Muscle type-specific expression of Zasp52 isoforms in Drosophila

Department of Biology, McGill University, 1205 Dr. Penfield Avenue, Montreal, Quebec, Canada H3A 1B1.
Gene Expression Patterns (Impact Factor: 1.36). 08/2011; 11(8):484-90. DOI: 10.1016/j.gep.2011.08.004
Source: PubMed

ABSTRACT Zasp52 is a member of the PDZ-LIM domain protein family in Drosophila, which comprises Enigma, ENH, ZASP, Alp, CLP36, RIL, and Mystique in vertebrates. Drosophila Zasp52 colocalizes with integrins at myotendinous junctions and with α-actinin at Z-disks, and is required for muscle attachment as well as Z-disk assembly and maintenance. Here we document 13 Zasp52 splice variants giving rise to six different LIM domains. We demonstrate stage- and tissue-specific expression in different muscle types for Zasp52 isoforms encoding different LIM domains. In particular, LIM1b is expressed only in heart muscle and certain somatic muscles, implying muscle-specific functions in Z-disk assembly or maintenance.

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