Sabah Ul-Hasan - MS Student
46 College Road
Here in the Sower Lab, we study the neuroendocrinology of reproduction in basal vertebrates, Agnathans (jawless fish -hagfish and lamprey). Specifically, we are interested in the molecular evolution and mechanisms of hypothalamic gonadotropin-releasing hormone (GnRH), pituitary hormones, and their respective receptors.
One group of pituitary hormones is the glycoprotein hormone family. The glycoprotein hormone family includes LH, FSH, TSH, hCG, and a new member called thyrostimulin. Each glycoprotein hormone is a heterodimer comprised of one alpha (α) subunit and one beta (β) subunit. In any one species, these hormones consist of a common α subunit (GpA1) and a unique β subunit. Thyrostimulin has particularly unique subunits (GpA2 and GpB5) compared to the other glycoprotein hormones.
In contrast to Gnathostomes (jawed vertebrates), only one pituitary glycoprotein hormone (GpH) has been identified in agnathans (Sower et al. 2006; Kosugi et al unpublished; Uchida et al. 2010). The lamprey pituitary GpH is distinct and unique from all other vertebrate GpHs in that it is comprised of a GpA2 alpha subunit and a unique GpHβ beta subunit (Kosugi et al unpublished). There is evidence that lampreys also have thyrostimulin (GpA2/GpB5) but the sequence of GpB5 has not been fully elucidated.
My current and proposed work in the Sower Lab is to determine the full-length cDNA of GpB5 followed by structure-function studies of the heterodimeric thyrostimulin (GpB5/GpA2) to further our understanding of these glycoprotein hormones in vertebrate evolution.