Fluorescent tissue imageRamaley N384
Department of Integrative Physiology
University of Colorado
Boulder, CO 80309-0354
phone: 303-735-4364

Research Interests

  • The Reproductive Endocrinology Laboratory is interested in understanding how hormones from the brain and pituitary control puberty, male and female reproduction, and reproductive senescence. We are particularly interested in the function of gonadotropin-releasing hormone (GnRH) and the developmental regulation of neurons that produce GnRH, since developmental abnormalities in these neurons lead to absent puberty and infertility in all vertebrates including humans. Additional projects include investigating (1) the evolutionary pattern of GnRH using molluscan models, and (2) the developmental regulation of the endocrine hypothalamus.


  • Laboratory Director: Pei-San Tsai, Ph.D.
  • Professional Research Assistant: Kelsey Sanders, B.A.
  • Graduate Students: Tyler Akonom, M.S., Nate Anderson, B.A., Katelyn Jewell, B.A.
  • Undergraduate Students: Grace Clarke, Schasny Osteroo, Natalie Shelden, Alex Strauss
  • Collaborators: Seth Finklestein, M.D., Stemetix Inc.; Dan Medeiros, Ph.D., University of Colorado Boulder; Nelly Pitteloud, M.D., University of Lausanne; Stacia Sower, Ph.D., University of New Hampshire at Durham.

Tsai lab personnel 2018

From left to right. Front row: Rebecca Bolen, Cassie Horton, Pei-San Tsai, Cynthia Dela Cruz, Michaela Deck.
Second row: Anthony Martillotti, Nate Anderson, Tyler Akonom, Samantha Bonelli, Amanda Brown, Phaivit Laphyai, Hugh Zhang.

Current Research Projects

  • Development and maintenance of the reproductive brain.
  • Functional and structural evolution of gonadotropin-releasing hormone superfamily.
  • Etiology of infertility in humans.
  • Embryonic development of the neuroendocrine hypothalamus.

Opportunities for Undergraduates

  • The requirements for undergraduate students who want a research experience in our Laboratory are:
    • Junior or senior status.
    • Minimum commitment of one year.
    • Be able to work at least 8 hours per week.
    • Either have completed or be concurrently enrolled in IPHY 3410 (Human Anatomy) or IPHY 3470/3480 (Human Physiology).
    • Participate in UROP or enroll in independent study (IPHY 4860).
    • Minimum GPA of 3.2.
  • For more information, contact Prof. Pei-san Tsai (pei-san.tsai@colorado.edu).

Recent Publications

  • Kavanaugh SI, Tsai P-S. Functional authentication of a novel gastropod gonadotropin-releasing hormone receptor reveals unusual features and evolutionary insight. PLoS One 11: e0160292, 2016.
  • Martillotti AW, Tsai P-S. An adipokinetic hormone acts as a volume regulator in the intertidal gastropod mollusk, Aplysia californica. Frontiers in Endocrinology 9: 493, 1-10, 2018
  • Miller AV, Kavanaugh SI, Tsai P-S. Disruption of the suprachiasmatic nucleus in fibroblast growth factor signaling-deficient mice. Fronters in Endocrinology 7: 11, 1-8, 2016.
  • Plachetzki DC, Tsai P-S, Kavanaugh SI, Sower SA. Ancient origins of metazoan gonadotropin-releasing hormone and their receptors revealed by phylogenomic analyses.General and Comparative Endocrinology 234: 10-19, 2016.
  • Tsai P-S. Gonadotropin-releasing hormone by any other name would smell as sweet. General and Comparative Endocrinology 264: 58-63, 2018.


  • 2014-2019, NSF, "Multifunctional Nature of Protostomian GnRH-like Molecules"
  • 2016-2021, NIH, "Postnatal Plasticity in the GnRH System"