jkk-1 and mek-1 regulate body movement coordination and response to heavy metals through jnk-1 in Caenorhabditis elegans Academic Article uri icon


MeSH Major

  • Caenorhabditis elegans
  • Caenorhabditis elegans Proteins
  • Helminth Proteins
  • Metals, Heavy
  • Mitogen-Activated Protein Kinase Kinases
  • Mitogen-Activated Protein Kinases
  • Protein Kinases
  • Protein-Serine-Threonine Kinases


  • Although in vitro evidence suggests two c-Jun N-terminal kinase (JNK) kinases, MKK4 and MKK7, transactivate JNK, in vivo confirmation is incomplete. In fact, JNK deficiency may differ from the composite deficiency of MKK4 and MKK7 in Drosophila and mice. Recently, the Caenorhabditis elegans homolog of human JNK, jnk-1, and two MKK-7s, mek-1 and jkk-1, were cloned. Here we characterize jnk-1, which encodes two isoforms JNK-1 alpha and JNK-1 beta. A null allele, jnk-1(gk7), yielded worms with defective body movement coordination and modest mechanosensory deficits. Similarly to jkk-1 mutants, elimination of GABAergic signals suppressed the jnk-1(gk7) locomotion defect. Like mek-1 nulls, jnk-1(gk7) showed copper and cadmium hypersensitivity. Conditional expression of JNK-1 isoforms rescued these defects, suggesting that they are not due to developmental errors. While jkk-1 or mek-1 inactivation mimicked jnk-1(gk7) locomotion and heavy metal stress defects, respectively, mkk-4 inactivation did not, but rather yielded defective egg laying. Our results delineate at least two different JNK pathways through jkk-1 and mek-1 in C.elegans, and define interaction between MKK7, but not MKK4, and JNK.

publication date

  • September 17, 2001



  • Academic Article



  • eng

PubMed Central ID

  • PMC125628

Digital Object Identifier (DOI)

  • 10.1093/emboj/20.18.5114

PubMed ID

  • 11566876

Additional Document Info

start page

  • 5114

end page

  • 28


  • 20


  • 18