摘　要：转化生长因子-β（TGF-β）在组织纤维化和肿瘤的发生发展中起着重要作用。应用多种生物学在线软件对TGF-β的理化性质、信号肽结构、跨膜区域、亚细胞定位、二级结构、保守结构域等进行分析。TGF-β的分子量为49 312.95 Da，蛋白分子式为C2203H3375N629O629S18，理论等电点为7.74，不稳定指数为53.82。TGF-β亲水性平均总值为-0.397，脂肪指数为76.96，其氨基酸序列的第19位甘氨酸的疏水性最大，分值为2.167，第53位酪氨酸的亲水性最大，分值为-3.233，疏水区大于亲水区。TGF-β是一个碱性、不稳定的疏水性蛋白，定位于细胞外基质（66.7%）、内质网（22.2%）和液泡（11.1%），其二级结构主要由无规则卷曲（55.81%）组成，具有4个N-糖基化，15个O-糖基化和32个磷酸化位点。此外，还发现TGF-β高表达与肿瘤的不良预后密切相关。本研究结果为进一步研究TGF-β在临床上的治疗提供新的作用靶点，并为其在生命活动中的作用机制提供了新的思路。
关键词：TGF-β；生物信息学；分子结构；信号肽结构；肿瘤相关性
中图分类号：Q811.4                                    文献标志码：ADOI：10.3969/j.issn.1007-7146.2022.01.011

Abstract: Transforming growth factor-β (TGF-β) plays an important role in the development of tissue fibrosis and tumors. The present study intends to analyze its physicochemical properties and molecular structure, which will provide new ideas and basis for further research on the mechanism of action of TGF-β in clinical treatment by providing new targets and life activities. A variety of biology online software was applied to analyze the physicochemical properties, signal peptide structure, transmembrane region, subcellular localization, secondary structure, and to conduct conserved structural domain analysis of TGF-β. The molecular weight of TGF-β is 49 312.95 Da, the protein formula is C2203H3375N629O629S18, and the theoretical isoelectric point is 7.74. And it is a basic and stable hydrophilic protein; the instability index is 53.82, belonging to stable protein; the average hydrophilic value is -0.397, and the fat index is 76.96; TGF-β is a hydrophilic protein, and glycine at the 19th position of the amino acid sequence of TGF-β has the largest hydrophobicity, with the score being 2.167; tyrosine 53th had the highest hydrophilicity, with a score of -3.233. TGF-β is a basic, unstable hydrophobic protein, localized in the extracellular matrix (66.7%), endoplasmic reticulum (22.2%) and vesicles (11.1%), respectively. The secondary structure of TGF-β was mainly composed of random coils (55.81%) with 4 N-glycosylation, 15 O-glycosylation and 32 phosphorylation sites. In addition, TGF-β high expression was closely associated with poor prognosis of tumor. These results will provide a new theoretical basis for studying the function and mechanism of action of TGF-β in life activities.
Key words: TGF-β; bioinformatics; molecular structure; signal peptide structure; tumor correlation
（Acta Laser Biology Sinica, 2022, 31(1): 079-086）