Determination of the Role of Cofilin1 in Rod Photoreceptors

Seth Hubbard, Meredith Hubbard, Alecia Gross, Department of Neurobiology, University of Alabama at Birmingham, 1825 University Boulevard, Shelby 931, Birmingham, AL 35294

Nuclear distribution protein C (NUDC) has previously been shown to modulate F-actin dynamics through cofilin1 (CFL1), an important F-actin severing protein. Recently, we demonstrated a role for NUDC in the development and maintenance of rod photoreceptors through transgenic shRNA knockdown of NudC in X. laevis tadpoles. Additionally, we have recently discovered that CFL1 localizes to the inner segments of photoreceptors and is close to NUDC in these cells. Interestingly, we found that rod cells with decreased NUDC levels showed elongated outer segment (OS) disks, increased F-actin, and reduced levels of CFL1. Although the role of CFL1 in actin regulation has been described in other cell types, it is unknown what role it plays specifically in photoreceptors. Here, we seek to investigate the molecular mechanisms governing F-actin architecture by generating transgenic X. laevis expressing WT CFL1 (CFL1), constitutively active phospho-null CFL1 (CFL1S3A), and dominant-negative phospho-mimic CFL1 (CFL1S3D) in rods. Localization of each of these proteins will be shown through immunohistochemistry (IHC) and fluorescence confocal imaging, and rod cell ultrastructure will be examined with transmission electron microscopy (TEM). We hypothesize we will see altered OS disk ultrastructure in both the phospho-mimic and phospho-null mutants of CFL1.

Additional Abstract Information

Presenter: Seth Hubbard

Institution: University of Alabama at Birmingham

Type: Poster

Subject: Biology

Status: Approved

Time and Location

Session: Poster 2
Date/Time: Mon 3:00pm-4:00pm
Session Number: 2615