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Different obscurin isoforms localize to distinct sites at sarcomeres.

ABSTRACT: We used four antibodies to regions of obscurin isoforms A and B, encoded by the obscurin gene, to investigate the location of these proteins in skeletal myofibers at resting and stretched lengths. Obscurin A ( approximately 800 kDa) which was recognized by antibodies generated to the N-terminal, Rho-GEF, and the non-modular C-terminal domain that lacks the kinase-like domains, localizes at the level of the M-band. Obscurin B ( approximately 900 kDa) which has the N-terminal, Rho-GEF, and the C-terminal kinase-like domains, localizes at the level of the A/I junction. Additional isoforms, which lack one or more of these epitopes, are present at the Z-disk and Z/I junction.

SUBMITTER: Bowman AL

PROVIDER: S-EPMC1899168 | biostudies-other | 2007 Apr

REPOSITORIES: biostudies-other

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Different obscurin isoforms localize to distinct sites at sarcomeres.

Bowman Amber L AL Kontrogianni-Konstantopoulos Aikaterini A Hirsch Sara S SS Geisler Sarah B SB Gonzalez-Serratos Hugo H Russell Mark W MW Bloch Robert J RJ

FEBS letters 20070315 8

We used four antibodies to regions of obscurin isoforms A and B, encoded by the obscurin gene, to investigate the location of these proteins in skeletal myofibers at resting and stretched lengths. Obscurin A ( approximately 800 kDa) which was recognized by antibodies generated to the N-terminal, Rho-GEF, and the non-modular C-terminal domain that lacks the kinase-like domains, localizes at the level of the M-band. Obscurin B ( approximately 900 kDa) which has the N-terminal, Rho-GEF, and the C-t ...[more]

PMID: 17382936

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