Investigating Protein Interactions Between PAM-1, CDC-25.1, and MBK-2 During Oocyte Maturation in C. elegans

Ilyssa Marsh

OAI: oai:digitalcommons.ursinus.edu:biology_sum-1162

Caenorhabditis elegans are transparent nematodes often used as model organisms. Their fully sequenced genome, simple organ systems, and high fecundity make them ideal for studying protein interactions. PAM-1 is a puromycin sensitive aminopeptidase that acts as a cell cycle regulating protein. Specifically, PAM-1 regulates oocyte maturation and polarity establishment. Mutations in the pam-1 gene cause infertility, defects in polarity establishment, and abnormal progressions of meiosis and mitosis. The mechanisms through which these phenotypes are produced remain unclear. PAM-1 is of interest because puromycin sensitive aminopeptidases are highly conserved across the animal phylum, but how they function remains unclear. In humans, PAM-1 is homologous to a puromycin sensitive aminopeptidase called the NPEPPS protein. This protein is believed to play a protective role in neurological diseases such as Alzheimer's disease. This summer I have been investigating protein interactions between PAM-1 and other proteins involved in oocyte maturation and embryogenesis in wildtype worms and pam-1 mutants via RNA interference and Western blots. Two specific proteins I am investigating are CDC-25.1 and MBK-2. CDC-25.1 dephosphorylates the maturating promoting factor in C. elegans oocytes, allowing oocytes to mature and become fertilized. Phosphorylation of the Minibrain kinase 2 (MBK-2), homologous to human dual-specificity tyrosine phosphorylation kinase 2 (DYRK2), is required for proper meiotic cell cycle progression in C. elegans. I am interested in investigating whether PAM-1 interacts with either of these proteins. If so, this would propose an explanation as to why the phenotypes seen in pam-1 mutants are observed.

C. elegans oocyte maturation pam-1 CDC-25.1 MBK-2 Biology developmental biology Genetics Life Sciences