Study of interfering factors in development and final size of plants female reproductive organ

• Grant number: 11/51844-9
• Support Opportunities: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): March 01, 2012
• Effective date (End): February 28, 2014
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Maria Helena de Souza Goldman
• Grantee: Hebréia Oliveira Almeida Souza
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

This project intends to study the molecular mechanisms through which the hormone auxin and the proteins SCI1 (Stigma/style Cell-cycle Inhibitor 1) and TOB092H06 influence cell division and expansion, regulating the development and the final size of the female reproductive organ (pistil). Therefore, the objectives of this project are: 1) To study the effects of decreased auxin levels in pistil development: a. To produce N. tabacum transgenic plants with decreased pistil auxin levels, through the expression of the iaaL gene of Agrobacterium tumefaciens, under the control of ST1G1, a stigma-specific promoter; b. To analyze the phenotype of transgenic plants comparing them with the wild-type (SR1), mainly concerning pistil morphology and reproductive parameters; c. Perform the separation by two-dimensional electrophoresis of pistil protein extracts of STIG1::iaaL transgenic and SR1 control plants and analyze the differentially expressed proteins, which will be identified by MALDI-TOF. 2) To characterize the SCI1 protein: a. To express the recombinant SCI1 in E. coli; b. To produce antibody against the recombinant SCI1 protein; c. To compare the phosphorylated residues of SCI1 extracted from leaves and pistils of 35S::GFP-SCI1 transgenic plants. 3) To study interactions between SCI1 and proteins that interfere with cell division: a. To test the interaction by two-hybrid between cyclin L and cyclin-related with the CDKG;2 cyclin-dependent kinase; b. If the proteins interact to test the activity of CDKG;2 on histones and/or other possible substrate of CDK; c. If a and b are positive to test the inhibition of CDKG activity by SCI1. 4) To study the protein encoded by the clone TOB092H06 and its role on pistil development: a. To express the 092H06 recombinant protein in an heterologous system, as E. coli; b. To produce antibodies against the 092H06 recombinant protein; c. To quantify the 092H06 protein in transgenic and control plants. (AU)