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Chinese Science Bulletin

, Volume 45, Issue 22, pp 2034–2041 | Cite as

Cloning, expression and mapping of the full-length cDNA of human CCTβ subunit

  • Juxiang Jiang
  • Wei Lin
  • Honglai Zhang
  • Zheng Chen
  • Qiang Tu
  • Ying Jiang
  • Long Yu
  • Shouyuan Zhao
Papers

Abstract

Chaperonins assist the proper folding of target proteins without being a part of the substrates. The eukaryotic cytosolic chaperonin, CCT-Chaperonin Containing TCP-1 (tailless complex polypeptide-1), is mainly involved in the formation of cytoskeletal proteins and is essential for cell viability. Mammalian CCT is commonly a protein complex composed of 7–9 subunit species. We have isolated a novel full-length cDNA from human testis cDNA library. This cDNA of 1935 bp contains a 1605 bp open reading frame (ORF) encoding 535 amino acids (aa). The deduced protein of the cDNA is highly homologous to the CCTβ subunit ofsaccharomyces cerevisiae,schizosaccharomyces pombe, caenorhabditis elegans and mouse, etc. Especially high homology (97%) is found between the deduced protein and mouse CCTβ. On the basis of such high homology, the protein encoded by the new gene was proposed to be a human CCTβ subunit. Northern hybridization showed that humanCCTβ gene is expressed as a transcript of about 2.0 kb in various tissues. Overexpression was seen in testis with the expression level 3–24 times of those in other tissues. TheCCTβ gene was mapped to human chromosome 12q14 by Radiation Hybrid Mapping. Through homologous search, the 5′-end of the cDNA sequence was found to share intermittent regional homology with the 3′-end of human genomic sequence (U91327).The genomic structure of the 5′-end ofCCTβ was also described in detail through comparative analysis.

Keywords

CCTβ subunit cDNA cloning tissue expression pattern human chromosome 12q14 

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Copyright information

© Science in China Press 2000

Authors and Affiliations

  • Juxiang Jiang
    • 1
    • 2
  • Wei Lin
    • 1
  • Honglai Zhang
    • 1
  • Zheng Chen
    • 2
  • Qiang Tu
    • 1
  • Ying Jiang
    • 2
  • Long Yu
    • 1
  • Shouyuan Zhao
    • 1
  1. 1.State Key Laboratory of Genetic Engineering, Institute of Genetics. School of Life ScienceFudan UniversityShanghaiChina
  2. 2.Department of Biochemistry, College of Medical ScienceSuzhou UniversitySuzhouChina

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