Article

Differential expression and localization of tight junction proteins in the goat epididymis

Sung Woo Kim1, Yu-Da Jeong2, Ga-Yeong Lee2, Jinwook Lee1, Jae-Yeung Lee1, Chan-Lan Kim1, Yeoung-Gyu Ko1, Sung-Soo Lee1, Bongki Kim2,*
Author Information & Copyright
1Animal Genetic Resource Research Center, National Institute of Animal Science, RDA, Hamyang 50000, Korea.
2 Department of Animal Resources Science, Kongju National University, Yesan 32439, Korea.
*Corresponding Author: Bongki Kim, Department of Animal Resources Science, Kongju National University, Yesan 32439, Korea, Republic of. E-mail: bkkim@kongju.ac.kr.

© Copyright 2022 Korean Society of Animal Science and Technology. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Jan 05, 2022; Revised: Feb 13, 2022; Accepted: Feb 18, 2022

Published Online: Mar 28, 2022

Abstract

The blood-epididymis barrier (BEB) forms a unique microenvironment that is crucial for the maturation, protection, transport, and storage of spermatozoa in the epididymis. To characterize the function of tight junctions (TJs), which are constitutive components of the BEB, we determined the expression and localization of TJ proteins such as zonula occludens (ZO)-1, 2, and 3, occludin, and claudin3 (Cldn3) during postnatal development in the goat epididymis. To assess the expression patterns of TJ proteins in immature (3 months of age) and mature (14 months of age) goat epididymides, two different experimental methods were used including immunofluorescence labeling and western blotting. We show that, ZO-1, 2, and 3, and occludin, were strictly expressed and localized to the TJs of the goat epididymis, whereas claudin3 (Cldn3) was present in basolateral membranes as well as TJs. All TJ proteins examined were more highly expressed in the immature epididymis compared to levels in mature tissue. In conclusion, our study indicates that at least five tight junction proteins, namely ZO-1, ZO-2, ZO-3, occludin, and Cldn3, are present in TJs, and the expression strength and pattern of TJ proteins tend to be age dependent in the goat epididymis. Together, these data suggest that the distinct expression patterns of TJ proteins are essential for regulating components of the luminal contents in the epididymal epithelium and for forming adequate luminal conditions that are necessary for the maturation, protection, transport, and storage of spermatozoa in the goat epididymis.

Keywords: Blood-epididymis barrier; Tight junctions; Zonula occludens; Claudin; Occludin