Department of Biological Sciences, North Dakota State University, Fargo ND 58108, USA.
Gene. 2014 Jan 1;533(1):286-94. doi: 10.1016/j.gene.2013.09.046. Epub 2013 Sep 29.
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.
为了阐明生长激素受体（GHR）家族的分化，我们从一种鱼类（虹鳟）中鉴定了一种新的 GHR。分离出一个包含 2357 个核苷酸的 cDNA，发现其具有一个 71 个核苷酸的起始位点，起始位点距离 5'端最近，一个开放阅读框，编码一个 657 个氨基酸的蛋白质，一个 229 个核苷酸的单一多聚腺苷酸化位点，距离多聚 A 尾最近。根据结构分析，该蛋白被鉴定为一种 1 型 GHR（GHR1）。新的 GHR1 与之前从虹鳟中分离的两种 2 型 GHR（GHR2a 和 GHR2b）分别具有 42%和 43%的氨基酸同一性。GHR1 mRNA 在广泛的组织中表达，在肝脏、红肌和白肌中表达量最高。禁食 4 周会降低肝脏、脂肪组织和红肌中 GHR1 的稳定水平。这些发现有助于阐明 GHR 的分化和命名，并深入了解重复 GHR 类型的功能。
