Tropomodulin 1 Regulation of Actin Is Required for the Formation of Large Paddle Protrusions Between Mature Lens Fiber Cells.

Purpose: To elucidate the proteins required for specialized small interlocking protrusions and large paddle domains at lens fiber cell tricellular junctions (vertices), we developed a novel method to immunostain single lens fibers and studied changes in cell morphology due to loss of tropomodulin 1 (Tmod1), an F-actin pointed end-capping protein.

Methods: We investigated F-actin and F-actin-binding protein localization in interdigitations of Tmod1+/+ and Tmod1-/- single mature lens fibers.

Results: F-actin-rich small protrusions and large paddles were present along cell vertices of Tmod1+/+ mature fibers.

Lacrimal Gland Inflammation Deregulates Extracellular Matrix Remodeling and Alters Molecular Signature of Epithelial Stem/Progenitor Cells.

Purpose: The adult lacrimal gland (LG) is highly regenerative and is able to repair itself even after substantial damage; however, this ability to regenerate is lost with the development of dry eye conditions in chronically inflamed LGs.This study compares changes in the cell adhesion and cell matrix molecules and stem cell transcription factors in the LGs of healthy mice and of two mouse models of Sjögren's syndrome: nonobese diabetic (NOD) and MRL-lpr/lpr (MRL/lpr) mice during the early stage of inflammation.

Methods: The LGs from 12- to 13-week-old female MRL/lpr and male NOD mice along with their respective control strains were harvested and divided into three pieces and processed for quantitative (q) RT-PCR and qRT-PCR Arrays, histology, immunohistochemistry, and Western blotting.