Journal of Molecular Evolution

, Volume 34, Issue 1, pp 45–53 | Cite as

Exons encoding the highly conserved part of human glutaminyl-tRNA synthetase

  • Eva Kaiser
  • Dirk Eberhard
  • Rolf Knippers


Aminoacyl-tRNA synthetases are important components of the genetic apparatus. In spite of common catalytic properties, synthetases with different amino acid specificities are widely diverse in their primary structures, subunit sizes, and subunit composition. However, synthetases with given amino acid specificities are well conserved throughout evolution. We have been studying the human glutaminyl-tRNA synthetase possessing a sequence of about 400 amino acid residues (the core region) that is very similar to sequences in the corresponding enzymes from bacteria and yeast. The conserved sequence appears to be essential for the basic function of the enzyme, the charging of tRNA with glutamine. As a first step to a better understanding of the evolution of this enzyme, we determined the coding region for the conserved part of the human glutaminyl-tRNA synthetase. The coding region is composed of eight exons. It appears that individual exons encode defined secondary structural elements as parts of functionally important domains of the enzyme. Evolution of the gene by assembly of individual exons seems to be a viable hypothesis; alternative pathways are discussed.

Key words

Aminoacyl-tRNA synthetases Human glutaminyl-tRNA synthetase Exon Secondary structure elements Functional domains Core region 


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Copyright information

© Springer-Verlag New York Inc 1992

Authors and Affiliations

  • Eva Kaiser
    • 1
  • Dirk Eberhard
    • 2
  • Rolf Knippers
    • 1
  1. 1.Fakultät für BiologieUniversität KonstanzKonstanzGermany
  2. 2.Deutsches Krebsforschungszentrum Im Neuenheimer FeldHeidelbergGermany

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