RRC ID 46296
Author Nahabedian JF, Qadota H, Stirman JN, Lu H, Benian GM.
Title Bending amplitude - a new quantitative assay of C. elegans locomotion: identification of phenotypes for mutants in genes encoding muscle focal adhesion components.
Journal Methods
Abstract The nematode Caenorhabditis elegans uses striated muscle in its body wall for locomotion. The myofilament lattice is organized such that all the thin filament attachment structures (dense bodies, analogous to Z-disks) and thick filament organizing centers (M-lines) are attached to the muscle cell membrane. Thus, the force of muscle contraction is transmitted through these structures and allows locomotion of the worm. Dense bodies and M-lines are compositionally similar to focal adhesions and costameres, and are based on integrin and associated proteins. Null mutants for many of the newly discovered dense body and M-line proteins do not have obvious locomotion defects when observed casually, or when assayed by counting the number of times a worm moves back and forth in liquid. We hypothesized that many of these proteins, located as they are in muscle focal adhesions, function in force transmission, but we had not used an appropriate or sufficiently sensitive assay to reveal this function. Recently, we have developed a new quantitative assay of C. elegans locomotion that measures the maximum bending amplitude of an adult worm as it moves backwards. The assay had been used to reveal locomotion defects for null mutants of genes encoding ATN-1 (α-actinin) and PKN-1 (protein kinase N). Here, we describe the details of this method, and apply it to 21 loss of function mutants in 17 additional genes, most of which encode components of muscle attachment structures. As compared to wild type, mutants in 11 genes were found to have less ability to bend, and mutants in one gene were found to have greater ability to bend. Loss of function mutants for eight proteins had been reported to have normal locomotion (ZYX-1 (zyxin), ALP-1 (Enigma), DIM-1, SCPL-1), or locomotion that was not previously investigated (FRG-1 (FRG1), KIN-32 (focal adhesion kinase), LIM-8), or had only slightly decreased locomotion (PFN-3 (profilin)).
Volume 56(1)
Pages 95-102
Published 2012-1-1
DOI 10.1016/j.ymeth.2011.11.005
PII S1046-2023(11)00237-4
PMID 22126736
PMC PMC3299906
MeSH Animals Caenorhabditis elegans* / genetics Caenorhabditis elegans* / metabolism Caenorhabditis elegans Proteins* / genetics Caenorhabditis elegans Proteins* / metabolism Focal Adhesions / genetics Focal Adhesions / physiology* Locomotion / genetics Monitoring, Physiologic / methods* Mutation* Phenotype
IF 3.812
Times Cited 24
C.elegans tm752 tm1362