Abstract:
The nuclear lamina serves important functions in the nucleus, providing structural support to the nuclear envelope and contributing to chromatin organization. The primary proteins that constitute the lamina are nuclear lamins whose functions are impacted by post-translational modifications, including phosphorylation by protein kinase C (PKC). While PKC-mediated lamin phosphorylation is important for nuclear envelope breakdown during mitosis, less is known about interphase roles for PKC in regulating nuclear structure. Here we show that overexpression of PKC ß, but not PKC α, increases the Lamin A/C mobile fraction in the nuclear envelope in HeLa cells without changing the overall structure of Lamin A/C and Lamin B1 within the nuclear lamina. Conversely, knockdown of PKC ß, but not PKC α, reduces the Lamin A/C mobile fraction. Thus, we demonstrate an isoform-specific role for PKC in regulating interphase Lamin A/C dynamics outside of mitosis.
摘要:
核层在核中发挥重要作用,为核膜提供结构支持并有助于染色质组织。构成薄层的主要蛋白质是核层蛋白,其功能受到翻译后修饰的影响。包括蛋白激酶C(PKC)的磷酸化。虽然PKC介导的层粘连蛋白磷酸化对于有丝分裂过程中的核包膜分解很重要,关于PKC在调节核结构中的相间作用知之甚少。在这里,我们显示PKCβ的过表达,但不是PKCα,增加HeLa细胞中核被膜中的LaminA/C移动分数,而不改变核层中LaminA/C和LaminB1的整体结构。相反,PKCβ的敲低,但不是PKCα,减少LaminA/C移动部分。因此,我们证明了PKC在调节有丝分裂外的相间LaminA/C动力学中的同工型特异性作用。