Identification of a human cDNA encoding a novel protein kinase with two repeats of the LIM/double zinc finger motif

Kensaku Mizuno, Ichiro Okano, Kazumasa Ohashi, Koh Nunoue, Kei Ichi Kuma, Takashi Miyata, Toshikazu Nakamura

Research output: Contribution to journalArticlepeer-review

166 Citations (Scopus)


By low-stringency screening of a human hepatoma HepG2 cell cDNA library, using the genomic fragment of chick c-sea receptor tyrosine kinase as a probe, we isolated overlapping cDNAs encoding a novel protein kinase, which we termed LIM-kinase (LIMK).(*) The predicted open reading frame encodes a 647-amino-acid polypeptide containing a putative protein kinase structure in the C-terminal half. In addition, LIMK has two repeats of cysteine-rich LIM/double zinc finger motif at the most N-terminus. To our knowledge, this is the first protein kinase seen to contain the LIM motif(s) in the molecule. Although the protein kinase domain of LIMK has highly conserved sequence elements of protein kinases, phylogenetic analysis revealed that LIMK cannot be classified into any subfamily of known protein kinases. Northern blot analysis revealed that the single species of LIMK mRNA of 3.3 kb was expressed in various human epithelial and hematopoietic cell lines. In rat tissues, LIMK mRNA was expressed in the brain, at the highest level. LIM is suggested to be involved in protein-protein interactions by binding to another LIM motif. As the LIM domain is frequently present in the homeodomain-containing transcriptional regulators and oncogenic nuclear proteins, LIMK may be involved in developmental or oncogenic processes through interactions with these LIM-containing proteins.

Original languageEnglish
Pages (from-to)1605-1612
Number of pages8
Issue number6
Publication statusPublished - 1994 Jun 1
Externally publishedYes

ASJC Scopus subject areas

  • Molecular Biology
  • Genetics
  • Cancer Research


Dive into the research topics of 'Identification of a human cDNA encoding a novel protein kinase with two repeats of the LIM/double zinc finger motif'. Together they form a unique fingerprint.

Cite this