Importance of the basement membrane protein SPARC for viability and fertility in Caenorhabditis elegans.

Publication Year
1998

Type

Journal Article
Abstract

The basement membrane is a specialized extracellular matrix located at epithelial-mesenchymal boundaries that supports cell adhesion, migration, and proliferation; it is highly conserved between invertebrates and vertebrates [1,2]. One of its component proteins, SPARC (osteonectin/BM-40), binds calcium and collagens, and can modulate cell-matrix interactions, so altering cell shape, growth, and differentiation [3,5]. The tissue distribution of a secreted fusion protein containing SPARC and green fluorescent protein (GFP) was analyzed in Caenorhabditis elegans. The protein localized to most basement membranes along body wall and sex muscles, and was also deposited around the pharynx and the gonad, in the spermatheca and at the distal tip cells. The contributions of SPARC to C. elegans development were determined using RNA interference, which accurately phenocopies loss-of-function defects [6-8]. A reduction in the amount of SPARC protein resulted in embryonic or larval lethality in a significant proportion of progeny. Those that survived developed a 'clear' phenotype characterized by a lack of gut granules, which made the animals appear transparent, plus small size, and sterility or reduced fecundity. No significant morphological abnormalities were observed, indicating that SPARC plays a regulatory rather than structural role in modulating cell-matrix interactions during normal development and reproduction.

Journal
Curr Biol
Volume
8
Issue
23
Pages
1285-8
Date Published
11/1998
ISSN Number
0960-9822
Alternate Journal
Curr. Biol.
PMID
9822581