Functional Properties of a Recombinant Striated α-Tropomyosin Mutant That Amino Acid Residue 282 Was Replaced with Cysteine from Threonine

다국어 초록 (Multilingual Abstract)

We have constructed a mutant striated tropomyosin (TM), TM16C, which a cysteine residue was introduced to amino acid residue 282 for the purpose of chemical modification studies. The carboxyl terminal sequence of TM16C was ^(282)CNM^(284) and rest of the sequence was identical to the striated tropomyosin. The mutant tropomyosin was overproduced in Escherichia soli and was purified near to homogeneity. Unlike striated and TM16, TM16C failed to crosslink by 5,5'-dithio-bis(2-nitrobenzoic acid). This result might suggest that the carboxyl terminal region of tropomyosin be not in a coiled coil configuration. TM16C bound to actin well whereas striated TM and TMC1903 bound hardly to actin. Strong actin binding ability of TM16C makes this mutant an ideal model for understanding the nature of actin-tropomyosin interaction by chemical modification studies.

목차 (Table of Contents)

• Contents
• Abstract
• Introduction
• Materials and Methods
• Construction of mutant tropomyosin
• Isolation and Purification of mutant tropomyosins
• Actin binding assay
• Crosslinking by 5,5'-dithio-bis (2-nitrobenzoic acid)
• Results and Discussion
• Acknowledgement
• References