Muscle M-line assembly protein unc-89

UniProtKB accession:  O01761

Grouped By:  Matching UniProtKB accession

UniProtKB description:  Structural component of the muscle M line which is involved in assembly and organization of sarcomere myofilaments (PubMed:15313609, PubMed:16453163, PubMed:18801371, PubMed:22621901, PubMed:23283987, PubMed:27009202). The large isoform a, isoform b, isoform d and isoform f play an essential role in maintaining the organization of sarcomeres but not myofilament alignment during body wall muscle development whereas the small isoform c and isoform d appear to have a minor role (PubMed:15313609, PubMed:16453163, PubMed:22768340). Isoform b and isoform f are required for the organization of unc-15/paramyosin into sarcomere thick filaments in body wall muscles (PubMed:27009202). By binding mel-26, a substrate adapter of the cul-3 E3 ubiquitin-protein ligase complex, regulates the organization of myosin thick filaments, likely by preventing the degradation of microtubule severing protein mei-1 (PubMed:22621901). Acts as a guanine nucleotide exchange factor (GEF) for Rho GTPase rho-1 but not ced-10, mig-2 and cdc-42 (PubMed:18801371). The large isoforms regulate Ca(2+) signaling during muscle contraction by ensuring the correct localization of sarco-endoplamic reticulum Ca(2+) ATPase sca-1 and ryanodine receptor unc-68 (PubMed:22768340). By controlling the contraction and/or organization of pharyngeal muscles, plays a role in the formation of pharyngeal gland cell extension (PubMed:21868609).