Postnatal Changes in the Expression of Claudin‐11 in the Testes and Excurrent Ducts of the Domestic Rabbit (Oryctolagus cuniculus domesticus)

Abstract

ABSTRACT:We examined the expression of claudin-11 (CLDN11) in the testes and male reproductive tracts of rabbits. The rabbit CLDN11 cDNA sequences were nearly identical with human, mouse, and bovine CLDN11. The levels of CLDN11 mRNA and protein (22 kDa) were markedly increased in the testis during adult development. On postnatal day (PND) 10, CLDN11 was colocalized with ZO-1 at the lateral contacts between adjacent Sertoli cells and was perpendicular to the basal lamina. In adult testis on PND 180, CLDN11 was codistributed with ZO1, and the pattern of immunoreactivity consisted of wavy linear tracts parallel to the basal lamina, which was different according to the spermatogenic stage. These results suggest that CLDN11 participates in inter-Sertoli cell tight junctions (TJs) at the blood-testis barrier in adult rabbits. CLDN11 was also found in the basal regions of Sertoli cells adjacent to the basal lamina in adult testis, suggesting that CLDN11 also participates in the adhesion between Sertoli cells and the basal lamina. CLDN11 mRNA and protein expressions were decreased in the adult epididymis compared with those in immature animals. In adults, CLDN11 mRNA levels were relatively high in the efferent duct, followed by those in the vas deferens, proximal corpus, and distal cauda, although low levels were observed in the initial segment and caput. On PND 10, CLDN11 immunoreactivity was identified at the apicolateral contacts between adjacent epithelial cells in the epididymis and vas deferens. In adults, CLDN11 was found in the nonciliated cells in the efferent duct and at the lateral contacts in the epithelial cells in the epididymal segments. In the caput, CLDN11 was found at the apicolateral contacts between adjacent epithelial cells, but expression was weak to negligible in the corpus of the vas deferens. CLDN11 may play an important role in TJs and cell adhesion in immature rabbit excurrent duct epithelia. In adult rabbits, CLDN11 in efferent duct epithelium and epididymal epithelium may contribute to the specific environment for sperm maturation.

Role of early life nutrition on the hypothalamic-pituitary-testicular axis of the bull

“…In the current study, the mature bulls and the HIGH calves had a similar level of testicular expression of CLDN11 with both groups having greater transcript abundance compared to LOW calves and suggests a favourable developmental benefit to the HIGH calves. In agreement, CLDN11 mRNA and protein levels were lower in the immature testes of rabbits (postnatal Day 10) in comparison with those of adults (postnatal Day 180) (Park et al 2011). Zonula occludens protein 1 (ZO1), also referred to as tight junction protein 1, is involved in blood-testis barrier function.…”

The abundance and localization of claudin‐1 and ‐5 in the adult tomcats (Felis catus) testis, tubules rectus, rete testis, efferent ductules, and epididymis

“…The localization of claudins in the tubules recti, rete testis, and efferent ductules has received surprisingly little attention. Only the localizations of claudin‐5 in the rete testis of mice (Morrow et al, 2009), claudin‐10 and ‐11 in the efferent ductules of rats (Guan et al, 2005), and rabbits (Park et al, 2011), respectively, have been demonstrated. The current study's immunostaining results revealed that claudin‐1 and ‐5 exhibit distinct cellular localization patterns in the epithelia of domestic cats' tubules recti, rete testis, and efferent ductules.…”

“…Previous studies have demonstrated that tight junctions in BTB and BEB are composed of various claudin proteins. Up-to-date, claudins 1, 3, 4, 5, 7, 8, and 11 have been found in the testis of some mammals, such as mice (Chihara et al, 2010;Gye, 2003;Mazaud-Guittot et al, 2010;Meng et al, 2005;Morita, Sasaki, Fujimoto, et al, 1999;Morrow et al, 2009Morrow et al, , 2010Stammler et al, 2016), rat (Kamimura et al, 2002;Manku et al, 2016;Stammler et al, 2016), pig (Park et al, 2011), alpaca (Guo et al, 2013), bovine (McMillan et al, 2014), horse (Lee et al, 2016;Rode et al, 2015), human (Manku et al, 2016;Stammler et al, 2016), and dog (Pörtner et al, 2020). Studies have revealed that some claudins exhibit a spermatogenic stage cycle-specific localization pattern in some species (McMillan et al, 2014;Morrow et al, 2010) but are present in all phases of the cycle in others (Mazaud-Guittot et al, 2010;Tarulli et al, 2008).…”

“…Of the claudin proteins, claudins 3 and 11 have received the most attention (Morita, Sasaki, Fujimoto, et al, 1999; Mazaud‐Guittot et al, 2010; Morrow et al, 2010; Park et al, 2011; Guo et al, 2013; Rode et al, 2015; Stammler et al, 2016; Pörtner et al, 2020); however, the expression and localization of claudin‐1 and ‐5 in BTB and BEB tight junctions have been studied less. Claudin‐1, the first identified claudin, is crucial to mammal epidermal barrier formation by forming TJ strands (Furuse et al, 2002).…”

Cytokeratin localization and basal cell differentiation in the epididymal epithelium during postnatal development of the mouse

“…We designated these cells the flask-shaped basal cells. To determine whether the flask-shaped basal cells can cross the tight-junction barrier, double labeling for GS-IB4 lectin, which is a marker of basal cells 19,20) , and tight junction protein ZO-1 21) , was performed on mouse epididymis. clearly shows a flask-shaped basal cell extending its body projection to cross the ZO1-labeled tight junction barrier and toward the lumen.…”