Focal adhesion kinase-Tyr407 and -Tyr397 exhibit antagonistic effects on blood-testis barrier dynamics in the rat.
AuthorsLie PP, Mruk DD, Mok KW, Su L, Lee WM, Cheng CY,
JournalProc Natl Acad Sci U S A
PubMed ID22797892
'Focal adhesion kinase (FAK), a nonreceptor protein tyrosine kinase, displays phosphorylation-dependent localization in the seminiferous epithelium of adult rat testes. FAK is an integrated component of the blood-testis barrier (BTB) involved in regulating Sertoli cell adhesion via its effects on the occludin-zonula occludens-1 complex. Herein, we report that p-FAK-Tyr(407) and ... More
rpS6 regulates blood-testis barrier dynamics through Akt-mediated effects on MMP-9.
AuthorsMok KW, Mruk DD, Cheng CY,
Journal
PubMed ID25217631
'Mammalian target of rapamycin complex 1 (mTORC1) is an emerging regulator of blood-tissue barriers that utilizes ribosomal protein S6 (rpS6) as the downstream signaling molecule. To explore the role of rpS6 in blood-testis barrier (BTB) function, a constitutively active quadruple rpS6 phosphomimetic mutant was constructed in mammalian expression vector and ... More
Claudin-1 has tumor suppressive activity and is a direct target of RUNX3 in gastric epithelial cells.
AuthorsChang TL, Ito K, Ko TK, Liu Q, Salto-Tellez M, Yeoh KG, Fukamachi H, Ito Y,
JournalGastroenterology
PubMed ID19706291
'The transcription factor RUNX3 is a gastric tumor suppressor. Tumorigenic Runx3(-/-) gastric epithelial cells attach weakly to each other, compared with nontumorigenic Runx3(+/+) cells. We aimed to identify RUNX3 target genes that promote cell-cell contact to improve our understanding of RUNX3''s role in suppressing gastric carcinogenesis. We compared gene expression ... More
Distribution of the tight junction proteins ZO-1, occludin, and claudin-4, -8, and -12 in bladder epithelium.
AuthorsAcharya P, Beckel J, Ruiz WG, Wang E, Rojas R, Birder L, Apodaca G,
JournalAm J Physiol Renal Physiol
PubMed ID15068973
'In mammals, the bladder stores urine without permitting the passage of urine contents into the bloodstream, a function, in part, of the uroepithelial-associated tight junction complex. The protein constituents that make up this high-resistance barrier in the bladder are currently unknown, although the claudins, a multigene family, are thought to ... More
Differential expression of claudin tight junction proteins in the human cortical nephron.
AuthorsKirk A, Campbell S, Bass P, Mason J, Collins J
JournalNephrol Dial Transplant
PubMed ID20124215
In renal tubules, paracellular permeability is tightly controlled to facilitate solute absorption and urinary concentration and is regulated by tight junctions, which incorporate claudin proteins. There is very limited information confirming the localization of these proteins in the human renal cortex. Most data is inferred from mouse, bovine and rabbit ... More
Enhanced immunohistochemical resolution of claudin proteins in glycolmethacrylate-embedded tissue biopsies.
AuthorsCollins JE, Kirk A, Campbell SK, Mason J, Wilson SJ,
JournalMethods Mol Biol
PubMed ID21717371
There are a number of disadvantages with conventional tissue immunohistochemistry for accurate -localisation of claudin proteins. Traditionally, tissue cryopreservation or formaldehyde fixation with wax embedding is utilised prior to sectioning and antibody localisation. Wax embedding gives better morphological preservation than frozen tissue, but the required use of chemical cross-linking fixatives ... More
Spermatogonial stem cells alone are not sufficient to re-initiate spermatogenesis in the rat testis following adjudin-induced infertility.
AuthorsMok KW, Mruk DD, Lee WM, Cheng CY
JournalInt J Androl
PubMed ID21696392
The blood-testis barrier (BTB) is a unique ultrastructure in the testis, which creates a specialized microenvironment in the seminiferous epithelium known as the apical (or adluminal) compartment for post-meiotic germ-cell development and for maintenance of an immunological barrier. In this study, we have demonstrated unequivocally that a functional and intact ... More