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HDX-MS of the TRAMP Complex with tRNA

ABSTRACT: TRAMP is a eukaryotic protein complex with RNA helicase and polyadenylase activity that marks and delivers a variety of RNA substrates to the nuclear exosome for degradation. Prior work has characterized binding of Trf4 and Air2 to the helicase core of Mtr4 and the regulation of both enzymatic activities in TRAMP. Air2 contains a conserved sequence that is predicted to bind the arch domain of Mtr4, though this interface is dispensable for TRAMP formation. To understand the interactions of the Saccharomyces cerevisiae TRAMP complex and its interactions with RNA, we have applied hydrogen-deuterium exchange mass spectrometry. We demonstrate that Air2 simultaneously binds the helicase core and the fist of Mtr4 in solution, constraining the arch to a conformation ready to bind RNA. We characterize the previously unknown interactions of Trf4 and Air2 with RNA and show how interactions with substrates are altered in TRAMP, supporting a mechanistic model for the enhancement of Mtr4 activity in TRAMP.

INSTRUMENT(S): Synapt MS

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

SUBMITTER: Sheena D'Arcy

LAB HEAD: Sheena D'Arcy

PROVIDER: PXD053773 | Pride | 2024-12-11

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	20190128_PLGS.zip	Other
	20190131_nz_TRAMP_RNA.raw.zip	Raw
	20210516_PLGS.zip	Other
	20210520_NZ_TRAMP.raw.zip	Raw
	TRAMP_HDX_Summary_Table.xlsx	Xlsx

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