Epidermal growth factor receptor pathway substrate 8 (Eps8) expression in maturing testis.
OBJECTIVE
Although epidermal growth factor receptors are expressed in the testes, whether they signal through epidermal growth factor receptor pathway substrate 8 (Eps8) is unknown. Here we evaluated the expression pattern of Eps8 in the maturing testis.


METHODS
The expression of Eps8 was analysed by Northern blotting, immunocytochemistry and Western blotting in primary Sertoli cell cultures and in testicular tissue of rodents.


RESULTS
Eps8 is specifically expressed in gonocytes, Leydig and Sertoli cells of the neonatal rats and in Leydig and Sertoli cells of the adult rats and mice. Although gonocytes express Eps8, no signal was found in prepubertal or mature spermatogonia and the expression level of Eps8 in Sertoli cells increases with age. No regulation of Eps8 expression in primary immature rat Sertoli cells by Follicle stimulating hormone (FSH) was detected by Western blotting.


CONCLUSIONS
Eps8 seems to be involved in the growth factor-controlled regulation of cell proliferation and differentiation in the seminiferous epithelium. Eps8 is a possible marker for gonocytes and in Sertoli cells it could be involved in crosstalk with other growth factor pathways.
Institute of Reproductive Medicine of the University, Domagkstr. 11, D-48129 Munster, Germany.
Alain
A
Wunsch
Kai
K
Strothmann
Manuela
M
Simoni
Jörg
J
Gromoll
Eberhard
E
Nieschlag
C Marc
CM
Luetjens
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002460:Cell Line; D017931:DNA Primers; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D007985:Leydig Cells / Q000166:cytology / Q000502:physiology; D008297:Male; D011506:Proteins / Q000235:genetics*; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D051381:Rats; D017207:Rats, Sprague-Dawley; D012708:Sertoli Cells / Q000502:physiology*; D012741:Sexual Maturation; D013090:Spermatocytes / Q000166:cytology / Q000502:physiology; D013737:Testis / Q000254:growth & development*
D048868:Adaptor Proteins, Signal Transducing; D017931:DNA Primers; C498142:Eps8 protein, rat; D011506:Proteins; D012313:RNA