骨膜素是一种由 POSTN 基因编码的基质细胞蛋白，通过选择性剪接产生十种不同的骨膜素亚型，分子量范围为 78 至 91 kDa。已知它可以促进原纤维形成、组织细胞外基质并结合整合素受体以诱导细胞信号传导。它不仅是伤口愈合过程的关键组成部分，还参与了特应性皮炎、哮喘和癌症等不同疾病的发病机制。在健康和疾病中，不同骨膜素亚型的功能很大程度上是未知的。精确确定给定人类样本的亚型图谱的能力对于表征其功能意义至关重要。骨膜素亚型的鉴定通常使用基于 RT-PCR 的方法在转录水平上进行，但由于序列同质性较高，蛋白质水平上的鉴定一直具有挑战性。自上而下的蛋白质组学，即通过质谱法测量整个蛋白质，为异构体鉴定提供了一种快速可靠的方法。在这里，我们提出了一种完全开发的自上而下的质谱分析方法，用于在蛋白质水平上表征骨膜蛋白剪接亚型。版权所有 © 2024 Rusbjerg-Weberskov、Gant、Chamot-Rooke、Nielsen 和 Enghild。

Periostin is a matricellular protein encoded by the POSTN gene that is alternatively spliced to produce ten different periostin isoforms with molecular weights ranging from 78 to 91 kDa. It is known to promote fibrillogenesis, organize the extracellular matrix, and bind integrin-receptors to induce cell signaling. As well as being a key component of the wound healing process, it is also known to participate in the pathogenesis of different diseases including atopic dermatitis, asthma, and cancer. In both health and disease, the functions of the different periostin isoforms are largely unknown. The ability to precisely determine the isoform profile of a given human sample is fundamental for characterizing their functional significance. Identification of periostin isoforms is most often carried out at the transcriptional level using RT-PCR based approaches, but due to high sequence homogeneity, identification on the protein level has always been challenging. Top-down proteomics, where whole proteins are measured by mass spectrometry, offers a fast and reliable method for isoform identification. Here we present a fully developed top-down mass spectrometry assay for the characterization of periostin splice isoforms at the protein level.Copyright © 2024 Rusbjerg-Weberskov, Gant, Chamot-Rooke, Nielsen and Enghild.