328. CLAUDIN-8 IS EXPRESSED IN BOVINE TESTIS GERM CELLS

Abstract

Germline stem cells in the testis allow for the continued production of spermatozoa throughout a male’s life. These cells are capable of self-renewal and have the ability to colonise testis tissue and give rise to spermatocytes after transplantation. Identification of germ cells and other cell types within testis tissue is important for increasing understanding of germ cell biology. Work in this lab is focused on the bovine testis, and we use both germ and non-germ cell markers for cell identification and germ cell enrichment. Such markers are also used for monitoring physiological and pathological changes in testis tissue after treatments such as irradiation. At present cell type markers for germ cells are limited, particularly in livestock species. This study has therefore investigated candidate marker genes for expression in testis cells. Here, we present quantitative gene expression data for Claudin-8 (CLDN8) in testis tissue. Claudin-8 is a membrane protein involved in the formation of tight junctions, such as are formed by germ cells in the testis. We used qRT-PCR to examine the expression of CLDN8 and other candidate genes in germ cell enriched and non-enriched testis cell fractions. Our qRT-PCR analysis shows that CLDN8 is preferentially expressed in germ cell enriched fractions. Testis cell fractions were also analysed for expression of established germ cell markers such as PLZF (ZBTB16) and VASA (DDX4), as well as for Sertoli cell marker GATA4. Our analysis shows a positive correlation between expression of CLDN8 and established germ cell markers, and a negative correlation between expression of CLDN8 and established Sertoli cells markers.