ISOLATION AND CHARACTERIZATION OF GROWTH HORMONE RECEPTORS SUBTYPES IN ZEBRAFISH (DANIORERIO)

DI PRINZIO, C.; BOTTA, P.; ARRANZ, S.E.

Mar del Plata, Argentina

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2007

Sociedad Argentina de Investigacion en Bioquímica y de Bilogía Molecular

ISOLATION AND CHARACTERIZATION OF THEGROWTH HORMONE RECEPTOR IN PEJERREY(ODONTESTHESBONARIENSIS)Botta PE, Sciara AA, Arranz SE.IBR-CONICET, FCByF, UNR, Suipacha 531, S2000LRK, Rosario.E-mail: botta@ibr.gov.arGrowth hormone (GH) is a pluripotent regulator that is involved inmetabolism and linear growth in fish. It exerts its functionsinteracting with a GH receptor (GHR) on the cell membrane of thetarget tissues. GHR belongs to the hematopoietic cytokine receptorsuperfamily, it has a single extracellular domain with conservedcysteine residues (Cys) that are involved in the GH binding, onetransmembrane domain, and one intracellular domain withconserved regions and conserved tyrosine residues (Tyr). There aretwo types of GHRs in fish (GHRI and GHRII) that differ in thenumber of Cys and Tyr between each other. It has been proved thatthe effect of GH in growth is closely related with the GHRtranscription level in liver. Our group is interested in theendocrinology of growth in Pejerrey (Atheriniformes). We arecharacterizing the GH receptor in this species.We isolated a 1500bp cDNA sequence that covers almost the entirely open readingframe of the receptor. It presents a 70% homology with perciformesGHRs, and it has all the features of GHRs type II. We detectedtranscripts of the receptor in 14 organs. ghrII expression wasmeasured in fish injected with recombinant pjGH using a RT-PCRsemiquantitative assay. Although the level of IGF-I mRNAincreased significantly 9 h post injection, no variation in thetranscription level ofGHRwas found up to 24 h post injection.