved Post-Translational Modifications in Sugarcane. PLoS One, v. 10, n. 7 JUL 30 2015. Web of Science Citations: 7.