Characterization of a novel growth hormone receptor-encoding cDNA in rainbow trout and regulation of its expression by nutritional state.
To clarify the divergence of the growth hormone receptor (GHR) family, we characterized a novel GHR from a teleost fish (rainbow trout). A 2357-nt cDNA was isolated and found to contain a single initiation site 71 nt from the most 5' end, an open reading frame of 1971 nt encoding a 657-amino acid protein, and a single polyadenylation site 229 nt from the poly-A tail. Based on structural analysis, the protein was identified as a type 1 GHR (GHR1). The new GHR1 shares 42% and 43% amino acid identity, respectively, with GHR2a and GHR2b, the two type 2 GHRs isolated from trout previously. GHR1 mRNA was found in a wide array of tissues with the highest expression in the liver, red muscle, and white muscle. Fasting animals for 4 weeks reduced steady state levels of GHR1 in the liver, adipose, and red muscle. These findings help clarify the divergence and nomenclature of GHRs and provide insight into the function of duplicated GHR types.
Department of Biological Sciences, North Dakota State University, Fargo ND 58108, USA.
Chad N
CN
Walock
Jeffrey D
JD
Kittilson
Mark A
MA
Sheridan
D000818:Animals; D018076:DNA, Complementary; D005786:Gene Expression Regulation; D009752:Nutritional Status; D017686:Oncorhynchus mykiss / Q000235:genetics*; D016366:Open Reading Frames; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D011986:Receptors, Somatotropin / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018076:DNA, Complementary; D012333:RNA, Messenger; D011986:Receptors, Somatotropin
Akt; Bp; CT; DNA complementary to RNA; ERK; FSGD; Functional divergence of duplicated genes; GH; GHR; Gene expression; JAK; Molecular evolution; PI3K; PRLR; RACE; RT-PCR; SEM; SLR; STAT; TBE; UTR; base pair; cDNA; extracellular signal-regulated kinase; fish specific genome duplication; growth hormone; growth hormone receptor; janus kinase; mRNA; messenger RNA; nt; nucleotide; phosphatidylinositide 3-kinase; prolactin receptor; protein kinase B; rapid amplification of cDNA ends; reverse transcription polymerase chain reaction; signal transducer and activator of transcription; somatolactin receptor; standard error of the mean; threshold cycle number; tris–borate–ethylenediaminetetraacetic acid; untranslated region