Worm Breeder's Gazette 7(2): 18
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
We have sought to identify minor structural proteins of C. elegans muscle with the eventual aim of characterizing genes encoding them. For this purpose, antibodies are being raised to minor bands present in extracts of broken cuticles with muscle fibrils still attached, prepared by limited French press shearing and repeated low-speed sedimentations in low ionic strength buffer containing nonionic detergent. By polarizing and electron microscopy the bodywall musculature remains associated with the cuticle through this treatment without gross structural alterations while nuclei and other cytoplasmic constituents are washed away. Of the antisera prepared so far, the most interesting is a rabbit antibody to a 107,000 MW protein which by indirect immunofluorescence stains the dense-bodies of the bodywall musculature [the dense bodies serve as thin filament anchors analogous to the z-disc of vertebrate skeletal muscle]. As this protein cross-reacts with an antibody to smooth muscle alpha-actinin ( a component of smooth muscle dense-bodies) on nitrocellulose replicas of SDS-gels we presume it to be an alpha-actinin-like protein and are doing further experiments to test homology. Antibodies to other purified polypeptides appear to recognize intermediate filaments or hypodermal cell structures limited to areas beneath the bodywall musculature that may be responsible for transmitting muscle tension to the cuticle. Finally, an antibody to a 230,000 MW polypeptide lights up the nervous system circuitry: nerve ring, head neurons, dorsal and ventral cords, commisures, etc. Although this antigen is uncharacterized, it could be the macromolecule recognized by peanut agglutinin which, by lectin fluorescence, is present in the broken and washed cuticles. Currently mutants are being screened with these antibodies by immunofluorescence and two-dimensional electrophoresis but as yet we have no gene-protein correlations.