Research Summary

Elucidating post-transcriptional regulation of circadian behavior in Drosophila

Evidence from genetic and molecular approaches contributed significantly to our understanding on the molecular basis of circadian timing system. Molecular oscillation of circadian clock is based on clock genes such as period and timeless that drive the rhythmic expression of transcripts and product proteins. Regulation at various levels including transcriptional, post-transcriptional and post-translational mechanisms is important for the accurate functioning of the circadian clock.  Emerging evidence indicates an important role for post-transcriptional regulation including from splicing, polyadenylation to non-coding functions by microRNAs. Among the post-transcriptional regulation, mRNA stability plays an important role in rhythmic expression and cycling of transcripts. Although microRNAs recently emerged as significant players in accurate timing of the circadian timing system, broad impact of microRNAs in circadian rhythm remains to be elucidated. To this end, my studies are focused towards elucidating micro RNA mediated post-transcriptional regulation of circadian rhythms.

Figure Legend: The molecular oscillation of circadian clock is based on cyclical expression of so-called clock genes, such as period (per) and timeless (tim). Transcription of these genes are activated during the late day to early night by transcription factors CLOCK (CLK) and CYCLE (CYC) and product proteins PER and TIM accumulate and feedback to inhibit their transcription through inactivation of CLK and CYC during the night. Studies are aimed towards elucidating the role of micro RNAs (miRNA) in post-transcriptional regulation of these clock gene transcripts.