Paramyosin gene (unc-15) of Caenorhabditis elegans

Kagawa, Hiroaki; K, Gengyo; McLachlan, Anton; Brenner, Sydney; Karn, Jonathan

doi:10.1016/0022-2836(89)90257-x

Cited by 123 publications

(45 citation statements)

References 54 publications

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“…Paramyosin is important for formation of thick filaments and for their assembly into myofibrils (11,12). The zones of positive and negative charge on the ␣-helical region of paramyosin and their interaction with the myosin tail appear to play a key role in these processes (6,9,10,12).…”

Section: Table 2 Summary Of Isolated Ifm Isometric Datamentioning

confidence: 99%

“…For instance, this ratio is 1:34 in the fibrillar flight muscle of Drosophila melanogaster but is 1:6 in larval muscles (5). Sequence analysis of paramyosin isoforms isolated from different species reveal a rod-like molecule with a central ␣-helical region and two nonhelical terminal domains that can dimerize into a coiled-coil structure (6,7). Like the myosin tail, amino acids of the paramyosin helical region have a periodic 28-residue positive and negative charge repeat distribution (6,8).…”

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confidence: 99%

“…Sequence analysis of paramyosin isoforms isolated from different species reveal a rod-like molecule with a central ␣-helical region and two nonhelical terminal domains that can dimerize into a coiled-coil structure (6,7). Like the myosin tail, amino acids of the paramyosin helical region have a periodic 28-residue positive and negative charge repeat distribution (6,8). This charge arrangement on the surfaces of paramyosin and the myosin tail may regulate the packing of these two proteins in the thick filament (6,9,10).…”

mentioning

confidence: 99%

“…Like the myosin tail, amino acids of the paramyosin helical region have a periodic 28-residue positive and negative charge repeat distribution (6,8). This charge arrangement on the surfaces of paramyosin and the myosin tail may regulate the packing of these two proteins in the thick filament (6,9,10).…”

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confidence: 99%

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Paramyosin phosphorylation site disruption affects indirect flight muscle stiffness and power generation in Drosophila melanogaster

Liu

Miller

Swank

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

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The phosphoprotein paramyosin is a major structural component of invertebrate muscle thick filaments. To investigate the importance of paramyosin phosphorylation, we produced transgenic Drosophila melanogaster in which one, three, or four phosphorylatable serine residues in the N-terminal nonhelical domain were replaced by alanines. Depending on the residues mutated, transgenic lines were either unaffected or severely flight impaired. Flight-impaired strains had decreases in the most acidic paramyosin isoforms, with a corresponding increase in more basic isoforms. Surprisingly, ultrastructure of indirect flight muscle myofibrils was normal, indicating N-terminal phosphorylation is not important for myofibril assembly. However, mechanical studies of active indirect flight muscle fibers revealed that phosphorylation site mutations reduced elastic and viscous moduli by 21-59% and maximum power output by up to 42%. Significant reductions also occurred under relaxed and rigor conditions, indicating that the phosphorylation-dependent changes are independent of strong crossbridge attachment and likely arise from alterations in thick filament backbone properties. Further, normal crossbridge kinetics were observed, demonstrating that myosin motor function is unaffected in the mutants. We conclude that N-terminal phosphorylation of Drosophila paramyosin is essential for optimal force and oscillatory power transduction within the muscle fiber and is key to the high passive stiffness of asynchronous insect flight muscles. Phosphorylation may reinforce interactions between myosin rod domains, enhance thick filament connections to the central M-line of the sarcomere and͞or stabilize thick filament interactions with proteins that contribute to fiber stiffness.contraction ͉ thick filament ͉ sarcomere ͉ mechanics ͉ insect P aramyosin is a major structural component of thick filaments in invertebrate muscle. The paramyosin to myosin ratio, which positively correlates with thick filament length and maximum active tension development (1), varies widely between different invertebrate phyla and even between different muscles within the same animal (2-5). For instance, this ratio is 1:34 in the fibrillar flight muscle of Drosophila melanogaster but is 1:6 in larval muscles (5). Sequence analysis of paramyosin isoforms isolated from different species reveal a rod-like molecule with a central ␣-helical region and two nonhelical terminal domains that can dimerize into a coiled-coil structure (6, 7). Like the myosin tail, amino acids of the paramyosin helical region have a periodic 28-residue positive and negative charge repeat distribution (6,8). This charge arrangement on the surfaces of paramyosin and the myosin tail may regulate the packing of these two proteins in the thick filament (6, 9, 10).Paramyosin is important for thick filament formation and for filament assembly into myofibrils (11,12). A currently accepted model of invertebrate thick filament assembly is that paramyosin molecules, together with other thick filament structur...

