title: 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.
authors.affiliation: Department of Biomolecular Chemistry 271, Nijmegen Center for Molecular Life Sciences, Radboud University, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Guido
authors.initials: G
authors.lastname: Kappé
authors.forename: Wilbert C
authors.initials: WC
authors.lastname: Boelens
authors.forename: Wilfried W
authors.initials: WW
authors.lastname: de Jong
mesh_terms: D000595:Amino Acid Sequence; D050888:Heat-Shock Proteins, Small / Q000145:classification*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000145:classification*; D016415:Sequence Alignment; D009626:Terminology as Topic; D038201:alpha-Crystallins / Q000737:chemistry
chemical_list: C525841:HSPB11 protein, human; D050888:Heat-Shock Proteins, Small; D047908:Intracellular Signaling Peptides and Proteins; D011506:Proteins; D038201:alpha-Crystallins