Dataset Information

Mammalian Cell Proliferation Requires Noncatalytic Functions of O-GlcNAc Transferase

ABSTRACT: O-GlcNAc transferase (OGT), found in the nucleus and cytoplasm of all mammalian cell types, is essential for cell proliferation. Why OGT is required for cell growth is not known. OGT performs two enzymatic reactions in the same active site. In one, it glycosylates thousands of different proteins, and in the other, it proteolytically cleaves another essential protein involved in gene expression. Deconvoluting OGT’s myriad cellular roles has been challenging because genetic deletion is lethal; complementation methods have not been established. Here, we developed approaches to replace endogenous OGT with separation-of-function variants to investigate the importance of OGT’s enzymatic activities for cell viability. Using genetic complementation, we found that OGT’s glycosyltransferase function is required for cell growth but its protease function is dispensable. We next used complementation to construct a cell line with degron-tagged wild-type OGT. When OGT was degraded to very low levels, cells stopped proliferating but remained viable. Adding back catalytically-inactive OGT rescued growth. Therefore, OGT has an essential noncatalytic role that is necessary for cell proliferation. By developing a method to quantify how OGT’s catalytic and noncatalytic activities affect protein abundance, we found that OGT’s noncatalytic functions often affect different proteins from its catalytic functions. Proteins involved in oxidative phosphorylation and the actin cytoskeleton were especially impacted by the noncatalytic functions. We conclude that OGT integrates both catalytic and noncatalytic functions to control cell physiology.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Joao Paulo

LAB HEAD: Joao A. Paulo

PROVIDER: PXD022654 | Pride | 2021-09-09

REPOSITORIES: pride

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	401619_a14578_Zeb_mou.mzIdentML	Mzid
	401620_a14577_Zeb_mou.mzIdentML	Mzid
	401621_a14576_Zeb_mou.mzIdentML	Mzid
	401622_a14575_Zeb_mou.mzIdentML	Mzid
	401623_a14574_Zeb_mou.mzIdentML	Mzid

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Mammalian cell proliferation requires noncatalytic functions of O-GlcNAc transferase.

Levine Zebulon G ZG Potter Sarah C SC Joiner Cassandra M CM Fei George Q GQ Nabet Behnam B Sonnett Matthew M Zachara Natasha E NE Gray Nathanael S NS Paulo Joao A JA Walker Suzanne S

Proceedings of the National Academy of Sciences of the United States of America 20210101 4

O-GlcNAc transferase (OGT), found in the nucleus and cytoplasm of all mammalian cell types, is essential for cell proliferation. Why OGT is required for cell growth is not known. OGT performs two enzymatic reactions in the same active site. In one, it glycosylates thousands of different proteins, and in the other, it proteolytically cleaves another essential protein involved in gene expression. Deconvoluting OGT's myriad cellular roles has been challenging because genetic deletion is lethal; com ...[more]

PMID: 33419956

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