The Sole Essential Low Molecular Weight Tropomyosin Isoform of Caenorhabditis Elegans is Essential For Pharyngeal Muscle Function.

Details

• Alternative Title:
  Cytoskeleton (Hoboken, N.J.), 2025, v. 82, no. 12: The Sole Essential Low Molecular Weight Tropomyosin Isoform of Caenorhabditis Elegans is Essential For Pharyngeal Muscle Function.
• Journal Article:
  Cytoskeleton (Hoboken, N.J.)
• Personal Author:
  Kimmich, Michael J. ; Geary, Meaghan A. ; Mi-Mi, Lei ; Votra, SarahBeth D. ; Pellenz, Christopher D. ; Sundaramurthy, Sumana ; Pruyne, David
• Description:
  Tropomyosin is an actin-binding protein that plays roles ranging from regulating muscle contraction to controlling cytokinesis and cell migration. The simple nematode Caenorhabditis elegans provides a useful model for studying the core functions of tropomyosin in an animal, having a relatively simple anatomy and a single tropomyosin gene, lev-11, that produces seven isoforms. Three higher molecular weight isoforms regulate the contraction of body wall and other muscles, but comparatively less is known of the functions of four lower molecular weight isoforms (LEV-11C, E, T, U). We demonstrate here that C. elegans can survive with a single low molecular weight isoform, LEV-11E. Mutants disrupted for LEV-11E die as young larvae, whereas mutants lacking all other short isoforms are viable, with no overt phenotype. Vertebrate low molecular weight tropomyosins are often considered "nonmuscle" isoforms, but we find LEV-11E localizes to sarcomeric thin filaments in pharyngeal muscle and co-precipitates from worm extracts with the formin FHOD-1, which is also associated with thin filaments in pharyngeal muscle. Pharyngeal sarcomere organization is grossly normal in larvae lacking LEV-11E, indicating that the tropomyosin is not required to stabilize thin filaments, but pharyngeal pumping is absent, suggesting LEV-11E regulates actomyosin activity similar to higher molecular weight sarcomeric tropomyosin isoforms.
• Content Notes:
  Author manuscript
• Subjects:
  • Animals
  • Tropomyosin
  • Caenorhabditis elegans
  • Protein Isoforms
  • Caenorhabditis elegans Proteins
  • Pharyngeal Muscles
  • Molecular Weight
  • Sarcomeres
• Keywords:
  • actin
  • sarcomere
  • tropomyosin
  • muscle
  • C. elegans
• Source:
  Cytoskeleton (Hoboken, N.J.), 2025, v. 82, no. 12
• DOI:
  https://doi.org/10.1002/cm.22014
• ISSN:
  1949-3584 ; 1949-3592
• Pubmed ID:
  40078096
• Pubmed Central ID:
  PMC12353527
• Document Type:
  Text
• Funding:
  P40 OD010440/CD/ODCDC CDC HHSUnited States/ ; P40 OD010440/OD/NIH HHSUnited States/ ; 102234/WT_/Wellcome TrustUnited Kingdom/ ; R01AR064760/AR/NIAMS NIH HHSUnited States/ ; R01 AR064760/AR/NIAMS NIH HHSUnited States/ ; 102234/WT_/Wellcome TrustUnited Kingdom/ ; R01AR064760/AR/NIAMS NIH HHSUnited States/ ; P40 OD010440/CD/ODCDC CDC HHSUnited States/
• Genre:
  Journal Article
• Pages in Document:
  815-836 (40 pdf pages)
• Volume:
  82
• Issue:
  12
• Download URL:
  https://stacks.cdc.gov/view/cdc/261602/cdc_261602_DS1.pdf
• File Type:
  [PDF - 3.46 MB]
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha-512:c20e66e954185267eb7f34108049c5e4b5a857a39cb043397265c29b8fda4773528187ea01b61fce9fb86571e4e61ab52c0992af4c6ab8ceb684ba45055d7f87