HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hen, G. Articles by Friedman-Einat, M. Search for Related Content PubMed PubMed Citation Articles by Hen, G. Articles by Friedman-Einat, M.

Institute of Animal Science, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel¹ Consulting and Inventions, Nes Ziona, Moshe Levi 45A, 74207 Israel² Department of Metabolic Disorders-Diabetes, Merck Research Laboratories, Rahway, New Jersey 07065, USA³ Department of Molecular, Cellular and Developmental Biology, The University of Michigan, 830 North University Avenue, Ann Arbor, Michigan 48109-1048, USA

(Correspondence should be addressed to M Friedman-Einat; Email: einat{at}agri.huji.ac.il)

We report on the construction of a leptin bioassay based on the activation of chicken leptin receptor in cultured cells. A human embryonic kidney (HEK)-293 cell line, stably transfected with the full-length cDNA of chicken leptin receptor together with a STAT3-responsive reporter gene specifically responded to recombinant human and Xenopus leptins. The observed higher sensitivity of chicken leptin receptor to the former is in agreement with the degree of sequence similarity among these species (about 60 and 38% identical amino acids between humans and chickens, and between humans and Xenopus respectively). The specific activation of signal transduction through the chicken leptin receptor, shown here for the first time, suggests that the transition of Gln269 (implicated in the Gln-to-Pro Zucker fatty mutation in rats) to Glu in chickens does not impair its activity. Analysis of leptin-like activity in human serum samples of obese and lean subjects coincided well with leptin levels determined by RIA. Serum samples of pre- and post partum cows showed a tight correlation with the degree of adiposity. However, specific activation of the chicken leptin receptor in this assay was not observed with serum samples from broiler or layer chickens (representing fat and lean phenotypes respectively) or with those from turkey. Similar leptin receptor activation profiles were observed with cells transfected with human leptin receptor. Further work is needed to determine whether the lack of leptin-like activity in the chicken serum samples is due to a lack of leptin in this species or simply to a serum level of leptin that is below the detection threshold.

This article has been cited by other articles:

				C. G. Scanes Absolute and Relative Standards--The Case of Leptin in Poultry: First Do No Harm Poult. Sci., October 1, 2008; 87(10): 1927 - 1928. [Full Text] [PDF]