Furmaniak J, Hashim F A, Buckland P R, Petersen V B, Beever K, Howells R D, Smith B R
FEBS Lett. 1987 May 11;215(2):316-22. doi: 10.1016/0014-5793(87)80169-2.
An investigation of the properties of TSH receptors on FRTL5 cells using affinity labelling with a 125I-labelled photoactive derivative of TSH is described. Our studies suggest that FRTL5 cells contain 2 principal types of cell surface TSH receptors. One form, probably a precursor, consists of a single polypeptide chain (Mr 120,000) with an intrachain loop of amino acids formed by a disulphide bridge. The other type of receptor consists of a water-soluble A chain (Mr 55,000) linked to an amphiphilic B chain (Mr 35,000) by a disulphide bridge. The 2 chain structure is probably derived from the single chain 120,000 protein by enzymatic cleavage of peptide sequences within the loop of amino acids formed by the intrachain disulphide bridge.
本文描述了使用125I标记的促甲状腺激素（TSH）光活性衍生物进行亲和标记，对FRTL5细胞上TSH受体特性的研究。我们的研究表明，FRTL5细胞含有两种主要类型的细胞表面TSH受体。一种形式可能是前体，由一条单多肽链（分子量120,000）组成，链内有一个由二硫键形成的氨基酸环。另一种类型的受体由一条水溶性A链（分子量55,000）和一条两亲性B链（分子量35,000）通过二硫键相连组成。这种二链结构可能是由单链120,000蛋白通过链内二硫键形成的氨基酸环内肽序列的酶切作用衍生而来。
