cDNA cloning, DNA binding, and evolution of mammalian transcription factor IIIA

Gene. 2002 Jan 9;282(1-2):43-52. doi: 10.1016/s0378-1119(01)00796-x.


cDNA for rat transcription factor IIIA (TFIIIA) was cloned by degenerate PCR and rapid amplification of cDNA ends. This cDNA coded for a protein with nine Cys(2)His(2) zinc fingers and a non-finger C-terminal tail; 63% amino acid (aa) sequence identity was observed with the Xenopus TFIIIA zinc finger region. Recombinant rat protein containing only the nine fingers afforded DNase I protection of the identical nucleotides protected by Xenopus laevis native TFIIIA on the Xenopus 5S RNA gene internal control region. A putative mouse TFIIIA clone was identified in an expressed sequence tag database by sequence similarity to rat TFIIIA. Recombinant nine-finger protein from this clone afforded DNase I protection of the Xenopus 5S rRNA gene like the native frog protein as did a recombinant nine-finger form of a putative human TFIIIA clone. These DNA binding results demonstrate that these clones code for the respective mammalian TFIIIAs. Rodent and human TFIIIAs share about 87% aa sequence identity in their zinc finger regions and have evolved to about the same extent as X. laevis and Xenopus borealis TFIIIAs. A monoclonal antibody against human p53 tumor suppressor bound to rat and mouse TFIIIA but not to human TFIIIA in Western blots. The N-terminal regions of rodent and human TFIIIA do not contain the oocyte-specific initiating Met and accompanying conserved residues found in fish and amphibian TFIIIAs. In their non-finger C-terminal tails, mammalian and amphibian TFIIIAs share a conserved transcription activation domain as well as conserved nuclear localization and nuclear export signals.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA, Complementary / chemistry
  • DNA, Complementary / genetics
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Evolution, Molecular*
  • Gene Expression
  • Humans
  • Mice
  • Molecular Sequence Data
  • Protein Binding
  • Rats
  • Rats, Inbred WF
  • Rats, Sprague-Dawley
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Transcription Factor TFIIIA
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism


  • DNA, Complementary
  • DNA-Binding Proteins
  • Recombinant Proteins
  • Transcription Factor TFIIIA
  • Transcription Factors

Associated data

  • GENBANK/AF391798
  • GENBANK/AF391799