Insights into Mtg3-mitochondrial ribosome association in Saccharomyces cerevisiae

Ribosome biogenesis is a highly regulated multistep process aided by energy-consuming auxiliary factors. GTPases form the largest class of auxiliary factors used by bacterial, cytosolic, and mitochondrial ribosomes for their maturation. Mtg3, a circularly permuted YqeH family of GTPase, is implicate...

Full description

Saved in:

Bibliographic Details
Published in:	Biochemical and biophysical research communications Vol. 737; p. 150502
Main Authors:	Kapila, Ritika, Mehra, Upasana, Kaur, Jaswinder, Verma, Yash, Jakar, Shweta, Datta, Kaustuv
Format:	Journal Article
Language:	English
Published:	United States Elsevier Inc 10-12-2024
Subjects:	cpGTPase Mitochondria Mtg3 Ribosome biogenesis YqeH YqeH Mitochondria Ribosome biogenesis cpGTPase Mtg3
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Ribosome biogenesis is a highly regulated multistep process aided by energy-consuming auxiliary factors. GTPases form the largest class of auxiliary factors used by bacterial, cytosolic, and mitochondrial ribosomes for their maturation. Mtg3, a circularly permuted YqeH family of GTPase, is implicated in the mitoribosome small subunit biogenesis. However, its precise mechanistic role has yet to be characterized. Mtg3 is likely to bind precursor mitoribosome molecules during subunit maturation in vivo. However, this interaction has yet to be observed with mitoribosomes biochemically. In this study, we delineate the specific conditions necessary for preserving the association of Mtg3 with mitoribosomes on a sucrose density gradient. We show that the C-terminal domain of Mtg3 is required for robust binding to the mitoribosome. Furthermore, point mutants likely to abrogate GTP/GDP binding and GTPase activity compromise protein function in vivo. Surprisingly, the association with the mitoribosome was not compromised in mutants likely to be deficient for nucleotide binding/hydrolysis. Thus, our finding supports a model wherein Mtg3 binds to a precursor mitoribosome through its C-terminus to facilitate a conformational change or validate a folding intermediate driven by the GTP/GDP binding and hydrolysis cycle. •Sub-CMC non-ionic detergent is required for Mtg3-mitoribosome stable interaction.•Mtg3-mitoribosome interaction does not require an active GTP-GDP cycle.•The C-terminus of Mtg3 is required for stable mitoribosome association.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0006-291X 1090-2104 1090-2104
DOI:	10.1016/j.bbrc.2024.150502