Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 985800 University of Nebraska Medical Center, Omaha, NE 68198-5800, USA.
Rapid Commun Mass Spectrom. 2010 Sep 15;24(17):2620-4. doi: 10.1002/rcm.4681.
Gelsolin is the most widely expressed member of the actin capping and severing family of proteins. There are two isoforms of gelsolin: isoform 1, a secretory (plasma) protein that is 51 amino acids longer than isoform 2, a cytosolic protein, at the N-terminus; the first 27 amino acids is a signal sequence. Both isoforms are coded by a single gene and differ as a result of alternative initiation site/splicing. The level of gelsolin in the blood and cerebrospinal fluid (CSF) is altered in many diseases including amyloidoses and other neurodegenerative disorders. Although quantitative analysis of gelsolin has been reported, lack of suitable antibodies makes it impossible to differentiate these two isoforms by immunodetection techniques and no other technique is available. Therefore, ambiguity exists whether gelsolin present in circulation is isoform 1 or also isoform 2 released from lysed cells. We report in this communication a mass spectrometric approach to identify isoform 1 of gelsolin immunopurified from human plasma and CSF. Recombinant isoform 1 was used as reference.
凝溶胶蛋白是肌动蛋白盖帽和切割蛋白家族中表达最广泛的成员。有两种凝溶胶蛋白同工型：同工型 1 是一种分泌性（血浆）蛋白，其 N 端比同工型 2 长 51 个氨基酸，同工型 2 是一种细胞质蛋白；第一个 27 个氨基酸是一个信号序列。两种同工型都由一个单一基因编码，由于不同的起始位点/剪接而有所不同。血液和脑脊液（CSF）中的凝溶胶蛋白水平在许多疾病中发生改变，包括淀粉样变性和其他神经退行性疾病。尽管已经报道了对凝溶胶蛋白的定量分析，但缺乏合适的抗体使得无法通过免疫检测技术区分这两种同工型，也没有其他技术可用。因此，循环中存在的凝溶胶蛋白是同工型 1 还是从裂解细胞中释放的同工型 2 存在歧义。我们在本通讯中报告了一种从人血浆和 CSF 中免疫纯化的凝溶胶蛋白同工型 1 的质谱鉴定方法。使用重组同工型 1 作为参考。
