Cloning and isolation of a conus cysteine-rich protein homologous to Tex31 but without proteolytic activity  

作　　者：Jing Qian Zhan-yun Guo Cheng-wu Chi 

机构地区：[1]Institute of Protein Research, Tongji University, Shanghai 200092, China [2]Institute of Biochemistry and Ceil'Biology, Shanghai Institutes forBiological Sciences, Chinese Academy of Sciences, Shanghai 200031, China

出　　处：《Acta Biochimica et Biophysica Sinica》2008年第2期174-181,共8页生物化学与生物物理学报（英文版）

摘　　要：We cloned and isolated a cysteine-rich protein, designated Mr30, from Conus marmoreus. Mr30 belongs to the cysteinerich secretory protein family that is highly homologous to Tex31 previously obtained from Conus textile and reported as a protease responsible for processing of pro-conotoxins. Mr30, purified by a procedure similar to that of Tex31, indeed showed low proteolytic activity. However, further investigations revealed that the detected protease activity actually resulted from a trace amount of protease（s） con- tamination rather than from Mr30 itself. This finding led us to rethink the role of conus cysteine-rich secretory proteins： they were probably not responsible for the processing of pro-conotoxins as previously deduced, but their real biological functions remained to be clarified.We cloned and isolated a cysteine-rich protein, designated Mr30, from Conus marmoreus. Mr30 belongs to the cysteinerich secretory protein family that is highly homologous to Tex31 previously obtained from Conus textile and reported as a protease responsible for processing of pro-conotoxins. Mr30, purified by a procedure similar to that of Tex31, indeed showed low proteolytic activity. However, further investigations revealed that the detected protease activity actually resulted from a trace amount of protease（s） con- tamination rather than from Mr30 itself. This finding led us to rethink the role of conus cysteine-rich secretory proteins： they were probably not responsible for the processing of pro-conotoxins as previously deduced, but their real biological functions remained to be clarified.

关 键 词：cone snail cysteine-rich secretory protein PROTEASE protease inhibitor covalent modification 

分 类 号：Q5[生物学—生物化学]