HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 73/5/1032    most recent biolreprod.105.040972v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Stein, K. K. Articles by Myles, D. G. Search for Related Content PubMed PubMed Citation Articles by Stein, K. K. Articles by Myles, D. G. Agricola Articles by Stein, K. K. Articles by Myles, D. G.

Defects in Secretory Pathway Trafficking During Sperm Development in Adam2 Knockout Mice¹

Section of Molecular and Cellular Biology,⁴ Department of Cell Biology and Human Anatomy, School of Medicine,⁵ University of California, Davis, Davis, California 95616

Adam2-null and Adam3-null male mice exhibit reduced levels of one or more ADAM proteins on mature sperm, in addition to the loss of the genetically targeted protein. ADAM protein loss was believed to occur posttranslationally, although the timing of loss and the mechanism by which the loss occurred were not explored. In this study we have found that in Adam3-null mice, fertilin beta (also known as ADAM2) is lost during the formation of testicular sperm. In Adam2-null males, most cyritestin (ADAM3) protein is also lost at this stage, but 25% of cyritestin is lost later, during sperm passage through the epididymis. Although normal levels of cyritestin are synthesized and acquire Endoglycosidase H resistance, indicating transit through the Golgi, the protein does not reach the cell surface. We also discovered that the majority of both fertilin beta and cyritestin are found in a Triton X-100 insoluble compartment on testicular sperm, when most of the cyritestin was observed on the cell surface. This insoluble compartment may represent a sorting platform, because in Adam2-knockout cells, only a small fraction of the cyritestin becomes Triton X-100 insoluble. Thus, it appears that cyritestin loss in Adam2-knockout mice may result, at least in part, from a disruption in protein trafficking.

fertilization, gamete biology, sperm, spermatogenesis, testis

² Correspondence. Fax: 530 752 7522; dgmyles{at}ucdavis.edu

³ Current address: Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892