Mouse RC/BTB2, a Member of the RCC1 Superfamily, Localizes to Spermatid Acrosomal Vesicles

Authors

Jiannan Wang, Virginia Commonwealth University
Maria E. Teves, Virginia Commonwealth University
Xuening Shen, Virginia Commonwealth UniversityFollow
David R. Nagarkatti-Gude, Virginia Commonwealth UniversityFollow
Rex A. Hess, University of Illinois at Urbana-Champaign
Scott C. Henderson, Virginia Commonwealth UniversityFollow
Jerome F. Strauss III, Virginia Commonwealth UniversityFollow
Zhibing Zhang, Virginia Commonwealth UniversityFollow

Document Type

Article

Original Publication Date

2012

Journal/Book/Conference Title

PLOS ONE

Volume

7

DOI of Original Publication

10.1371/journal.pone.0039846

Comments

Originally published at: http://dx.doi.org/10.1371/journal.pone.0039846

Date of Submission

November 2014

Abstract

Mouse RC/BTB2 is an unstudied protein of the RCC1 (Regulator of Chromosome Condensation) superfamily. Because of the significant remodeling of chromatin that occurs during spermiogenesis, we characterized the expression and localization of mouse RC/BTB2 in the testis and male germ cells. The Rc/btb2 gene yields two major transcripts: 2.3 kb Rc/btb2-s, present in most somatic tissues examined; and 2.5 kb Rc/btb2-t, which contains a unique non-translated exon in its 5′-UTR that is only detected in the testis. During the first wave of spermatogenesis, Rc/btb2-t mRNA is expressed from day 8 after birth, reaching highest levels of expression at day 30 after birth. The full-length protein contains three RCC1 domains in the N-terminus, and a BTB domain in the C-terminus. In the testis, the protein is detectable from day 12, but is progressively up-regulated to day 30 and day 42 after birth. In spermatids, some of the protein co-localizes with acrosomal markers sp56 and peanut lectin, indicating that it is an acrosomal protein. A GFP-tagged RCC1 domain is present throughout the cytoplasm of transfected CHO cells. However, both GFP-tagged, full-length RC/BTB2 and a GFP-tagged BTB domain localize to vesicles in close proximity to the nuclear membrane, suggesting that the BTB domain might play a role in mediating full-length RC/BTB2 localization. Since RCC1 domains associate with Ran, a small GTPase that regulates molecular trafficking, it is possible that RC/BTB2 plays a role in transporting proteins during acrosome formation.

Rights

© 2012 Wang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Is Part Of

VCU Obstetrics and Gynecology Publications