Characterization of human skeletal muscle Ankrd2

Human Ankrd2 transcript encodes a 37-kDa protein that is similar to mouse A nkrd2 recently shown to be involved in hypertrophy of skeletal muscle. Thes e novel ankyrin-rich proteins are related to C-193/CARP/MARP, a cardiac pro tein involved in the control of cardiac hypertrophy. A human genomic region of 14,300 bp was sequenced revealing a gene organization similar to mouse Ankrd2 with nine exons, four of which encode ankyrin repeats. The intracell ular localization of Ankrd2 was unknown since no protein studies had been r eported. In this paper we studied the intracellular localization of the pro tein and its expression on differentiation using polyclonal and monoclonal antibodies produced to human Ankrd2. In adult skeletal muscle Ankrd2 is fou nd in slow fibers; however, not all of the slow fibers express Ankrd2 at th e same level. This is particularly evident in dystrophic muscles, where the expression of Ankrd2 in slow fibers seems to be severely reduced. (C) 2001 Academic Press.