Hspb1
Function
Small heat shock protein which functions as a molecular chaperone probably maintaining denatured proteins in a folding-competent state. Plays a role in stress resistance and actin organization (PubMed:17661394). Through its molecular chaperone activity may regulate numerous biological processes including the phosphorylation and the axonal transport of neurofilament proteins (By similarity).
Post-translational modifications
Phosphorylated upon exposure to protein kinase C activators and heat shock (By similarity). Phosphorylation by MAPKAPK2 and MAPKAPK3 in response to stress dissociates HSPB1 from large small heat-shock protein (sHsps) oligomers and impairs its chaperone activity and ability to protect against oxidative stress effectively. Phosphorylation by MAPKAPK5 in response to PKA stimulation induces F-actin rearrangement (PubMed:1332886, PubMed:1860870, PubMed:21575178, PubMed:8093612).
Sequence Similarities
Belongs to the small heat shock protein (HSP20) family.
Cellular localization
- Cytoplasm
- Nucleus
- Cytoplasm
- Cytoskeleton
- Spindle
- Cytoplasmic in interphase cells. Colocalizes with mitotic spindles in mitotic cells. Translocates to the nucleus during heat shock and resides in sub-nuclear structures known as SC35 speckles or nuclear splicing speckles.
Alternative names
Hsp25, Hsp27, Hspb1, Heat shock protein beta-1, HspB1, Growth-related 25 kDa protein, Heat shock 25 kDa protein, Heat shock 27 kDa protein, p25, HSP 25, HSP 27