The rotation of the earth creates a daily fluctuation of environmental cues and organisms have evolved internal timing systems, called circadian clocks, to coordinate their daily activities to anticipate and prepare for these environmental changes. The principal circadian pacemaker is located in the suprachiasmatic nucleus (SCN) of the hypothalamus in mammals, and SCN regulates many physiological processes, such as hormone secretion, neuronal activity, physical condition, body temperature, and most obviously sleep. Our goal is to understand how the clock machinery controls circadian biochemistry, physiology, and ultimately behavior at a molecular level. Photo Source: Allan Ajifo (CC BY 2.0)
In order to maintain daily cycles, the circadian clock must tightly regulate the rhythms of thousands of mRNAs and proteins with the correct period, phase, and amplitude to ultimately drive the wide range of rhythmic biological processes. Recent genomic approaches, however, have revealed that in many cases protein synthesis rhythms are uncoupled from mRNA rhythms, suggesting post-transcriptional regulatory mechanisms play important roles in driving circadian rhythmicity. Even after transcripts are made from DNA, subsequent processing and regulatory steps determine when, where, and how much protein will be generated, and we aim to unravel how post-transcriptional processes contribute to shape rhythmic protein expression patterns, independent of transcriptional control. Photo Source: Col Ford and Natasha de Vere (CC BY 2.0)
Poly(A) tails are hallmarks of most eukaryotic mRNAs found in the 3’-end of mRNAs, and this mRNA structure is conserved from bacteria to humans. Functions of poly(A) tails are thought to protect mRNAs from degradation and promote translation initiation, although this has not been adequately addressed due to technical challenges. Using recently developed genomic technologies that have enabled us to analyze actual sequence and length of poly(A) tails, we attempt to solve the mysteries of poly(A) tails; How long do they need to be? Are functions of poly(A) tails different between organisms? Answers to these questions will also provide profound insights into how each organism evolved by adding flexibility to non-DNA-encoded structures.
|Dorjsuren Battogtokh||Visiting Scholar|
|Kevin He||Visiting Student|
|Benjamin Unruh||Visiting Student|
|Chuanli Zhou||Visiting Student|