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Stress-induced MazF-mediated proteins in Escherichia coli

ABSTRACT: Escherichia coli (E. coli) mazEF is an extensively studied stress-induced toxin-antitoxin (TA) system. The toxin MazF is an endoribonuclease that cleaves RNAs at ACA sites. Thereby, under stress the induced MazF generates a Stress induced Translation Machinery (STM), composed of MazF processed mRNAs and selective ribosomes that specifically translate the processed mRNAs. Here we performed a proteomic analysis of all the E. coli stress-induced proteins that are mediated through chromosomally borne mazF gene . We show that the mRNAs of almost all of them is characterized by the presence of an ACA site up to 100 nucleotides upstream to the AUG initiator. Thereby, under stressful conditions the induced MazF is processing mRNAs that are translated by STM. Furthermore, the presence of the ACA site far enough upstream (up to 100 nucleotides) to the AUG initiator may still permit translation by the canonical translation machinery. Thus, such dual translation mechanisms, enable under stress also to prepare proteins for immediate functions while coming back to normal growth conditions.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Escherichia Coli

SUBMITTER: Tamar Ziv

LAB HEAD: Hanna Engelberg-Kulka

PROVIDER: PXD010101 | Pride | 2019-02-25

REPOSITORIES: Pride

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			Action	DRS
	Seq49664_QE2.raw	Raw
	Seq49665_QE2.raw	Raw
	Seq50161_QE2.raw	Raw
	Seq50162_QE2.raw	Raw
	Seq50907_QE2.raw	Raw

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