Caenorhabditis elegans unc-51 gene required for axonal elongation encodes a novel serine/threonine kinase.
Mutations in the unc-51 gene of the nematode Caenorhabditis elegans result in various abnormalities in axonal elongation and axonal structures. We cloned the unc-51 gene by tagging with the transposon Tc1. The wild-type unc-51 gene, which rescued the mutant phenotypes, encodes a novel serine/threonine kinase of 856 amino acids. Mutation sites were identified in the unc-51 gene of six mutants. A Lys-->Met mutation created in vitro in the kinase domain led to the loss of rescuing activity and was dominant negative, indicating that the kinase domain of Unc-51 is essential for the function. Expression of an unc-51/lacZ fusion gene was observed in many neurons at all stages. We propose that protein phosphorylation by the unc-51 product is important for axonal elongation and possibly for axonal guidance.
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
K
K
Ogura
C
C
Wicky
L
L
Magnenat
H
H
Tobler
I
I
Mori
F
F
Müller
Y
Y
Ohshima
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001369:Axons / Q000502:physiology / Q000648:ultrastructure; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017238:Genes, Helminth; D008969:Molecular Sequence Data; D009415:Nerve Net / Q000254:growth & development / Q000502:physiology; D017354:Point Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D016324:Sequence Tagged Sites
D004251:DNA Transposable Elements; D018076:DNA, Complementary; D018509:DNA, Helminth; D017346:Protein Serine-Threonine Kinases