The Maine Lab

Welcome to the Maine lab in the Department of Biology at Syracuse University.  We study the regulation of cell fate during animal development, focusing on germline development in the nematode, Caenorhabditis elegans.  We use a variety of genetic, molecular, and cell biological approaches to study mechanisms that regulate germ cell proliferation and gamete formation.

Current areas of research include:

• Regulation of chromatin structure during meiosis
Development of a functional germ line relies on tissue-specific modes of gene regulation.  During meiosis in animals and fungi, the expression of genes on unpaired (unsynapsed) chromosomes and chromosomal regions is repressed.  This broadly conserved phenomenon may be important for genome defense, maintenance of genome integrity, and/or segregation of unpaired chromosomes, as well as germline development.  In C. elegans, meiotic silencing occurs at the chromatin level via accumulation of histone "silencing" modifications. We have shown that chromatin regulation in the germline involves RNA-directed RNA polymerases (RdRPs), suggesting that non-coding RNAs also participate in the process. We are currently identifying additional factors that regulate meiotic chromatin structure. Read more

• Inductive cell-signaling in the gonad
The C. elegans gonad contains a population of mitotic germ cells that give rise to gametes throughout the adult life of the animal.  Germ cells receive an inductive signal from the somatic gonad, mediated by the conserved Notch-type signaling pathway, which is essential for proliferation. Notch-type signaling is widely used to regulate cell proliferation and/or differentiation in diverse animal species.  We are interested in understanding how Notch-type signaling is regulated in the developing and adult C. elegans gonad.  Read more

• Maintaining the balance between proliferation and differentiation
While germline proliferation depends on inductive Notch-type signaling from the somatic gonad, additional factors act in parallel to promote germline proliferation.  Cells must escape these proliferative controls in order to exit mitosis, enter meiosis, and form gametes. Moreover, entry into meiosis requires the GLD-1 and GLD-2, two proteins that redundantly to promote germ cell entry into meiosis and/or to inhibit proliferation.    Read more