Submission Date


Document Type

Paper- Restricted to Campus Access



Faculty Mentor

Rebecca Lyczak


Presented during the 22nd Annual Summer Fellows Symposium, July 24, 2020 at Ursinus College.

A related presentation is available here.

Project Description

In order to develop into mature organisms, fertilized embryos must go through growth, DNA replication, and cell division. These phases together make up the cell cycle, and movement through the phases is facilitated by many proteins. In the model organism Caenorhabditis. elegans, one of these proteins is PAM-1, a cytosolic puromycin-sensitive aminopeptidase that plays an essential role in developmental processes, like the cell cycle. PAM-1 acts by regulating proteins necessary for the cell to progress out of mitosis. It also plays a role in the establishment of the anteroposterior axis, which is required for the organism to develop correctly. When the PAM-1 protein is not functioning properly, embryos exhibit polarity defects and do not survive. Additionally, it is suspected that PAM-1 interacts with a protein called WEE-1.3, as a depletion of PAM-1 is lethal, but a simultaneous depletion of WEE-1.3 increases the rate of hatched embryos. WEE-1.3 too is a cell cycle regulator and acts to prevent the premature activation of factors that cause the maturation of oocytes. The mechanism of the interaction between these two proteins has yet to be fully understood. One theory suggests PAM-1 regulates levels of WEE-1.3 through degradation, but preliminary data showed no statistical significance between WEE-1.3 levels in the presence or absence of PAM-1. Hypotheses yet to be tested consider the involvement of other proteins in the network that are regulated by PAM-1 and WEE-1.3. Testing these hypotheses may help us better understand proteins regulating the cell cycle.


Available to Ursinus community only.