学术活动
学术活动

植物科学前沿系列讲座

2017-10-20

 

Title: Environmental perception and epigenetic memory in plants: insights from FLC.

Speaker: Dr. Julia Questa, John Innes Center

Time: 10:00 am

Day/Date: Oct 20th, 2017 (Friday)

Host PI: Prof. Rosa Lozano-Duran

Venue: PSC Auditorium

 Abstract:

Throughout my research career I have been interested in how environment-driven chromatin modifications impact gene expression and modulate plant development. My PhD project focused on how UV-B radiation releases the epigenetic silencing of Mutator DNA transposons in maize. During my postdoc, I investigated how perception of the cold temperatures of winter is translated into epigenetic silencing programs to promote the floral transition in Arabidopsis. I focused on the role of Polycomb Repressive Complex 2 (PRC2) and the long non-coding RNA (lncRNA) COOLAIR in epigenetic silencing of the floral repressor FLOWERING LOCUS C (FLC) during vernalization, the acceleration of flowering by exposure to prolonged cold. The identification of the transcriptional repressor VAL1 as a key component of the vernalization mechanism has provided a significant advance to the field. VAL1 marks the PRC2 entry site at FLC chromatin triggering epigenetic silencing. Furthermore, my work also determined that COOLAIR facilitates cold-induced FLC transcriptional silencing by coordinating the switch between active and repressive chromatin states. More recently, I have been able to show that natural allelic variation at FLC influences the rate of epigenetic silencing of the gene. These results suggest that modulation of chromatin-based mechanisms is likely to be involved in adaptation to changing environments.