Chauss, Daniel C.

Relationships
Member of: Graduate College
Person Preferred Name
Chauss, Daniel C.
Model
Digital Document
Publisher
Florida Atlantic University
Description
The vertebrate eye lens functions to focus light onto the retina to produce vision.
The lens is composed of an anterior monolayer of cuboidal epithelial cells that overlie a
core of organelle free fiber cells. The lens develops and grows throughout life by the
successive layering of lens fiber cells via their differentiation from lens epithelial cells.
Lens developmental defect and damage to the lens are associated with cataract formation,
an opacity of the lens that is a leading cause of visual impairment worldwide. The only
treatment to date for cataract is by surgery. Elucidating those molecules and mechanisms
that regulate the development and lifelong protection of the lens is critical toward the
development of future therapies to prevent or treat cataract. To determine those
molecules and mechanisms that may be important for these lens requirements we
employed high-throughput RNA sequencing of microdissected differentiation statespecific
lens cells to identify an extensive range of transcripts encoding proteins expressed by these functionally distinct cell types. Using this data, we identified
differentiation state-specific molecules that regulate mitochondrial populations between
lens epithelial cells that require the maintenance of a functional population of
mitochondria and lens fiber cells that must eliminate their mitochondria for their
maturation. In addition, we discovered a novel mechanism for how lens epithelial cells
clear apoptotic cell debris that could arise from damage to the lens and found that UVlight
likely compromises this system. Moreover, the data herein provide a framework to
determine novel lens cell differentiation state-specific mechanisms. Future studies are
required to determine the requirements of the identified molecules and mechanisms
during lens development, lens defense against damage, and cataract formation.
Model
Digital Document
Publisher
Florida Atlantic University
Description
Molecular chaperones guide peptide fold conformation throughout the lifetime of the peptide. One network of chaperone proteins involved in this activity, Heat shock protein 70s (Hsp70s), are well characterized at restoring peptide fold, utilizing J-domain containing protein chaperone cofactors to activate Hsp70 activity. DnaJ (Hsp40) homolog, subfamily C, member 25 (DNAJC25) is a class III transmembrane J-domain containing protein that to date is underrepresented in the literature. Recently, Hejtmancik et al. 2012. (unpublished data) have revealed that missense mutation to DNACJ25 at Pro90Leu (P90L) is strongly correlated with inherited Closed-Angle Glaucoma. Inherited mutations are well characterized for Open-Angle Glaucoma, however, prior to this finding, were unknown for Closed-Angle Glaucoma. In this report, analysis of the in vitro chaperone activity of DNAJC25 w+ and P90L is assessed utilizing an Hsp70 mediated Glucose-6-Phosphate Dehydrogenase refolding system, SWISS-MODEL predictions are performed for the J-domain structure of DNAJC25 w+ and P90L with consequent analysis of DNAJC25 Pro90 conservation relative to other type I, II, and III J-domain containing proteins. DNAJC25 P90L demonstrated decreased chaperone activity in vitro compared to w+ DNAJC25.