人亲环素18抑制肌酸激酶的去折叠

新生肽链折叠过程中容易出现错误折叠与聚沉，从而导致折叠病等病理现象. 分子伴侣具有辅助其他蛋白质正确折叠，保护蛋白质分子结构的功能.本文选用人肌肌酸激酶为靶蛋白，研究了肽基脯氨酰顺反异构酶人亲环素18（human cyclophilin 18，hCyp18）对人肌肌酸激酶去折叠的作用，发现hCyp18能够抑制人肌肌酸激酶在热变性与化学变性过程中的失活与构象变化，并抑制人肌肌酸激酶在化学变性过程中的聚沉，因此推断hCyp18具有针对人肌肌酸激酶的分子伴侣功能.本文同时研究了hCyp18与人肌肌酸激酶的结合作用，对hCyp18的作用机制进行了初步探讨.

Inhibitory Effect of Human Cyclophilin 18 on Unfolding of Creatine Kinase

The inefficient folding of polypeptide chains in vitro or in vivo may lead to misfolded conformation formation or protein aggregation.A number of human diseases,known as protein-misfolding diseases,have been found with misfolding of proteins.The molecular chaperones are a group of proteins which can assist in the folding of their interacted proteins and stabilize the native structure of proteins or prevent misfolding.We evaluated the influence of human cyclophilin 18(hCyp18) on the unfolding of human muscle creatine kinase(HMCK).hCyp18 was found to inhibit heat or guanidine-induced inactivation of HMCK and conformational change.HMCK aggregation induced by guanidine was reduced.The binding of hCyp18 and HMCK was observed.These findings demonstrated that hCyp18 exerted chaperone-like activities to attenuate the denaturation of HMCK and inhibit its aggregation.