Dataset Information

The nucleolus functions as the compartment for histone 1 H2B protein degradation

ABSTRACT: Histones are the main components in chromatin organization, and the protein levels of histones significantly affect chromatin assembly. However, how the protein levels of histones are regulated, especially whether and how histones are degraded, is largely unclear. Here, we found that histone H2B is mainly degraded through the proteasome mediated pathway, and the lysine 120 site of H2B is essential for the K48-linked polyubiquitination and protein degradation of H2B. Moreover, our results further indicated that the degradation-impaired H2BK120R mutant shows an increased nucleolus localization, and inhibition of the proteasome results in an elevated nucleolus distribution of wild-type H2B, which is similar to that of H2BK120R mutants. More importantly, our in vitro data showed that only the nucleolus fractions can ubiquitinate and degrade the purified H2B, suggesting that the nucleolus, in addition to its canonical roles in the regulation of ribosome genesis and protein translation, is likely associated with H2B protein degradation. Therefore, these findings revealed a novel mechanism for the regulation of H2B protein degradation in which a nucleolus associated proteasome pathway is involved.

INSTRUMENT(S): timsTOF Pro

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: sheng li

LAB HEAD: Su chen

PROVIDER: PXD023415 | Pride | 2021-09-09

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	FA490LQ_Nucleo_1_Slot2-5_1_10357.d.zip	Other
	FA490LQ_Nucleo_1_mqpar.xml	Xml
	FA490LQ_Nucleo_1_txt.zip	Other
	FA490LQ_Nucleo_2_Slot2-6_1_10359.d.zip	Other
	FA490LQ_Nucleo_2_mqpar.xml	Xml

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Publications

The nucleolus functions as the compartment for histone H2B protein degradation.

Liu Yanping Y Wang Yufei Y Yang Lu L Sun Feng F Li Sheng S Wang Yequan Y Zhang Guo-An GA Dong Tingting T Zhang Lei-Lei LL Duan Wanglin W Zhang Xiaojun X Cui Wen W Chen Su S

iScience 20210302 4

Histones are main components of chromatin, and the protein levels of histones significantly affect chromatin assembly. However, how histone protein levels are regulated, especially whether and how histones are degraded, is largely unclear. Here, we found that histone H2B is mainly degraded through the proteasome-mediated pathway, and the lysine-120 site of H2B is essential for its K48-linked polyubiquitination and degradation. Moreover, the degradation-impaired H2BK120R mutant shows an increased ...[more]

PMID: 33796843

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