Journal of Molecular Biology
Volume 180, Issue 3, 15 December 1984, Pages 457-472
Journal home page for Journal of Molecular Biology

Bovine β-crystallin complementary DNA clones: Alternating proline/alanine sequence of βB1 subunit originates from a repetitive DNA sequence

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Abstract

A library of recombinant plasmids carrying complementary DNA sequences synthesized from bovine lens messenger RNAs was constructed. Clones coding for five different β-crystallin subunits: βB1, βB3, βBp, βs, βA3 (and βA1), were identified by means of hybridization selection, followed by one- and two-dimensional gel electrophoresis of the translational products. Under rather stringent conditions each of these clones hybridizes with its corresponding mRNA and does not show significant cross-hybridization with mRNAs coding for other β-crystallins, except in the case of the homologous βA3 and βA1-crystalline. The βA3 and βA1 subunits seem to be encoded by one mRNA using two different AUG codons as start position for translation. We have also determined the nucleotide sequence of a βB1-crystallin cDNA (pBLβB1) which enabled us to deduce the complete amino acid sequence of the protein. The βB1-crystallin, a characteristic component of the high molecular weight crystallin aggregate (βH), is internally homologous both at DNA and protein level as has been reported for γ-and other β-crystallins. This is in agreement with the idea that these proteins had a common ancestral precursor gene that internally duplicated. The G + C content of the coding sequence of βB1 is very high: 67% overall and even 84.2% for the first 170 nucleotides, due to a remarkable non-random codon usage. A proline/ alanine repetition in the N-terminal domain of the protein is encoded by a repetitive “simple” DNA sequence.

References (43)

  • G.A.M. Berbers et al.

    FEBS Letters

    (1983)
  • H. Bloemendal et al.

    Exp. Eye Res.

    (1982)
  • J.L. Bos et al.

    Cell

    (1981)
  • H.P.C. Driessen et al.

    Exp. Eye Res.

    (1980)
  • J.J. Harding et al.

    Exp. Eye Res.

    (1976)
  • J.F. Hejtmancik et al.

    J. Biol. Chem.

    (1983)
  • G. Inana et al.

    J. Biol. Chem.

    (1982)
  • S.L. Peacock et al.

    Biochim. Biophys. Acta

    (1981)
  • F. Sanger et al.

    J. Mol. Biol.

    (1980)
  • C. Slingsby et al.

    Exp. Eye Res.

    (1978)
  • M.P. Wickens et al.

    J. Biol. Chem.

    (1978)
  • G. Wistow et al.

    FEBS Letters

    (1981)
  • G.A.M. Berbers et al.

    Eur. J. Biochem.

    (1982)
  • G.A.M. Berbers et al.

    Eur. J. Biochem.

    (1984)
  • H. Bloemendal

    Science

    (1977)
  • H. Bloemendal
  • H. Bloemendal et al.

    Documenta Ophtal.

    (1976)
  • T. Blundell et al.

    Nature (London)

    (1981)
  • L.H. Cohen et al.

    Eur. J. Biochem.

    (1978)
  • L.R. Croft

    Biochem. J.

    (1972)
  • H.P.C. Driessen et al.

    Eur. J. Biochem.

    (1981)
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    The present investigations have been carried out in part under the auspices of the Netherlands Foundation for Chemical Research (SON) and with financial aid of the Netherlands Organization for the Advancement of Pure Research (ZWO).

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