Developmentally Regulated Post-translational Modification of Nucleoplasmin Controls Histone Sequestration and Deposition.

ABSTRACT: Nucleoplasmin (Npm) is an abundant histone chaperone in vertebrate oocytes and embryos. During embryogenesis, regulation of Npm histone binding is critical for its function in storing and releasing maternal histones to establish and maintain the zygotic epigenome. Here, we demonstrate that Xenopus laevis Npm post-translational modifications (PTMs) specific to the oocyte and egg promote either histone deposition or sequestration, respectively. Mass spectrometry and Npm phosphomimetic mutations used in chromatin assembly assays identified hyperphosphorylation on the N-terminal tail as a critical regulator for sequestration. C-terminal tail phosphorylation and PRMT5-catalyzed arginine methylation enhance nucleosome assembly by promoting histone interaction with the second acidic tract of Npm.

SUBMITTER: Onikubo T 

PROVIDER: S-EPMC4567554 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature