TY - JOUR A1 - Wiesner, Sebastian A1 - Salmikangas, Paula A1 - Auerbach, Daniel A1 - Himmel, Mirko A1 - Kempa, Stefan A1 - Hayes, Kathrin A1 - Pacholsky, Dirk A1 - Taivainen, Anu A1 - Schröder, Rolf A1 - Carpen, Olli A1 - Fürst, Dieter Oswald T1 - Indications for a novel muscular dystrophy pathway : gamma-filamin, the muscle-specific filamin isoform, intgeracts with myotilin Y1 - 2000 ER - TY - JOUR A1 - Vorgerd, M. A1 - vanderVen, Peter F. M. A1 - Bruchertseifer, V. A1 - Lowe, T. A1 - Kley, R. A. A1 - Schröder, Rolf A1 - Lochmuller, H. A1 - Himmel, Mirko A1 - Koehler, K. A1 - Fürst, Dieter Oswald A1 - Huebner, A. T1 - A mutation in the dimerization domain of filamin C causes a novel type of autosomal dominant myofibrillar myopathy N2 - Myofibrillar myopathy (MFM) is a human disease that is characterized by focal myofibrillar destruction and pathological cytoplasmic protein aggregations. In an extended German pedigree with a novel form of MFM characterized by clinical features of a limb-girdle myopathy and morphological features of MFM, we identified a cosegregating, heterozygous nonsense mutation (8130G -> A; W2710X) in the filamin c gene ( FLNC) on chromosome 7q32.1. The mutation is the first found in FLNC and is localized in the dimerization domain of filamin c. Functional studies showed that, in the truncated mutant protein, this domain has a disturbed secondary structure that leads to the inability to dimerize properly. As a consequence of this malfunction, the muscle fibers of our patients display massive cytoplasmic aggregates containing filamin c and several Z-disk-associated and sarcolemmal proteins Y1 - 2005 SN - 0002-9297 ER - TY - JOUR A1 - Pacholsky, Dirk A1 - Vakeel, Padmanabhan A1 - Himmel, Mirko A1 - Lowe, T. A1 - Stradal, T. A1 - Rottner, K. A1 - Fürst, Dieter Oswald A1 - vanderVen, Peter F. M. T1 - Xin repeats define a novel actin-binding motif N2 - Xin is a protein that is expressed during early developmental stages of cardiac and skeletal muscles. Immunolocalization studies indicated a peripheral localization in embryonic mouse heart, where Xin localizes with beta- catenin and N-cadherin. In adult tissues, Xin is found primarily in the intercalated discs of cardiomyocytes and the myotendinous junctions of skeletal muscle cells, both specialized attachment sites of the myofibrillar ends to the sarcolemma. A large part of the Xin protein consists of unique 16 amino acid repeats with unknown function. We have investigated the characteristics of the Xin repeats by transfection experiments and actin-binding assays and ascertained that, upon expression in cultured cells, these repeats bind to and stabilize the actin-based cytoskeleton. In vitro co- sedimentation assays with skeletal muscle actin indicated that they not only directly bind actin filaments, but also have the capability of arranging microfilaments into networks that sediment upon low-speed centrifugation. Very similar repeats were also found in Xin-repeat protein 2' (XIRP2), a novel protein that seems to be expressed mainly in striated muscles. Human XIRP2 contains 28 Xin repeats with properties identical to those of Xin. We conclude that the Xin repeats define a novel, repetitive actin-binding motif present in at least two different muscle proteins. These Xin- repeat proteins therefore constitute the first two members of a novel family of actin-binding proteins Y1 - 2004 SN - 0021-9533 ER - TY - JOUR A1 - Lange, Stephan A1 - Himmel, Mirko A1 - Auerbach, Daniel A1 - Agarkova, Irina A1 - Hayess, Katrin A1 - Fürst, Dieter Oswald A1 - Perriard, Jean-Claude A1 - Ehler, Elisabeth T1 - Dimerisation of myomesin : implications for the structure of the sarcomeric M-band N2 - The sarcomeric M-band is thought to provide a link between the thick and the elastic, filament systems. So far, relatively little is known about its structural components and their three-dimensional organisation. Myomesin seems to be an essential component of the M-band, since it is expressed in all types of vertebrate striated muscle fibres investigated and can be found in its mature localisation pattern as soon as the first myofibrils are assembled. Previous work has shown that the N-terminal and central part of myomesin harbour binding sites for myosin, titin and muscle creatine kinase. Intrigued by the highly conserved domain layout of the C-terminal half, we screened for new interaction partners by yeast two-hybrid analysis. This revealed a strong interaction of myomesin with itself. This finding was confirmed by several biochemical assays. Our data suggest that myomesin can form antiparallel dimers via a binding site residing in its C-terminal domain 13. We suggest that, similar to alpha-actinin in the Z-disc, the myomesin dimers cross- link the contractile filaments in the M-band. The new and the already previously identified myomesin interaction sites are integrated into the first three-dimensional model of the sarcomeric M-band on a molecular basis. (C) 2004 Elsevier Ltd. All rights reserved Y1 - 2005 SN - 0022-2836 ER - TY - JOUR A1 - Himmel, Mirko A1 - VanderVen, Peter F. M. A1 - Stöcklein, Walter F. M. A1 - Fürst, Dieter Oswald T1 - The limits of promiscuity : isoform-specific dimerization of filamins Y1 - 2003 ER -