Functional analysis of the role of the Arabidopsis NAC transcription factor JUNGBRUNNEN1 (JUB1) in GA and BR signalling

• Applicant: Professorin Dr. Salma Balazadeh
• Subject Area: Plant Physiology ; Plant Genetics and Genomics
• Term: from 2013 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 243809434

Hormones play crucial roles in regulating plant growth, development and defence responses. The biosynthetic pathways for plant hormones have been largely elucidated; however, the mechanisms by which hormone levels are regulated are still poorly understood. Our group studies the function of transcription factors (TFs), particularly those regulating plant growth and stress responses. One of the TFs analysed is JUNGBRUNNEN1 (JUB1), a NAC transcription factor. Overexpression of JUB1 in Arabidopsis thaliana strongly extends longevity and confers tolerance to various abiotic stresses in part by dampening the cellular H2O2 level. Beside the extended life span, JUB1 overexpressors show typical phenotypes of GA (gibberellic acid)- and BR (brassinosteroid)-biosynthesis and perception mutants. Experimental evidence suggests that JUB1 plays a central role in the regulation of plant growth and stress responses through direct transcriptional repression of both, GA and BR biosynthesis genes. The goal of the project therefore is to unravel the molecular mechanisms by which JUB1 controls GA and BR biosynthesis/signalling pathways. The discoveries will also pave the way for a better understanding of the functions of JUB1 in regulating plant growth.

• DFG Programme: Research Grants