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Heat shock protein 27 (Hsp27) also known as heat shock protein beta-1 (HSPB1) is a protein that in humans is encoded by the ''HSPB1'' gene. Hsp27 is a chaperone of the sHsp (small heat shock protein) group among ubiquitin, α-crystallin, Hsp20 and others. The common functions of sHsps are chaperone activity, thermotolerance, inhibition of apoptosis, regulation of cell development, and cell differentiation. They also take part in signal transduction. == Structure == sHsps have some structural features in common: Very characteristic is a homologous and highly conserved amino acid sequence, the so-called α-crystallin-domain at the C-terminus. These sequences consist of 80 to 100 residues with a homology between 20% and 60% and form β-sheets, which are important for the formation of stable dimers. The N-terminus consists of a less conserved region, the so-called WD/EPF domain, followed by a short variable sequence with a rather conservative site near the C-terminus of this domain. The C-terminal part of the sHsps consists of the above mentioned α-crystallin domain, followed by a variable sequence with high motility and flexibility. This C-terminal tail appears in many mammalian sHsps (e.g. mouse Hsp25, αA-crystallin) and has no homology. It is highly flexible and polar because of its negative charges. Probably it functions as a mediator of solubility for hydrophobic sHsps and it stabilizes the protein and protein/substrate complexes. This was shown by elimination of the C-terminal tail in Hsp27Δ182-205 and in Hsp25Δ18. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Hsp27」の詳細全文を読む スポンサード リンク
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