Structural component of the muscle thick filaments which is involved in assembly and organization of sarcomere myofilaments (PubMed:2754728, PubMed:27009202). Involved in ovulation (PubMed:17326220). Plays a role in the formation of muscle connections, also called muscle arm extensions, between the body wall and the motor axons in the dorsal and ventral cord (PubMed:27123983). Homodimer (Probable). May interact with unc-89 (via SH3 domain) (PubMed:27009202). Localizes in punctate patterns along the myosin heavy chain myo-3 filaments in myoepithelial sheath cells. Expressed in body wall muscles of larvae and adults (at protein level) (PubMed:27009202). Expressed in gonadal myoepithelial sheath cells (at protein level) (PubMed:17326220). For most of its length, paramyosin appears to form an alpha-helical coiled coil and shows the heptad repeat of hydrophobic amino acid residues and the 28-residue repeat of charged amino acids characteristic of myosin heavy chains. However, paramyosin differs from myosin in having non-helical extensions at both termini and an additional 'skip' residue that interrupts the 28-residue repeat. The distribution of charged residues is also different from myosin heavy chains. Phosphorylated on serine residues in the N-terminal non-helical region. Defective extension of body wall muscle connections or arms towards the ventral nerve cord (PubMed:27123983). Double knockout with madd-3 results in severe muscle arm extension defects (PubMed:27123983). RNAi-mediated knockdown causes an accumulation in the proximal gonad of endomitotic mature oocytes in 22 percent of animals (PubMed:17326220). Belongs to the paramyosin family.