Chew Geoffrey H, Galloway Lamar C, McIntyre Neil R, Schroder Laura Aaron, Richards Karla M, Miller Scott A, Wright David W, Merkler David J
Department of Chemistry, University of South Florida, 4202 E. Fowler Ave., SCA 400, Tampa, FL 33620-5250, USA.
FEBS Lett. 2005 Aug 29;579(21):4678-84. doi: 10.1016/j.febslet.2005.06.089.
Ubiquitin (Ub) and the ubiquitin-like proteins (UBLs) mediate an array of cellular functions. These proteins contain a C-terminal glycine residue that is key to their function. Oxidative conversion of C-terminal glycine-extended prohormones to the corresponding alpha-amidated peptide is one step in the biosynthesis of bioactive peptide hormones. The enzyme catalyzing this reaction is peptidylglycine alpha-amidating monooxygenase (PAM). We report herein that Ub is a PAM substrate with a (V/K)(amidation) that is similar to other known peptide substrates. This work is significant because PAM and the UBLs co-localize to the hypothalamus and the adrenal medulla and are both over-expressed in glioblastomas.
泛素(Ub)和类泛素蛋白(UBLs)介导一系列细胞功能。这些蛋白质含有一个C末端甘氨酸残基,这对它们的功能至关重要。C末端甘氨酸延伸的激素原氧化转化为相应的α-酰胺化肽是生物活性肽激素生物合成的一个步骤。催化此反应的酶是肽基甘氨酸α-酰胺化单加氧酶(PAM)。我们在此报告,Ub是一种PAM底物,其(V/K)(酰胺化)与其他已知肽底物相似。这项工作意义重大,因为PAM和UBLs共定位于下丘脑和肾上腺髓质,且在胶质母细胞瘤中均过度表达。