Two putative protein kinases from Arabidopsis thaliana contain highly acidic domains

Plant Mol Biol. 1993 Jul;22(4):615-24. doi: 10.1007/BF00047402.


Two cDNA clones (ASK1 and ASK2) for plant protein kinases were cloned from Arabidopsis thaliana by screening cDNA libraries with a degenerate oligonucleotide probe that corresponds to a highly conserved motif among protein kinases. Sequence analysis shows that the clones contain open reading frames that encode 41.2 kDa (ASK1) and 40.1 kDa (ASK2) proteins, respectively. These coding regions contain all the conserved motifs of protein kinases. Structural analysis of the coding regions revealed that the two protein kinase genes share high sequence similarity to each other (76.6% identity). The catalytic domain located in the amino terminal region is most similar to the calcium/calmodulin-dependent protein kinase subfamily (47.2% to 54.2% similarity) and the SNF1 kinase subfamily (48.1% to 53.3% similarity). However, the carboxy terminal regions contain distinctive stretches of 21 (ASK1) and 19 (ASK2) acidic amino acids. These clones are the first report of protein kinases with such acidic amino acid regions. The transcripts of both genes are most abundant in leaf but are also expressed in other organs. The expression of the two genes is highly affected by light regime.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics*
  • Base Sequence
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Cloning, Molecular
  • Genes, Plant / genetics*
  • Molecular Sequence Data
  • Plant Proteins / biosynthesis
  • Plant Proteins / genetics*
  • Protein Conformation
  • Protein Kinases / genetics
  • Protein-Serine-Threonine Kinases / biosynthesis
  • Protein-Serine-Threonine Kinases / genetics*
  • RNA, Messenger / genetics
  • Recombinant Proteins / biosynthesis
  • Sequence Analysis
  • Sequence Homology, Amino Acid
  • Tissue Distribution


  • Plant Proteins
  • RNA, Messenger
  • Recombinant Proteins
  • Protein Kinases
  • SNF1-related protein kinases
  • Protein-Serine-Threonine Kinases
  • Calcium-Calmodulin-Dependent Protein Kinases

Associated data

  • GENBANK/M91548
  • GENBANK/Z12120