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Why proteins without an alpha-crystallin domain should not be included in the human small heat shock protein family HSPB.

ABSTRACT: The presence of an alpha-crystallin domain documents the evolutionary relatedness of the ubiquitous family of small heat shock proteins. Sequence and three-dimensional structure provide no evidence for the presence of such a domain in HSPC034, recently proposed as the 11th member of the human HSPB family. Also, phylogenetic analyses detect no relationship between HSPC034 and the human HSPB1-10 sequences. Arguments are provided as to why inclusion in the HSPB family of proteins like HSPC034, which resemble small heat shock proteins in being heat-inducible and having chaperone-like properties and a low monomeric mass, but are evolutionarily unrelated, is misleading and confusing.

SUBMITTER: Kappe G

PROVIDER: S-EPMC3082639 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Why proteins without an alpha-crystallin domain should not be included in the human small heat shock protein family HSPB.

Kappé Guido G Boelens Wilbert C WC de Jong Wilfried W WW

Cell stress & chaperones 20091118 4

The presence of an alpha-crystallin domain documents the evolutionary relatedness of the ubiquitous family of small heat shock proteins. Sequence and three-dimensional structure provide no evidence for the presence of such a domain in HSPC034, recently proposed as the 11th member of the human HSPB family. Also, phylogenetic analyses detect no relationship between HSPC034 and the human HSPB1-10 sequences. Arguments are provided as to why inclusion in the HSPB family of proteins like HSPC034, whic ...[more]

PMID: 19921466

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The human genome encodes 10 alpha-crystallin-related small heat shock proteins: HspB1-10.

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Oligomerization and chaperone-like activity of Drosophila melanogaster small heat shock protein DmHsp27 and three arginine mutants in the alpha-crystallin domain.

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