Submit Data |  Help |  Video Tutorials |  News |  Publications |  FTP Download |  REST API |  Citing RGD |  Contact   

Expression of a testis-specific putative actin-capping protein associated with the developing acrosome during rat spermiogenesis.

Authors: Hurst, S  Howes, EA  Coadwell, J  Jones, R 
Citation: Hurst S, etal., Mol Reprod Dev 1998 Jan;49(1):81-91.
Pubmed: (View Article at PubMed) PMID:9406198
DOI: Full-text: DOI:10.1002/(SICI)1098-2795(199801)49:1<81::AID-MRD9>3.0.CO;2-K

Actin-capping proteins are ubiquitous components of mammalian cells. They are known to regulate the polymerization state of actin and hence indirectly control the activity of the cytoskeleton and cell shape. As part of our investigation into the molecular mechanisms that direct differentiation of a round spermatid into an elongating spermatozoa, we report on a testis-specific 1.7-kb transcript from rat testis with sequence similarities to the alpha subunit of actin-capping proteins (ACPs) from somatic cells. The transcript contains a putative cAMP-responsive motif (CREM) upstream of the initiation codon in the DNA sequence and is expressed postmeiotically, first appearing between 20 and 30 days of postnatal development. The primary amino acid sequence is 90% identical to that of a previously identified testis-specific mouse protein, gsg3, both showing approximately 40% homology to the alpha subunit of somatic ACPs. An affinity-purified polyclonal antibody to a synthetic peptide derived from the rat transcript identified a 32-kDa protein on Western blots of testicular extracts. Indirect immunofluorescent localization of the protein on frozen sections of adult rat testis showed that it is intracellular and accumulates asymmetrically in the cytoplasm of round spermatids coincident with the position of the developing acrosome. This spatial expression parallels the distribution of F-actin during sperm differentiation, supporting the hypothesis that testis-specific ACPs have an important role in determining the final shape of mature sperm heads. A disturbance in the expression of these ACPs may underlie many of the abnormalities in sperm morphology observed in infertile semen.


Gene Ontology Annotations
Objects Annotated

Additional Information

CRRD Object Information
CRRD ID: 69796
Created: 2002-01-09
Species: All species
Last Modified: 2002-01-09
Status: ACTIVE


RGD is funded by grant HL64541 from the National Heart, Lung, and Blood Institute on behalf of the NIH.