Faculty

Dr. Joseph S. Tash is Director of the Interdisciplinary Center for Male Contraceptive Research and Drug Development.  Dr. Tash received his Ph.D. (Cantab) in Reproductive Biology from University of Cambridge under the mentorship of Professor Thaddeus R.R. Mann, FRS, OBE, and was a post-doctoral fellow in the laboratory of Anthony R. Means at Baylor College of Medicine.  His research interests have focused on male reproductive biology from the start, and include basic regulation of sperm motility and sperm function, and identification of testis and/or sperm specific components that can be targeted for development of reversible non-hormonal male contraceptive agents. Dr. Tash’s U54 project is focusing on continued drug development and elucidating the mechanism of action of gamendazole, an orally active highly potent anti-spermatogenic contraceptive agent [1, 2]. The project is also discovering alternative chemical scaffold lead agents that target the same Sertoli cell molecular targets as gamendazole.

The Interdisciplinary Center for Male Contraceptive Research and Drug Development (PI, Dr. Tash), along with ongoing contract work (PI, Dr. Gunda Georg) under the auspices of the Contraceptive and Reproductive Health Branch of NICHD, represents a multi-university effort to develop reversible non-hormonal male contraceptive agents. The U54 center projects are supported by an Administrative Core (Barb Shull, Administrative Assistant), an Imaging Core, and a Drug Discovery and Synthesis Core (including medicinal chemistry and synthesis up to cGMP standards, high throughput screening (assay development, protein expression and purification, and library screening), x-ray crystallography, and rational drug design expertise).  Additional details of the center projects and cores and their key personnel are found via the links on this web site.

1.  Tash JS, Attardi B, Hild SA, Chakrasali R, Jakkaraj SR, Georg GI. A novel potent indazole carboxylic acid derivative blocks spermatogenesis in rats after a single oral dose and Is contraceptive. Biol.Reprod. 2008; 78: 1127-1138.

2.  Tash JS, Chakrasali R, Jakkaraj SR, Hughes J, Smith SK, Hornbacker K, Lushington GH, Heckert LL, Blagg BSJ, Georg GI. Gamendazole, an orally active indazole carboxylic acid male contraceptive agent, targets HSP90AB1 (HSP90BETA) and EEF1A1 (eEF1A), and stimulates Il1a transcription in rat Sertoli cells. Biol. Reprod. 2008; 78: 1139-1152.