Alla Kostyukova, Kayo Maeda, Emiko Yamauchi, Hisaaki Taniguchi, Yuichiro Maeda
1999 Seibutsu Butsuri  
UniverSIty Tropomodulin ( Tmod ) , a 40 kDa protein , is expressed in many tissues including muscles and it is the only known P −cnd capping protein of ac 面 丘laments ( Fowler , 1987; Weber ot aL , 1994 ) . Aocordlng to literatUre the C− t巳 inal half of Tmod may be involved in the P−end capping , although no ev 言 dじnce fbr direct interaction betweじn th工 s part and actin has been pr 巳 sented . On the other h d the N − tenninal half 量 s responsib 隻 e fc 〕 r 亡 he tTopornyosin binding . As a part of
more » ... Qur sear じh fbr a goQd tool sGrving ft 〕r preparing sh 。 rt segment Qf actin −tropomyosin 撫 ment of 跚 un 迂 b「m legth , we have been studying Tmed . Firsdy , good expression systems have been es餓 blished for chicken muscle Tmod . ESp 巳 cially the variant that lacks 15amino acids at its original C −terminus ( ヒ he tmncated Tmod ) is advantageous . Compared to the completc molccule , the tnmcated Tmod binds to actin − tropQmyosin equally well , while it is less susceptible to prQteDlysis . In the present s加 dy, therefbre , the 且 oo μ expressed tmncated Tmod has been used . Secondly , the doma孟 n s恤 c加 re has becn s加 died , Limited proteolysis , mass −spec 訂oscopy and nea τ 一 as weU as far UV CD have 貢 ndlcated that Tmod is an α 一 helix rich pro し ein and consists of two distinot pa 質 s 、 The C 一 し erminal ha 至 f ( 2D kDa )fbrms a 亡 1ght domaln which is tesistant to protcolysis and can bc oas 藍 1y p 磁 置ed . In contrast , the N −terminal half】 ikely has poorly definite te買 iary s鰤 c 財 e . Limited prQ [ eolysis has indicated that , upon binding to actin − tropomyos 重 n , the N ・ terminal half of Tmod beじomes less susceptible to proteolysls , This may be acceumted for either by transition into a more tightly folded con { b ation , er by protection by actin andfor tropomyosin 3PBOI6
doi:10.2142/biophys.39.s188_3 fatcat:dxsgexft3rc7xbidme5obzvuzy