Author/Editor		Molt, Sibylle; Bührdel, John B.; Yakovlev, Sergiy; Schein, Peter; Orfanos, Zacharias; Kirfel, Gregor; Winter, Lilli; Wiche, Gerhard
Title		Aciculin interacts with filamin C and Xin and is essential formyofibril assembly, remodeling and maintenance
Type		članek
Vol. and No.		, št. Vol. 127
Publication year		2014
Volume		str. 3578-3592
ISSN		0021-9533 - Journal of cell science
Language		eng
Abstract		Filamin C (FLNc) and Xin actin-binding repeat-containing proteins(XIRPs) are multi-adaptor proteins that are mainly expressed in cardiac and skeletal muscles and which play important roles in the assembly and repair of myofibrils and their attachment to the membrane. We identified the dystrophin-binding protein aciculin(also known as phosphoglucomutase-like protein 5, PGM5) as anew interaction partner of FLNc and Xin. All three proteins colocalized at intercalated discs of cardiac muscle and myotendinous junctions of skeletal muscle, whereas FLNc andaciculin also colocalized in mature Z-discs. Bimolecular fluorescence complementation experiments in developing culture dmammalian skeletal muscle cells demonstrated that Xin and aciculin also interact in FLNc-containing immature myofibrils and areas of myofibrillar remodeling and repair induced by electrical pulse stimulation (EPS). Fluorescence recovery after photobleaching (FRAP) experiments showed that aciculin is ahighly dynamic and mobile protein. Aciculin knockdown in myotubesled to failure in myofibril assembly, alignment and membrane attachment, and a massive reduction in myofibril number. A highly similar phenotype was found upon depletion of aciculin in zebrafish embryos. Our results point to a thus far unappreciated, but essential, function of aciculin in myofibril formation, maintenance and remodeling.
Keywords		myofibrillogenesis phosphoglucomutase striated muscle miofibrilogeneza fosfoglukomutaza progaste mišice