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Volume 393, Issue 1 p. 113-116
Research letter
Free Access

Attenuated function of a variant form of the helix-loop-helix protein, Id-3, generated by an alternative splicing mechanism

Richard W. Deed

Corresponding Author

Richard W. Deed

CRC Department of Gene Regulation, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 9BX, UK

Corresponding author. Fax: (44) (0161) 446 3109.Search for more papers by this author
Michelle Jasiok

Michelle Jasiok

CRC Department of Gene Regulation, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 9BX, UK

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John D. Norton

John D. Norton

CRC Department of Gene Regulation, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 9BX, UK

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First published: September 09, 1996
Citations: 23

Abstract

The Id family of helix-loop-helix proteins function as negative regulators of DNA binding, basic helix-loop-helix proteins in the regulation of cell growth and differentiation. We report here on the identification of a 17 kDa variant of the 14 kDa Id-3 protein termed Id-3L (long version) which possesses a unique 60 amino acid carboxy-terminus generated by readthrough of a ‘coding intron’ and alternative splicing. Northern analysis revealed expression of a minor 1.1 kb Id-3L transcript together with the predominant 0.95 kd Id-3 transcript in the majority of adult human tissues analysed. The variant Id-3L protein is functionally distinguishable from conventional Id-3 since in in vitro DNA mobility shift assays, it was greatly impaired in its ability to abrogate binding of the basic helix-loop-helix protein, E47, to an E box recognition sequence.