Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, USA.
Front Immunol. 2012 Jul 11;3:197. doi: 10.3389/fimmu.2012.00197. eCollection 2012.
Protein kinase C (PKC)-θ is a serine/threonine kinase belonging to the calcium-independent novel PKC subfamily; its expression is restricted to certain tissues and cell types, including T cells. The signals delivered from T cell receptor (TCR) and CD28 costimulatory molecules trigger PKC-θ catalytic activation and membrane translocation to the immunological synapse, leading to activation of NF-κB, AP-1, and NF-AT. These transcription factors are important for T cell survival, activation, and differentiation. Phosphorylation of PKC-θ at multiple Ser/Thr/Tyr residues is induced in T cells during TCR signaling. Some phosphorylation sites play critical roles in the regulation of PKC-θ function and downstream signaling. The regulation mechanisms for PKC-θ phosphorylation sites are now being revealed. In this review, we discuss the current understanding of the regulation of PKC-θ function by phosphorylation during TCR signaling.
蛋白激酶 C（PKC）-θ 是一种丝氨酸/苏氨酸激酶，属于钙非依赖性新型 PKC 亚家族；其表达局限于某些组织和细胞类型，包括 T 细胞。T 细胞受体（TCR）和 CD28 共刺激分子传递的信号触发 PKC-θ 催化激活和膜易位到免疫突触，导致 NF-κB、AP-1 和 NF-AT 的激活。这些转录因子对于 T 细胞的存活、激活和分化非常重要。在 TCR 信号转导过程中，T 细胞中 PKC-θ 的多个 Ser/Thr/Tyr 残基发生磷酸化。一些磷酸化位点在调节 PKC-θ 功能和下游信号转导中发挥关键作用。PKC-θ 磷酸化位点的调节机制正在被揭示。在这篇综述中，我们讨论了目前对 TCR 信号转导过程中 PKC-θ 功能通过磷酸化调节的理解。
