摘要
脊椎动物中,非晶状体βγ-晶状体蛋白广泛分布于各种组织,但是功能知之甚少。三叶因子在创伤修复与肿瘤发生中具有重要作用,其分子作用机制尚不清楚。非晶状体βγ晶状体蛋白与三叶因子蛋白复合物(βγ-CAT)是一个从大蹼铃蟾皮肤分泌物中分离的一类全新的蛋白复合物。研究表明,βγ-CAT能够诱导离体的兔胸主动脉产生快速而持续的收缩,结合药理学抑制剂,细胞培养,激光共聚焦显微镜和免疫荧光原位组化,从细胞和分子水平对其作用机制进行研究。结果表明:βγ-CAT诱导兔胸主动脉产生的收缩效应为剂量依赖(2—35nmol/L)和内皮依赖(P<0.01)。在βγ-CAT(25nmol/L)处理的主动脉环的内皮细胞层检测到肿瘤坏死因子-α的释放。同时,βγ-CAT能够诱导原代培养的兔胸主动脉内皮细胞(RAEC)快速释放肿瘤坏死因子-α,βγ-CAT(25nmol/L)分别处理5和30min,RAEC释放的肿瘤坏死因子-α的浓度分别为(34.17±5.10)pg/mL和(98.01±4.67)pg/mL(P<0.01)。表明肿瘤坏死因子-α在βγ-CAT诱导兔胸主动脉产生的收缩效应中发挥重要作用。为进一步深入研究非晶状体βγ晶状体蛋白与三叶因子的生理功能提供了新的思路和线索。
In vertebrates, non-lens βγ-crystallins are widely expressed in various tissues and their functions are not well known. The molecular mechanisms of trefoil factors （TFFs）, which involved in mucosal healing and tumorigenesis, have remained elusive. βγ-CAT is a novel multifunctional protein complex of non-lens βγ-crystallin and trefoil factor from frog skin secretions. Here we report that βγ-CAT could induce sustained contraction of isolated rabbit aortic rings in dosage （2-35nmol/L） and endothelium dependent manners （P〈0.01 ）. In addition, in situ immunofluorescence indicated that positive TNF-α signals were mainly detected at the endothelial cell layer of βγ-CAT （25nmol/L） treated rings. Furthermore, βγ-CAT induced primary cultured rabbit thoracic aortic endothelial cells （RAECs） rapidly to release TNF-α. After βγ-CAT （25nmol/L） treated for 10 and 30min, the levels of the endothelial cells released TNF-ct were 34.17±5.10 pg/mL and 98.01±4.67 pg/mL （P〈0.01）, respectively. In conclusion, βγ-CAT could induce sustained contraction of isolated aortic rings, and the contractile effect might be partially explained by the release of TNF-α. These findings will give new insight into understanding the functions and physiological roles of non-lens βγ-crystallins and trefoil factors.
基金
National Natural Science Foundation (30630014, 30570359)
The grant of "Key Research Direction-KSCX2-YW-R-088" from Chinese Academy of Sciences~~
