肺动脉高压个体中整联蛋白β3靶基因预测及生物信息学分析

目的探究肺动脉高压(PAH)个体中整联蛋白β3促进肺血管重构的分子机制,分析其可能调节的靶基因,为进一步筛选特异的靶向药物提供实验依据。方法从基因表达综合数据库选取GSE33463数据集,微阵列分析特发性PAH患者与健康对照者间差异表达的基因,R语言对测序结果中的基因进行相关性检验,找出与ITGB3具有共表达关系的基因,并进行基因本体论和KEGG富集分析,对ITGB3进行蛋白质相互作用网络分析,获得相对于ITGB3具有统计学意义的基因集合信号转导通路及蛋白与蛋白相互作用关系。小分子药物分析筛选可以调节ITGB3的潜在治疗药物。结果共表达分析结果表明,ITGB3可能与21种基因有关,其中ALAS2与ITGB3呈正相关(相关系数=0.746,P<0.001),CLK1与ITGB3呈负相关(相关系数=-0.613,P<0.001)。基因本体论分析结果表明,ITGB3主要富集的细胞组分为参与细胞黏附的蛋白质复合物和质膜受体复合物等。KEGG通路富集分析结果显示,ITGB3主要参与调控细胞黏着斑通路、磷脂酰肌醇-3-激酶/蛋白激酶B通路、肥厚型心肌病通路和扩张型心肌病通路等。蛋白相互作用网络显示,ITGB3可能与胰岛素样生长因子1(IGF-1)、IGF-1受体(IGF-1R)相互作用,形成ITGB3-IGF-1-IGF-1R复合物,活化下游信号分子。阿地芬宁、马普替林、莫能菌素等小分子药物均是可以调节ITGB3的PAH潜在治疗药物(score分别为-0.878、-0.911、-0.817,均P<0.001)。结论ITGB3可能通过与IGF-1R相结合并促进IGF-1信号通路过度活化,进而促进PAH发展。可依此研究筛选PAH的靶向治疗药物。

血小板膜糖蛋白αⅡbA477P(A446P)突变对αⅡbβ3复合物表达的影响(英文)

目的:探讨血小板膜糖蛋白αⅡbA477P(A446P)突变对αⅡbβ3蛋白表达的影响。方法:用重叠延伸PCR法对正常的αⅡb-pcDNA3.1+质粒载体进行体外定点诱变,构建了αⅡbA477P突变质粒载体;经体外真核细胞COS-7细胞转染试验后,从转录水平、蛋白质水平和膜表面复合物水平检测突变体在真核细胞内的表达。结果:突变的αⅡbA477P(A446P)基因在真核细胞内有转录,Western印迹显示细胞内有αⅡb蛋白的表达,但突变αⅡbA477P(A446P)β3复合物在细胞膜表面的表达量仅为正常αⅡbβ3复合物的12.95%。结论:αⅡbA477P(A446P)显著降低了αⅡbβ3复合物在细胞膜表面的表达,其机制可能是该位点的突变干扰了αⅡb和β3正常结合或者影响了αⅡb蛋白的正常构型。

猪口蹄疫病毒受体β3亚基的基因克隆与分子特征

目的为研究β3亚基在口蹄疫感染过程中所扮演的角色,同时也为进一步深入研究FMDV嗜性、与宿主细胞的相互作用、病毒的侵入机制等问题奠定基础。方法从正常的猪肾细胞(pk15)中克隆到了整联蛋白β3亚基的基因,对其核苷酸序列和推导的氨基酸序列以及蛋白结构进行了分析并与真核表达载体pCDNA3.1(+)相连接。结果猪整联蛋白β3亚基基因的编码区含有2 355个核苷酸,编码785个氨基酸残基,其信号肽由22个氨基酸组成;胞外域由692个氨基酸组成,含有8个潜在的糖基化位点(NXS/NXT)和57个半胱氨酸(Cys)残基;跨膜区由29个氨基酸组成;胞浆域由41个氨基酸组成。猪β3基因与羊、人、马、犬、家鼠和挪威大鼠此基因核苷酸序列的同源性分别为94.3%、90.1%、92.1%、90.9%、86.1%、86.2%,推导氨基酸序列的同源性分别为95.0%、91.8%、92.5%、91.7%、88.8%、88.7%。结论通过生物学软件分析发现猪β3亚基形成复杂的2、3级结构,其中1-22位、715-743位氨基酸区段疏水性较强,分别是该亚基的信号肽和跨膜区,以及成功构建了β3亚基的重组真核表达载体pCDNA3.1(+)β3。

Correlation of integrin β3 mRNA and vascular endothelial growth factor protein expression profiles with the clinicopathological features and prognosis of gastric carcinoma

AIM:To investigate integrin β3 mRNA and vascular endothelial growth factor (VEGF) protein expression in gastric carcinoma, and its correlation with microvascular density, growth-pattern, invasion, metastasis and prognosis. METHODS: In situ hybridization (ISH) of integrin β3 mRNA and immunohistochemistry of VEGF and CD34 protein were performed on samples from 118 patients with gastric cancer. RESULTS: The positive rate of integrin β3 mRNA in non- tumor gastric mucosa (20%) was significantly lower than that of the gastric cancer tissue (52.5%, χ2 = 10.20, P < 0.01). In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of integrin β3 mRNA were significantly higher than those in patients of expanding type (P < 0.01), stage T1-T2 (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of VEGF protein were significantly higher than those in patients of expanding type (P < 0.01), stage T1-T2 (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic orperitoneal metastasis, the mean MVD were significantly higher than those in patients of expanding type (P < 0.01), stage T1-T2 (P < 0.01), non-vessel invasion (P < 0.01), without lymphatic metastasis (P < 0.01), without hepatic and peritoneal metastasis (P < 0.01), respectively. It was found that the positive expression rate of integrin β3 mRNA was positively related to that of VEGF protein (P < 0.01) and MVD (P < 0.05), meanwhile the positive expression rate of VEGF protein was positively related to MVD (P < 0.05). The mean survival period in patients with positive expression of integrin β3 mRNA and VEGF, and MVD ≥ 54.9/mm2 was significantly shorter than that in patients with negative expression of integrin β3 mRNA (P < 0.05) and VEGF (P < 0.01), and MVD < 54.9/mm2 (P < 0.01). Five-year survival rate in patients with positive expression of integrin β3 mRNA and VEGF, and MVD ≥ 54.9/mm2 was significantly lower than those with negative expression of integrin β3 mRNA (P < 0.05), VEGF (P < 0.05), and MVD < 54.9/mm2 (P < 0.01). CONCLUSION: Integrin β3 and VEGF expression can synergistically enhance tumor angiogenesis, and may play a crucial role in invasion and metastasis of gastric carcinoma. Therefore, they may be prognostic biomarkers and novel molecular therapeutic targets.