Regulation of testicular tight junctions by gonadotrophins in the adult Djungarian hamster in vivo.
This study aimed to assess the effect of gonadotrophin suppression and FSH replacement on testicular tight junction dynamics and blood-testis barrier (BTB) organisation in vivo, utilising the seasonal breeding Djungarian hamster. Confocal immunohistology was used to assess the cellular organisation of tight junction proteins and real-time PCR to quantify tight junction mRNA. The effect of tight junction protein organisation on the BTB permeability was also investigated using a biotin-linked tracer. Tight junction protein (claudin-3, junctional adhesion molecule (JAM)-A and occludin) localisation was present but disorganised after gonadotrophin suppression, while mRNA levels (claudin-11, claudin-3 and occludin) were significantly (two- to threefold) increased. By contrast, both protein localisation and mRNA levels for the adaptor protein zona occludens-1 decreased after gonadotrophin suppression. FSH replacement induced a rapid reorganisation of tight junction protein localisation. The functionality of the BTB (as inferred by biotin tracer permeation) was found to be strongly associated with the organisation and localisation of claudin-11. Surprisingly, JAM-A was also recognised on spermatogonia, suggesting an additional novel role for this protein in trans-epithelial migration of germ cells across the BTB. It is concluded that gonadotrophin regulation of tight junction proteins forming the BTB occurs primarily at the level of protein organisation and not gene transcription in this species, and that immunolocalisation of the organised tight junction protein claudin-11 correlates with BTB functionality.
Tarulli
Gerard A
GA
Prince Henry's Institute of Medical Research, PO Box 5152, Clayton, Victoria 3168, Australia.
Meachem
Sarah J
SJ
Schlatt
Stefan
S
Stanton
Peter G
PG
D000818:Animals; D001483:Base Sequence; D001814:Blood-Testis Barrier / Q000187:drug effects / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000235:genetics; D062465:Claudin-3; D057167:Claudins; D006224:Cricetinae; D017931:DNA Primers / Q000235:genetics; D005455:Fluorescent Antibody Technique; D005640:Follicle Stimulating Hormone / Q000494:pharmacology / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects; D062726:Junctional Adhesion Molecules; D008297:Male; D008565:Membrane Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000235:genetics; D062793:Occludin; D017111:Phodopus / Q000378:metabolism*; D010750:Phosphoproteins / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012621:Seasons; D013737:Testis / Q000378:metabolism*; D019108:Tight Junctions / Q000378:metabolism*; D014158:Transcription, Genetic; D062826:Zonula Occludens-1 Protein
C120453:CLDN11 protein, human; C568122:CLDN3 protein, human; D015815:Cell Adhesion Molecules; D062465:Claudin-3; D057167:Claudins; D017931:DNA Primers; D062726:Junctional Adhesion Molecules; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C568985:OCLN protein, human; D062793:Occludin; D010750:Phosphoproteins; D012333:RNA, Messenger; C569042:TJP1 protein, human; D062826:Zonula Occludens-1 Protein; D005640:Follicle Stimulating Hormone