CPNA-1, a copine domain protein, is located at integrin adhesion sites and is required for myofilament stability in Caenorhabditis elegans

Adam Warner, Ge Xiong, Hiroshi Qadota, Teresa Rogalski, A. Wayne Vogl, Donald G. Moerman, Guy M. Benian

Research output: Contribution to journalArticle

18 Scopus citations


We identify cpna-1 (F31D5.3) as a novel essential muscle gene in the nematode Caenorhabditis elegans. Antibodies specific to copine domain protein atypical-1 (CPNA-1), as well as a yellow fluorescent protein translational fusion, are localized to integrin attachment sites (M-lines and dense bodies) in the body-wall muscle of C. elegans. CPNA-1 contains an N-terminal predicted transmembrane domain and a C-terminal copine domain and binds to the M-line/dense body protein PAT-6 (actopaxin) and the M-line proteins UNC-89 (obscurin), LIM-9 (FHL), SCPL-1 (SCP), and UNC-96. Proper CPNA-1 localization is dependent upon PAT-6 in embryonic and adult muscle. Nematodes lacking cpna-1 arrest elongation at the twofold stage of embryogenesis and display disruption of the myofilament lattice. The thick-filament component myosin heavy chain MYO-3 and the M-line component UNC-89 are initially localized properly in cpna-1-null embryos. However, in these embryos, when contraction begins, MYO-3 and UNC-89 become mislocalized into large foci and animals die. We propose that CPNA-1 acts as a linker between an integrin-associated protein, PAT-6, and membrane-distal components of integrin adhesion complexes in the muscle of C. elegans.

Original languageEnglish (US)
Pages (from-to)601-616
Number of pages16
JournalMolecular biology of the cell
Issue number5
StatePublished - Mar 1 2013
Externally publishedYes


ASJC Scopus subject areas

  • Molecular Biology
  • Cell Biology

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