Dr. Michael T. Sellix received his B.S. in Psychology with a minor in Biology from Florida State University in 1998. During his undergraduate career Dr. Sellix focused on the neurobiology of learning and memory and auditory neurophysiology. In 1998 Dr. Sellix entered the Ph.D. program in Neuroscience at Florida State University. As a graduate student Dr. Sellix worked with renowned neuroendocrinologist Dr. Marc E. Freeman, focusing on the neuroendocrine control of Prolactin secretion by dopaminergic neurons in the hypothalamus.
After receiving his Ph.D. in Neuroscience from Florida State University in 2005, Michael joined the laboratory of Dr. Gene D. Block in the Department of Biology at the University of Virginia. As a post-doctoral fellow of neuroendocrinology and reproductive medicine at UVA, Dr. Sellix had the rare opportunity to interact with several high profile chronobiologists including Dr. Ignacio Provencio, Dr. Carla Green and Dr. Herman Wijnen to name but a few. Dr. Sellix left the Block lab in 2007 and joined Prof. Michael Menaker's group wherein he focused on the role of the circadian clock in ovarian physiology.
Following four productive and exciting years in the Menaker Lab Dr. Sellix accepted a position as an Assistant Professor in the Division of Endocrinology and Metabolism at the School of Medicine.
Circadian clocks are all but ubiquitous in nature. Circadian rhythms, those biological rhythms with a period at or near 24h, are found in most, if not all, physiological systems ranging from cellular physiology and biochemistry to whole animal physiology. The mechanism controlling these oscillations is a now well-understood molecular oscillator composed of an autoregulatory transcriptional-translational feedback loop. This loop consists of interacting "clock gene" transcriptional regulators that facilitate precision through an elegant temporal scheme of positive and negative gene expression.
Our lab and others have recently determined that the circadian clock mechanism is present in the cells of the ovarian follicle. Further, we have determined that the ovary maintains an "endogenous" pattern of sensitivity to gonadotrophins that does not appear to be dependent on the timing of the LH surge or a fully developed endocrine and neuroendocrine system. These data, together with the data from other labs, suggests that the ovarian clock may play a substantial role in the timing of events in the ovary, related to both the ovulatory response to gonadotrophins and the timing of steroidogenesis.
The Sellix laboratory is currently focused on two distinct but interrelated facets of this research by asking two fundamental questions:
1) Does "clock-controlled" gene expression in the ovary, more specifically the various ovarian cell types, play a substantial role in the timing of ovarian physiology and more specifically the timing of ovulation and/or steroid hormone biosynthesis
2) Do disease states that negatively impact reproductive function (e.g. PCOS, etc.) do so by altering the timing of clock gene or clock-controlled genes in the tissues of the hypothalamo-pituitary-ovarian axis? Further, is phase-synchrony among these oscillators (or lack thereof) a contributing factor to the onset and progression of disease?
Hwang JW, Sundar IK, Yao H, Sellix MT, Rahman I. "Circadian clock function is disrupted by environmental tobacco/cigarette smoke, leading to lung inflammation and injury via a SIRT1-BMAL1 pathway." FASEB journal : official publication of the Federation of American Societies for Experimental Biology.. 2014 Jan; 28(1):176-94. Epub 2013 Sep 11.
Sundar IK, Yao H, Huang Y, Lyda E, Sime PJ, Sellix MT, Rahman I. "Serotonin and Corticosterone Rhythms in Mice Exposed to Cigarette Smoke and in Patients with COPD: Implication for COPD-Associated Neuropathogenesis." PloS one. 2014 9(2):e87999. Epub 2014 Feb 10.
Menaker M, Murphy ZC, Sellix MT. "Central control of peripheral circadian oscillators." Current opinion in neurobiology. 2013 Oct; 23(5):741-6. Epub 2013 Mar 26.
Murphy ZC, Pezuk P, Menaker M, Sellix MT. "Effects of ovarian hormones on internal circadian organization in rats." Biology of reproduction. 2013 Aug; 89(2):35. Epub 2013 Aug 15.
Sellix MT, Murphy ZC, Menaker M. "Excess androgen during puberty disrupts circadian organization in female rats." Endocrinology. 2013 Apr; 154(4):1636-47. Epub 2013 Feb 15.