A Conversation with Caroline Dean.

Dr. Dean: My lab works on how plants know when to flower, so I got into this wonderful world of chromatin and RNA through quite an unintentional route. Many years ago I went back to the U.K., having been a postdoc in the U.S., and decided seasonal timing was really interesting. The place I live in—Norwich—has fairly distinct winters and in spring we have this wonderful bloom. The question is, how is flowering so synchronized? My lab decided to study the molecular control of flowering, focusing on how plants decide whether to overwinter before flowering, and how they perceive winter. The many genetic routes we used to study these questions led us into the study of one gene. It’s a gene that encodes a repressor of flowering. To be able to flower, the plant switches that gene off through a cold-induced Polycomb switching mechanism. As we dissected this mechanism, we came across a set of antisense transcripts at the repressor locus so we have spent time dissecting how regulatory RNAs affect the chromatin environment of the locus, which affects the transcriptional output, which then affects whether the plants actually need winter and whether they can respond to winter.