Alpha-crystallin/small heat shock protein has autokinase activity.
AUTOR(ES)
Kantorow, M
RESUMO
The alpha-crystallins (alpha A and alpha B) are major water-soluble proteins of the transparent eye lens that are expressed in a variety of tissues and can function as molecular chaperones. alpha B-crystallin is also a small heat shock protein associated with numerous degenerative diseases and abnormal growth patterns. Previous experiments have shown that alpha A-and alpha B-crystallin are phosphorylated on specific serine residues by a cAMP-dependent pathway. Here we provide evidence that either total bovine alpha-crystallin or its isolated polypeptides can autophosphorylate serine by a cAMP-independent mechanism in the presence of Mg2+ and [gamma-32P]ATP; the autophosphorylated products isoelectrically focus with the authentic phosphorylated forms of the alpha-crystallin polypeptides. Thus, the alpha A- and alpha B-crystallin/small heat shock protein polypeptides are enzyme-crystallins which may be involved in metabolic pathways important for the development, maintenance, or pathology of the lens and other tissues.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=43525Documentos Relacionados
- Alpha B-crystallin is a small heat shock protein.
- Regulation of the murine alpha B-crystallin/small heat shock protein gene in cardiac muscle.
- Structure and alternate tissue-preferred transcription initiation of the mouse alpha B-crystallin/small heat shock protein gene.
- Influence of trehalose on the molecular chaperone activity of p26, a small heat shock/α-crystallin protein
- The murine alpha B-crystallin/small heat shock protein enhancer: identification of alpha BE-1, alpha BE-2, alpha BE-3, and MRF control elements.