Seidah N G, Gianoulakis C, Crine P, Lis M, Benjannet S, Routhier R, Chrétien M
Proc Natl Acad Sci U S A. 1978 Jul;75(7):3153-7. doi: 10.1073/pnas.75.7.3153.
Three 3-hr incubations of pars intermedia cells from 40 rat pituitaries with [35S]methionine, [3H]lysine, and [3H]leucine sufficed for the identification and chemical characterization of biosynthesized beta-lipotropin, gamma-lipotropin, and beta-endorphin. From the molecular weight, migration on polyacrylamide gels, and sequence Met5, Lys9, Leu14,17, rat beta-endorphin was shown to be identical to its sheep homologue and no trace of Leu5 beta-endorphin could be detected. Rat beta-lipotropin differs from that of sheep in its elution properties on CM-cellulose, and its sequence shows Leu2,10,14, Lys20. Rat gamma-lipotropin shows the same NH2-terminal sequence as beta-lipotropin and is again different from its sheep homologue. The identification of rat beta-lipotropin was confirmed by its selective cleavage into beta-endorphin after trypsin digestion of the citraconylated peptide, a property not observed with rat gamma-lipotropin.
用[35S]甲硫氨酸、[3H]赖氨酸和[3H]亮氨酸对40只大鼠垂体的中间部细胞进行3次3小时的孵育，足以鉴定和化学表征生物合成的β-促脂素、γ-促脂素和β-内啡肽。从分子量、在聚丙烯酰胺凝胶上的迁移以及序列Met5、Lys9、Leu14,17来看，大鼠β-内啡肽与其绵羊同源物相同，未检测到Leu5β-内啡肽的痕迹。大鼠β-促脂素在CM-纤维素上的洗脱特性与绵羊的不同，其序列显示为Leu2,10,14、Lys20。大鼠γ-促脂素显示出与β-促脂素相同的NH2-末端序列，同样与绵羊同源物不同。对经柠康酰化的肽进行胰蛋白酶消化后，大鼠β-促脂素可选择性裂解为β-内啡肽，从而证实了其鉴定结果，而大鼠γ-促脂素未观察到这一特性。
