Dataset Information

The UBA-domain of Ubc1/Ube2K Facilitates the Assembly of K48-/K63-Branched Ubiquitin Chains

ABSTRACT: Assembly of polymeric ubiquitin (Ub) chains is an essential posttranslational protein modification that regulates widespread intracellular processes in eukaryotic cells. Factors and mechanisms that regulate the formation of Ub chains are key to the understanding of many cellular processes. The E2 enzyme Ubc1 (Ube2K) exclusively targets K48 in Ub for chain formation and has been linked to cell-cycle progression and proteostasis. Uniquely among E2 enzymes, it harbors a Ub binding UBA domain, which has been implicated in Ub chain formation but its function remained elusive. Through in vitro binding experiments, we unexpectedly found that the UBA domain enables preferential binding of K63-linked Ub chains. Based on structural modeling, extensive in vitro ubiquitination experiments and NMR binding studies, we propose a mechanism through which Ubc1 selectively forms K48/K63 branched Ub chains – an usual chain architecture, about whose prevalence and function little is known to date. Ultimately, we link UBA dependent activity of Ubc1 to its role in proteostasis through genetic experiments.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

TISSUE(S): Cell Suspension Culture

SUBMITTER: Henrik Zauber

LAB HEAD: Matthias Selbach

PROVIDER: PXD018651 | Pride | 2021-09-09

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	Animal_20200122_HZ_SC_PRM_brUbiLP_A_Lys8_r2.raw	Raw
	Animal_20200122_HZ_SC_PRM_brUbiLP_B_Lys8_r2.raw	Raw
	Animal_20200206_HZ_SC_PRM_brUbiLP_mutated_A_Lys8_1.raw	Raw
	Animal_20200206_HZ_SC_PRM_brUbiLP_mutated_B_Lys8_1.raw	Raw
	Statler_20170306_CHS_Lukas_Ubiquitin.raw	Raw

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Publications

The UBA domain of conjugating enzyme Ubc1/Ube2K facilitates assembly of K48/K63-branched ubiquitin chains.

Pluska Lukas L Jarosch Ernst E Zauber Henrik H Kniss Andreas A Waltho Anita A Bagola Katrin K von Delbrück Maximilian M Löhr Frank F Schulman Brenda A BA Selbach Matthias M Dötsch Volker V Sommer Thomas T

The EMBO journal 20210212 6

The assembly of a specific polymeric ubiquitin chain on a target protein is a key event in the regulation of numerous cellular processes. Yet, the mechanisms that govern the selective synthesis of particular polyubiquitin signals remain enigmatic. The homologous ubiquitin-conjugating (E2) enzymes Ubc1 (budding yeast) and Ube2K (mammals) exclusively generate polyubiquitin linked through lysine 48 (K48). Uniquely among E2 enzymes, Ubc1 and Ube2K harbor a ubiquitin-binding UBA domain with unknown f ...[more]

PMID: 33576509

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