Identification and intracellular localization of the unc-22 gene product of Caenorhabditis elegans.
The unc-22 gene is one of a set of genes identified using classical genetics that affect muscle structure and function in the free-living nematode Caenorhabditis elegans. Since cloning the unc-22 gene by transposon tagging, we have used conventional techniques combined with a set of Tc1 transposon insertion alleles to characterize the gene and its products. The gene extends over more than 20 kb of genomic sequence and produces a transcript of approximately 14 kb. A polyclonal antibody raised against an Escherichia coli beta-galactosidase-unc-22 fusion protein recognizes a polypeptide in nematode extracts that is between 500,000 and 600,000 daltons and labels the muscle A-band in indirect immunofluorescent microscopy. The Tc1-induced alleles have been used at every stage to verify these conclusions. The Tc1 insertions are spread over much of the region that contributes to the mature transcript; in most alleles, Tc1 sequences are incorporated into a composite unc-22-Tc1 transcript. The large protein is either absent or severely reduced in amounts in the mutants. In one case, a truncated polypeptide was also identified. The location of the protein in the A-band, along with earlier genetic data, suggests that the unc-22 product may interact with myosin to regulate its function.
Moerman
D G
DG
Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110.
Benian
G M
GM
Barstead
R J
RJ
Schriefer
L A
LA
Waterston
R H
RH
D000818:Animals; D002107:Caenorhabditis / Q000235:genetics*; D002451:Cell Compartmentation; D004251:DNA Transposable Elements; D005455:Fluorescent Antibody Technique; D007163:Immunosorbent Techniques; D008970:Molecular Weight; D009124:Muscle Proteins / Q000235:genetics* / Q000502:physiology; D009132:Muscles / Q000502:physiology* / Q000648:ultrastructure; D009154:Mutation; D009218:Myosins / Q000378:metabolism; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics
D004251:DNA Transposable Elements; D009124:Muscle Proteins; D012333:RNA, Messenger; D009218:Myosins