TY - JOUR
T1 - The mRNA Expression of Insulin Receptor Isoforms (IR-A and IR-B) and IGFR-2 in the Bovine Corpus Luteum during the Estrous Cycle, Pregnancy, and Induced Luteolysis
AU - Neuvians, Tanja Pascale
AU - Pfaffl, Michael Walter
AU - Berisha, Bajram
AU - Schams, Dieter
N1 - Funding Information:
We would like to thank Ch. Fochtmann, Dr. W. Kraetzl for the surgical help in collecting the CL, and Dr. R. Ivell for critical reading of the manuscript. Furthermore, we are deeply grateful for financial support of this project by the “H. Wilhelm Schaumann Stiftung,” Hamburg, Germany, and the German Research Foundation (DFG, Scha 257/14).
PY - 2003/11
Y1 - 2003/11
N2 - Isoform A of the human insulin receptor and the IGF-receptor type 2 (IGFR-2) are both receptors for insulin-like growth factor II (IGF II), which plays a major role in luteal development and function in bovine species. The objective of this study was to determine if both insulin receptor isoforms and IGFR-2 were expressed in the bovine corpus luteum (CL) and if they were regulated during the estrous cycle, pregnancy, and induced luteolysis. CL were collected at the slaughterhouse. For induced luteolysis, CL were obtained by transvaginal ovariectomy at 2, 4, 12, 48, and 64 h after prostaglandin (PG) F2α-injection. Real-time RT-PCR was applied to investigate mRNA expression. Two alternatively spliced transcripts encoding the insulin receptor were detected in bovine CL. These two isoforms corresponded to the known isoforms A (IR-A) and B (IR-B) in humans. IR-A mRNA predominated in bovine CL and was significantly down-regulated on d 5-7. IR-B mRNA was significantly up-regulated in the late luteal stage and during early pregnancy. IR-A showed a significant down-regulation at 48 h after PGF2α. IGFR-2 mRNA was significantly up-regulated in mid and late luteal stages (d 8-18). It is proposed that the differential mRNA expression of IR-A and IGFR-2, both binding IGF II, may play a role in the development and function of the bovine corpus luteum.
AB - Isoform A of the human insulin receptor and the IGF-receptor type 2 (IGFR-2) are both receptors for insulin-like growth factor II (IGF II), which plays a major role in luteal development and function in bovine species. The objective of this study was to determine if both insulin receptor isoforms and IGFR-2 were expressed in the bovine corpus luteum (CL) and if they were regulated during the estrous cycle, pregnancy, and induced luteolysis. CL were collected at the slaughterhouse. For induced luteolysis, CL were obtained by transvaginal ovariectomy at 2, 4, 12, 48, and 64 h after prostaglandin (PG) F2α-injection. Real-time RT-PCR was applied to investigate mRNA expression. Two alternatively spliced transcripts encoding the insulin receptor were detected in bovine CL. These two isoforms corresponded to the known isoforms A (IR-A) and B (IR-B) in humans. IR-A mRNA predominated in bovine CL and was significantly down-regulated on d 5-7. IR-B mRNA was significantly up-regulated in the late luteal stage and during early pregnancy. IR-A showed a significant down-regulation at 48 h after PGF2α. IGFR-2 mRNA was significantly up-regulated in mid and late luteal stages (d 8-18). It is proposed that the differential mRNA expression of IR-A and IGFR-2, both binding IGF II, may play a role in the development and function of the bovine corpus luteum.
KW - Bovine
KW - Corpus luteum
KW - IGFR-2
KW - IR-A
KW - Insulin receptor
UR - http://www.scopus.com/inward/record.url?scp=0347951408&partnerID=8YFLogxK
U2 - 10.1385/ENDO:22:2:93
DO - 10.1385/ENDO:22:2:93
M3 - Article
C2 - 14665712
AN - SCOPUS:0347951408
SN - 1355-008X
VL - 22
SP - 93
EP - 99
JO - Endocrine
JF - Endocrine
IS - 2
ER -