Expression of tumor necrosis factor-alpha-related apoptosis-inducing ligand and its receptors in rat testis during development.
Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor-alpha family of cytokines that is known to induce apoptosis upon binding to its death domain-containing receptors, DR4/TRAIL-R1 and DR5/TRAIL-R2. Two additional TRAIL receptors, DcR1/TRAIL-R3 and DcR2/TRAIL-R4, lack functional death domains and act as decoy receptors for TRAIL. In this study, the presence of TRAIL and its receptors was investigated in the rat testis during development. TRAIL and its receptors were immunolocalized to the different testicular cell types. TRAIL and its receptors were also identified in the rat testis in terms of protein and mRNA. Our immunohistochemical studies indicate that TRAIL, DR5/TRAIL-R2, and DcR2-TRAIL-R4 are detected in Leydig cells, whereas ligand and all receptors are localized in germ cells. TRAIL was permanently immunodetected in germ cells from the fetal stage to adulthood, whereas its receptors were immunolocalized exclusively in postmeiotic germ cells. The expression of TRAIL and receptor mRNAs was consistent with the immunodetection of TRAIL and receptor proteins. Indeed, TRAIL ligand mRNA was also identified in the rat testis from the fetal stage to adulthood. The mRNAs of the death receptors, DR4/TRAIL-R1 and DR5/TRAIL-R2, were weakly detected during the perinatal period and increased from the pubertal stage to adulthood. The mRNAs of the decoy receptors, DcR1 and DcR2, were present in the rat testis at all ages studied, but the DcR2/TRAIL-R4 mRNa level was higher from the pubertal period to adulthood. Together, the present findings demonstrate that 1) TRAIL and its receptors are expressed in the testis during normal development, and 2) TRAIL protein is present in the different germ cell types, whereas its receptors were predominantly detected in the postmeiotic germ cells.
Grataroli
Renée
R
Institut National de la Santé et de la Recherche Médicale, INSERM U-407, Communications Cellulaires en Biologie de la Reproduction, Faculté de Médecine Lyon-Sud, F-69921 Oullins Cedex, France. gratarol@lsgrisn1.univ-lyon1.fr
Vindrieux
David
D
Gougeon
Alain
A
Benahmed
Mohamed
M
D000375:Aging; D000818:Animals; D058851:GPI-Linked Proteins; D015870:Gene Expression; D007150:Immunohistochemistry; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis / Q000235:genetics; D053320:Receptors, Tumor Necrosis Factor, Member 10c; D012741:Sexual Maturation; D013094:Spermatozoa / Q000737:chemistry; D013737:Testis / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism*; D053319:Tumor Necrosis Factor Decoy Receptors
D058851:GPI-Linked Proteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053320:Receptors, Tumor Necrosis Factor, Member 10c; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C108661:TNFRSF10C protein, human; C505644:Tnfrsf10b protein, rat; D053319:Tumor Necrosis Factor Decoy Receptors; C509611:decoy receptor 2, rat