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Section: Table 2 Summary Of Isolated Ifm Isometric Datamentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

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Paramyosin phosphorylation site disruption affects indirect flight muscle stiffness and power generation in Drosophila melanogaster

Liu

Miller

Swank

et al. 2005

Proc. Natl. Acad. Sci. U.S.A.

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“…In nematode adult body wall muscle, thick filaments are ϳ10 m long and are composed primarily of myosin heavy chain A (MHC A), myosin heavy chain B (MHC B), and paramyosin, encoded by the genes myo -3, unc-54, and unc-15, respectively (Epstein et al, 1974;Miller et al, 1983;Kagawa et al, 1989). Within each thick filament these components are differentially localized: MHC A is in the middle of the thick filament and MHC B is in the polar regions (Miller et al, 1983).…”

Section: Introductionmentioning

confidence: 99%

UNC-98 and UNC-96 Interact with Paramyosin to Promote Its Incorporation into Thick Filaments ofCaenorhabditis elegans

Miller

Qadota

Mercer

et al. 2008

MBoC

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Mutations in unc-96 or -98 cause reduced motility and a characteristic defect in muscle structure: by polarized light microscopy birefringent needles are found at the ends of muscle cells. Anti-paramyosin stains the needles in unc-96 and -98 mutant muscle. However there is no difference in the overall level of paramyosin in wild-type, unc-96, and -98 animals. Anti-UNC-98 and anti-paramyosin colocalize in the paramyosin accumulations of missense alleles of unc-15 (encodes paramyosin). Anti-UNC-96 and anti-UNC-98 have diffuse localization within muscles of unc-15 null mutants. By immunoblot, in the absence of paramyosin, UNC-98 is diminished, whereas in paramyosin missense mutants, UNC-98 is increased. unc-98 and -15 or unc-96 and -15 interact genetically either as double heterozygotes or as double homozygotes. By yeast two-hybrid assay and ELISAs using purified proteins, UNC-98 interacts with paramyosin residues 31-693, whereas UNC-96 interacts with a separate region of paramyosin, residues 699-798. The importance of surface charge of this 99 residue region for UNC-96 binding was shown. Paramyosin lacking the C-terminal UNC-96 binding region fails to localize throughout A-bands. We propose a model in which UNC-98 and -96 may act as chaperones to promote the incorporation of paramyosin into thick filaments.

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Complete amino acid sequence ofMytilus anterior byssus retractor paramyosin and its putative phosphorylation site

et al. 2000

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A cDNA encoding the full‐length paramyosin molecule was cloned from the mussel Mytilus galloprovincialis, a species closely related to Mytilus edulis. It contained 3,497 nucleotides (nt), with 79 and 826 nt for the 5′ and 3′ non‐coding regions, respectively. The coding region was composed of 2,592 nt for 864 amino acid residues, a size typical of paramyosin. While genomic DNA digests with either HindIII or PstI exhibited a single band when hybridized with a SacI fragment of paramyosin cDNA, the digests with either EcoRV or EcoRI showed two bands, suggesting that the mussel has at least two genes encoding paramyosin. The mRNAs encoding paramyosin were most abundant in muscle tissues from byssus retractor and adductor muscles. Only traces of paramyosin transcripts were found in the tissue of foot, gill, inner mantle, and outer mantle. The same phosphorylatable peptide previously reported for paramyosin from the bivalve Mercenaria mercenaria, Ser‐Arg‐Ser‐Met‐Ser(P)‐Val‐Ser‐Arg (Watabe et al. 1989. Comp Biochem Physiol 94B:813–821) was found in the C‐terminal non‐helical part of this Mytilus paramyosin. We predict that this particular paramyosin has a coiled‐coil structure composed of two α‐helices that show the heptad repeats (a‐b‐c‐d‐e‐f‐g) with further 28‐amino acid repeat zones, where a and d tend to be occupied by nonpolar residues. J. Exp. Zool. 286:24–35, 2000.© 2000 Wiley‐Liss, Inc.

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Paramyosin gene (unc-15) of Caenorhabditis elegans

Cited by 123 publications

References 54 publications

Paramyosin phosphorylation site disruption affects indirect flight muscle stiffness and power generation in Drosophila melanogaster

Paramyosin phosphorylation site disruption affects indirect flight muscle stiffness and power generation in Drosophila melanogaster

UNC-98 and UNC-96 Interact with Paramyosin to Promote Its Incorporation into Thick Filaments ofCaenorhabditis elegans

Complete amino acid sequence ofMytilus anterior byssus retractor paramyosin and its putative phosphorylation site

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