Nakashima Shigeru
Department of Biochemistry, Gifu University School of Medicine, Tsukasamachi 40, Gifu 500-8705.
J Biochem. 2002 Nov;132(5):669-75. doi: 10.1093/oxfordjournals.jbchem.a003272.
Protein kinase C alpha (PKC alpha) is a serine/threonine kinase and a member of the conventional (classical) PKCs (cPKCs), which have four conserved (C1 to C4) regions. This ubiquitously expressed PKC isotype is activated in response to many different kinds of stimuli and translocates from cytosol to the specialized cellular compartments (nucleus, focal adhesion, caveolae, etc.) where it is presumed to work. Therefore, PKC alpha has been implicated in a variety of cellular functions including proliferation, apoptosis, differentiation, motility, and inflammation. However, the responses induced by activation or overexpression of PKC alpha vary depending on the types, and sometimes conditions, of cells. For example, in some types of cells, PKC alpha is implicated in cell growth. In contrast, it may play a role in cell cycle arrest and differentiation in other types of cells. Therefore, alterations of cell responses induced by PKC alpha are not an intrinsic property of this isoform. The responses are modulated by dynamic interactions with cell-type specific factors: substrates, modulators and anchoring proteins.
蛋白激酶Cα（PKCα）是一种丝氨酸/苏氨酸激酶，属于传统（经典）蛋白激酶C（cPKC）家族，该家族有四个保守区域（C1至C4）。这种广泛表达的PKC亚型可响应多种不同刺激而被激活，并从细胞质转位至特定的细胞区室（细胞核、黏着斑、小窝等），据推测它在这些区室发挥作用。因此，PKCα参与了多种细胞功能，包括增殖、凋亡、分化、迁移和炎症。然而，PKCα激活或过表达所诱导的反应因细胞类型以及有时因细胞状态而异。例如，在某些类型的细胞中，PKCα参与细胞生长。相反，它可能在其他类型的细胞的细胞周期阻滞和分化中发挥作用。因此，PKCα诱导的细胞反应改变并非该亚型的固有特性。这些反应通过与细胞类型特异性因子（底物、调节剂和锚定蛋白）的动态相互作用而受到调节。
