珍珠鸟和家鸡甲状旁腺激素3型受体(PTH3R)的结构与表达图谱分析

Characterization of Type 3 parathyroid hormone/parathyroid hormone-related peptide receptor in chickens and zebra finches

本研究采用RT-PCR方法,首先克隆珍珠鸟和家鸡的PTH3R基因全长cDNA序列.结果显示,家鸡PTH3R(cPTH3R)cDNA全长1632bp,编码543个氨基酸,珍珠鸟PTH3R(zPTH3R-w)cDNA序列全长1563bp,编码520个氨基酸,其蛋白均含有信号肽序列、七次跨膜区等特征性结构.此外,在珍珠鸟中还发现一个新剪接变体zPTH3R-v1,其cDNA序列全长1468bp,编码488个氨基酸,其缺失第3外显子进而导致第1跨膜结构域缺失.利用生物信息学方法,我们还对珍珠鸟和家鸡PTH3R蛋白序列进行三维建模.采用RT-PCR方法,本研究也对珍珠鸟PTH3R基因进行组织表达分析.结果显示,zPTH3R及其剪切变体zPTH3R-v1在珍珠鸟脑及外周组织中广泛表达.

The aim of this study was to clone the cDNA sequence of the chicken and zebra finch PTH3R and fur- ther analyze the tissue expression of zebra finch PTH3R. Result showed that chicken PTH3R （cPTH3R） cD- NA is 1632 bp in length and encodes a 543-arnino acid receptorl zebra finch PTH3R （zPTH3R-w） cDNA is 1563 bp in length and encodes a 520-amino acid receptor. Both cPTH3R and zPTH3R-w contain a signal peptide and seven transmembrane domains. A new splice variant of zPTH3R, named zPTH3R-vl, was also cloned in this study. It is 1468 bp in length and encodes a 488-amino acid receptor. The zPTH3R-vl lacks the 3ra exon which codes for the Ist transmembrane domain. RT-PCR assay showed that zPTH3R-w mRNA is expressed in all tissues examined except kidney, thyroid gland, pancreas, pituitary and spinal cord, while zPTH3R-vl mR- NA is expressed in all peripheral tissue and central neuronal system tissues except cerebellum.