TY - JOUR
T1 - Decreased expression of cold-inducible RNA-binding protein (CIRP) in male germ cells at elevated temperature
AU - Nishiyama, Hiroyuki
AU - Danno, Shouzou
AU - Kaneko, Yoshiyuki
AU - Itoh, Katsuhiko
AU - Yokoi, Hiromichi
AU - Fukumoto, Manabu
AU - Okuno, Hiroshi
AU - Millán, José Luis
AU - Matsuda, Tadashi
AU - Yoshida, Osamu
AU - Fujita, Jun
PY - 1998/1
Y1 - 1998/1
N2 - Physiological scrotal hypothermia is necessary for normal spermatogenesis and fertility in mammals. Cirp is a recently identified cold- inducible RNA-binding protein that is inducible at 32°C in mouse somatic cells in vitro. Cirp is constitutively expressed in the testis of mouse and structurally highly similar to RBM1, a candidate for the human azoospermia factor. To elucidate the role played by Cirp in spermatogenesis, we investigated its expression levels during spermatogenesis and after heat stress. In the mouse testis, cirp mRNA was detected in the germ cells, and the level varied depending on the stage of differentiation. Also, a high level of Cirp protein was detected immunohistochemically in the nucleus of primary spermatocytes. Expression of Cirp was decreased in the GC-2spd(ts) mouse germ cell line when culture temperature was raised from 32°C to 37°C. When mouse testis was exposed to heat stress by experimental cryptorchidism or immersion of the lower abdomen in warm (42°C) water, the expression of Cirp was decreased in the testis within 6 hours after either treatment. In human testis with varicocele analyzed immunohistochemically, germ cells expressed less Cirp protein than those in the testis without varicocele. These results demonstrated that CIRP expression is down-regulated at elevated temperature in male germ cells of mice and humans. Analysis of Cirp expression in the testes will help elucidate the molecular mechanisms leading to male infertility.
AB - Physiological scrotal hypothermia is necessary for normal spermatogenesis and fertility in mammals. Cirp is a recently identified cold- inducible RNA-binding protein that is inducible at 32°C in mouse somatic cells in vitro. Cirp is constitutively expressed in the testis of mouse and structurally highly similar to RBM1, a candidate for the human azoospermia factor. To elucidate the role played by Cirp in spermatogenesis, we investigated its expression levels during spermatogenesis and after heat stress. In the mouse testis, cirp mRNA was detected in the germ cells, and the level varied depending on the stage of differentiation. Also, a high level of Cirp protein was detected immunohistochemically in the nucleus of primary spermatocytes. Expression of Cirp was decreased in the GC-2spd(ts) mouse germ cell line when culture temperature was raised from 32°C to 37°C. When mouse testis was exposed to heat stress by experimental cryptorchidism or immersion of the lower abdomen in warm (42°C) water, the expression of Cirp was decreased in the testis within 6 hours after either treatment. In human testis with varicocele analyzed immunohistochemically, germ cells expressed less Cirp protein than those in the testis without varicocele. These results demonstrated that CIRP expression is down-regulated at elevated temperature in male germ cells of mice and humans. Analysis of Cirp expression in the testes will help elucidate the molecular mechanisms leading to male infertility.
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M3 - Article
C2 - 9422546
AN - SCOPUS:0031984249
VL - 152
SP - 289
EP - 296
JO - American Journal of Pathology
JF - American Journal of Pathology
SN - 0002-9440
IS - 1
ER -