Functional expression and molecular characterization of AtUBC2-1, a novel ubiquitin-conjugating enzyme (E2) from Arabidopsis thaliana

Plant Mol Biol. 1993 Oct;23(2):387-96. doi: 10.1007/BF00029013.


The first member of a novel subfamily of ubiquitin-conjugating E2-proteins was cloned from a cDNA library of Arabidopsis thaliana. Genomic blots indicate that this gene family (AtUBC2) consists of two members and is distinct from AtUBC1, the only other E2 enzyme known from this species to date (M.L. Sullivan and R.D. Vierstra, Proc. Natl. Acad. Sci. USA 86 (1989) 9861-9865). The cDNA sequence of AtUBC2-1 extends over 794 bp which would encode a protein of 161 amino acids and a calculated molecular mass of 18.25 kDa. The protein encoded by AtUBC2-1 is shown to accept 125I-ubiquitin from wheat E1 enzymes, when expressed from Escherichia coli hosts as fusion protein carrying N-terminal extensions. It is deubiquitinated in the presence of lysine and, by these criteria, is considered a functional E2 enzyme.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / enzymology
  • Arabidopsis / genetics*
  • Base Sequence
  • DNA, Complementary / genetics
  • Escherichia coli / genetics
  • Ligases / biosynthesis
  • Ligases / genetics*
  • Ligases / metabolism
  • Molecular Sequence Data
  • Multigene Family
  • Protein Conformation
  • Recombinant Fusion Proteins / biosynthesis
  • Restriction Mapping
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Triticum / enzymology
  • Ubiquitin-Conjugating Enzymes
  • Ubiquitin-Protein Ligases


  • DNA, Complementary
  • Recombinant Fusion Proteins
  • Ubiquitin-Conjugating Enzymes
  • Ubiquitin-Protein Ligases
  • Ligases

Associated data

  • GENBANK/X68306