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?
Mereness AL, Murphy ZC, Sellix MT. "Developmental programming by androgen affects the circadian timing system in female mice." Biology of reproduction. 2015 Apr; 92(4):88. Epub 2015 Feb 18.
Sellix MT. "Circadian clock function in the mammalian ovary." Journal of biological rhythms. 2015 Feb; 30(1):7-19. Epub 2014 Nov 03.
2014 Oct 21
van der Vinne V, Riede SJ, Gorter JA, Eijer WG, Sellix MT, Menaker M, Daan S, Pilorz V, Hut RA. "Cold and hunger induce diurnality in a nocturnal mammal." Proceedings of the National Academy of Sciences of the United States of America. 2014 Oct 21; 111(42):15256-60. Epub 2014 Oct 06.
Amaral FG, Castrucci AM, Cipolla-Neto J, Poletini MO, Mendez N, Richter HG, Sellix MT. "Environmental control of biological rhythms: effects on development, fertility and metabolism." Journal of neuroendocrinology. 2014 Sep; 26(9):603-12.
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.