Shadia Hamideh, Post 1

Greetings fellow science nerds and lab rats :)

I’m Shadia Hamideh and I am a rising senior majoring in MCDB. For the summer, I am at The Scripps Research Institute in beautiful La Jolla, California. I work in Dr. Velia Fowler’s lab on cataracts and the role of actin binding proteins in lens function.  It is known that actin binding proteins work synergistically with other cytoskeleton proteins to maintain lens structure, transparency, and fluidity. Different actin binding proteins are exclusively expressed in different cell types in the lens. The lab has previously focused on the actin binding protein that is expressed in the lens fiber. My project is to continue to study actin binding proteins by focusing on the actin binding protein that is exclusively expressed in the lens epithelial cells. A couple months ago, my mentor stained cryosections of a mouse lens and noticed that the epithelial cell specific actin binding protein localized near the nucleus in star-like structures; each epithelial cell had one starlike structure which was always near the nucleus.

            Broadly, my project is to understand the role of the epithelial specific actin binding protein in the lens. I began by isolating lens epithelial cells from mouse lenses by peeling off the lens capsule. These epithelial cells were grown in the presence or absence of an inhibitor. TGF-Beta inhibitor is known to make primary cell culture lens epithelial cells cuboidal in vitro. We wanted to study the differences in the actin cytoskeleton that facilitate the cuboidal shape of epithelial cells before they differentiate into lens fiber cells.

            After two weeks of analyzing 100X images of my cells, I was able to identify the same structures that my mentor found in her cryo sections of the lens. The first image is a cell that is untreated and the second image is a cell that is treated with TGF-Beta inhibitor. We noticed that the cells that have these star-like structures have a different morphology : the actin is unorganized, they seldom have stress fibers, clusters are near the nuclei in regions where actin is not , and these structures reside in polynucleated cells.

Current questions are: what are these polynucleated cells doing and how do these clusters contribute to epithelial cell structure.

Side note: everyone wears sandals to lab— it’s a San Diego thing, I guess. And sometimes I find surfboards casually lying outside of lab. My SURF cohort is pretty cool, there’s people from all over the country and there's a handful from Central America. We recently went to Disneyland together and this weekend we’re going to Catalina Island— they're an ambitious group and I just want to sleep in on the weekends.

Side Note II: My lab is somewhat proprietary and at the moment I am unable to disclose the names of the proteins we are studying.

WT Primary Cell Plate 1 Untreated Day 15

WT Primary Cell 1 uM TGF-B Inhibitor  Plate 1 Day 15