Regulatory mechanisms of lateral plant organ growth

• Grant number: 15/05758-4
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2015
• End date: November 30, 2015
• Field of knowledge: Biological Sciences - Botany - Pant Physiology
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Marcelo Carnier Dornelas
• Grantee: Diego Ismael Rocha
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

The final shape and size of a plant organ is determined by the coordination between two basic cellular processes: cell expansion and division. Genetic analysis in Arabidopsis thaliana has revealed regulatory genes that control specific aspects of organ growth. For example, the transcription factor JAGGED (JAG) controls growth in the distal region of shoot organs, while the transcription regulators GRF/AN3 appears to control growth mostly in the basal region. The gene networks controlled by JAG and GRF/AN3 have been studied, but much less is known about how these pathways interact to shape shoot organs. Recent experiments indicate that the JAG protein directly binds to multiple genes at the core of the GRF/AN3 network, including several GRF genes, AN3, a gene encoding a microRNA (miRNA396) that cleaves GRF and it is activated by TCPs. These results suggest that growth of the distal and basal regions of plant organs is promoted by mutually antagonistic genetic pathways. The characterization of gene interactions among GRFs, TCPs and JAG, at the cellular and molecular levels will add knowledge in better understanding of the role of these genes in establishing the size and shape of plant organs, bringing up new perspectives on the biological role of them in plants. (AU)