摘要
Onconase是从美洲豹蛙卵中提取的一种核糖核酸酶,由于其抗肿瘤活性而具有潜在的临床应用价值。以中国林蛙基因组为模板,克隆了一个新的RNase基因,并由此推导出了成熟林蛙RNase的氨基酸顺序。该酶是由103个氨基酸残基组成的,它保留了RNase A家族成员酶催化活性必须的组氨酸和赖氨酸残基,以及CKXXNTF的序列特征,与Onconase具有73%的氨基酸顺序的相似性。林蛙酶比Onconase少一个氨基酸,成为迄今为止发现的RNaseA家族中的最小成员;并且,林蛙酶拥有的精氨酸和酪氨酸残基比Onconase多3个。此外,在利用原核表达系统对林蛙RNase基因进行表达的过程中,表达产物对宿主显示出一定的细胞毒性。
Onconase,a member of ribonuclease A superfamily,was isolated from oocytes of Rana pipiens,which showed perspective of application in clinic due to its antitumor activity.In this study,a novel ribonuclease gene from the genomic DNA of Rana dybowskii was isolated.The sequence analysis demonstrated that it consists of 103 amino acid residues in mature enzyme,and shows 73% amino acid identity to Onconase,but one less amino acid residue than Onconase,which makes it the smallest member found in the superfamily.The enzyme also included 3 more positively charged amino acid residues than Onconase.Furthermore,during the expression with prokaryotic system,the recombinant showed the cytotoxic activity to the host.All results above indicate that the enzyme may become a potent antitumor biological agent.
出处
《生物技术通报》
CAS
CSCD
北大核心
2011年第10期130-134,共5页
Biotechnology Bulletin
基金
北京市教育委员会科技发展计划面上项目(KM200411417014)
