TY - JOUR
T1 - Identification of three putative GnRH receptor subtypes in vertebrates
AU - Troskie, B.
AU - Illing, N.
AU - Rumbak, E.
AU - Sun, Y. M.
AU - Hapgood, J.
AU - Sealfon, S.
AU - Conklin, D.
AU - Millar, R.
N1 - Funding Information:
We acknowledge support from the Medical Research Council, The Foundation for Research Development, Grant RO3 TW00592–01 from Fogarty International and the University of Cape Town. We thank Dr. K. Whitlock, and Dr. A. Fleming for providing teleost and lizard material.
PY - 1998/12
Y1 - 1998/12
N2 - The majority of vertebrates have two or three forms of gonadotropin- releasing hormone (GnRH), which appear to have arisen by successive gene duplication events. This suggests the possibility of concordant gene duplications of the GnRH receptor to produce two or more cognate receptors. Since the extracellular loop 3 (EC3) domain of mammalian GnRH receptors plays a role in distinguishing the different forms of GnRH, we have contemplated that the sequence of this domain will differ significantly in the putative cognate receptors. Degenerate oligonucleotides encoding the sequences of the transmembrane domains preceding and following EC3 were used for PCR amplification of genomic DNA from zebra fish (Brachydanio rerio), goldfish (Carassius auratus), African clawed frog (Xenopus laevis), chicken (Gallus domesticus), and lizard (Agama atra). Isolation and sequencing of specific clones revealed that they fell into three groups. Two of these were most similar to the mammalian pituitary GnRH receptor and were therefore designated Type IA anti Type IB. The third form (designated Type II) was most different from the others and was identified in Xenopus, lizard, and human DNA. These findings support the concept of the existence of three distinct GnRH receptors, which have evolved in conjunction with three distinct GnRH ligand classes present in many vertebrates.
AB - The majority of vertebrates have two or three forms of gonadotropin- releasing hormone (GnRH), which appear to have arisen by successive gene duplication events. This suggests the possibility of concordant gene duplications of the GnRH receptor to produce two or more cognate receptors. Since the extracellular loop 3 (EC3) domain of mammalian GnRH receptors plays a role in distinguishing the different forms of GnRH, we have contemplated that the sequence of this domain will differ significantly in the putative cognate receptors. Degenerate oligonucleotides encoding the sequences of the transmembrane domains preceding and following EC3 were used for PCR amplification of genomic DNA from zebra fish (Brachydanio rerio), goldfish (Carassius auratus), African clawed frog (Xenopus laevis), chicken (Gallus domesticus), and lizard (Agama atra). Isolation and sequencing of specific clones revealed that they fell into three groups. Two of these were most similar to the mammalian pituitary GnRH receptor and were therefore designated Type IA anti Type IB. The third form (designated Type II) was most different from the others and was identified in Xenopus, lizard, and human DNA. These findings support the concept of the existence of three distinct GnRH receptors, which have evolved in conjunction with three distinct GnRH ligand classes present in many vertebrates.
UR - http://www.scopus.com/inward/record.url?scp=0032409997&partnerID=8YFLogxK
U2 - 10.1006/gcen.1998.7156
DO - 10.1006/gcen.1998.7156
M3 - Article
C2 - 9843635
AN - SCOPUS:0032409997
SN - 0016-6480
VL - 112
SP - 296
EP - 302
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
IS - 3
ER -