Structure-function analysis of the yeast mitochondrial Rho GTPase, Gem1p: Implications for mitochondrial inheritance

Takumi Koshiba, Holly A. Holman, Kenji Kubara, Kai Yasukawa, Shun-Ichiro Kawabata, Koji Okamoto, Jane Macfarlane, Janet M. Shaw

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Mitochondria undergo continuous cycles of homotypic fusion and fission, which play an important role in controlling organelle morphology, copy number, and mitochondrial DNA maintenance. Because mitochondria cannot be generated de novo, the motility and distribution of these organelles are essential for their inheritance by daughter cells during division. Mitochondrial Rho (Miro) GTPases are outer mitochondrial membrane proteins with two GTPase domains and two EF-hand motifs, which act as receptors to regulate mitochondrial motility and inheritance. Here we report that although all of these domains are biochemically active, only the GTPase domains are required for the mitochondrial inheritance function of Gem1p (the yeast Miro ortholog). Mutations in either of the Gem1p GTPase domains completely abrogated mitochondrial inheritance, although the mutant proteins retained half the GTPase activity of the wild-type protein. Although mitochondrial inheritance was not dependent upon Ca2+ binding by the two EF-hands of Gem1p, a functional N-terminal EF-hand I motif was critical for stable expression of Gem1p in vivo. Our results suggest that basic features of Miro protein function are conserved from yeast to humans, despite differences in the cellular machinery mediating mitochondrial distribution in these organisms.

Original languageEnglish
Pages (from-to)354-362
Number of pages9
JournalJournal of Biological Chemistry
Volume286
Issue number1
DOIs
Publication statusPublished - Jan 7 2011

Fingerprint

rho GTP-Binding Proteins
Mitochondrial Genes
GTP Phosphohydrolases
EF Hand Motifs
Yeast
Yeasts
Mitochondria
Mitochondrial Proteins
Organelles
Mitochondrial Membranes
Mutant Proteins
Mitochondrial DNA
Cell Division
Machinery
Membrane Proteins
Proteins
Fusion reactions
Maintenance
Mutation

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this

Structure-function analysis of the yeast mitochondrial Rho GTPase, Gem1p : Implications for mitochondrial inheritance. / Koshiba, Takumi; Holman, Holly A.; Kubara, Kenji; Yasukawa, Kai; Kawabata, Shun-Ichiro; Okamoto, Koji; Macfarlane, Jane; Shaw, Janet M.

In: Journal of Biological Chemistry, Vol. 286, No. 1, 07.01.2011, p. 354-362.

Research output: Contribution to journalArticle

Koshiba, Takumi ; Holman, Holly A. ; Kubara, Kenji ; Yasukawa, Kai ; Kawabata, Shun-Ichiro ; Okamoto, Koji ; Macfarlane, Jane ; Shaw, Janet M. / Structure-function analysis of the yeast mitochondrial Rho GTPase, Gem1p : Implications for mitochondrial inheritance. In: Journal of Biological Chemistry. 2011 ; Vol. 286, No. 1. pp. 354-362.
@article{8007a99c32364023ba5b0c72603cd95d,
title = "Structure-function analysis of the yeast mitochondrial Rho GTPase, Gem1p: Implications for mitochondrial inheritance",
abstract = "Mitochondria undergo continuous cycles of homotypic fusion and fission, which play an important role in controlling organelle morphology, copy number, and mitochondrial DNA maintenance. Because mitochondria cannot be generated de novo, the motility and distribution of these organelles are essential for their inheritance by daughter cells during division. Mitochondrial Rho (Miro) GTPases are outer mitochondrial membrane proteins with two GTPase domains and two EF-hand motifs, which act as receptors to regulate mitochondrial motility and inheritance. Here we report that although all of these domains are biochemically active, only the GTPase domains are required for the mitochondrial inheritance function of Gem1p (the yeast Miro ortholog). Mutations in either of the Gem1p GTPase domains completely abrogated mitochondrial inheritance, although the mutant proteins retained half the GTPase activity of the wild-type protein. Although mitochondrial inheritance was not dependent upon Ca2+ binding by the two EF-hands of Gem1p, a functional N-terminal EF-hand I motif was critical for stable expression of Gem1p in vivo. Our results suggest that basic features of Miro protein function are conserved from yeast to humans, despite differences in the cellular machinery mediating mitochondrial distribution in these organisms.",
author = "Takumi Koshiba and Holman, {Holly A.} and Kenji Kubara and Kai Yasukawa and Shun-Ichiro Kawabata and Koji Okamoto and Jane Macfarlane and Shaw, {Janet M.}",
year = "2011",
month = "1",
day = "7",
doi = "10.1074/jbc.M110.180034",
language = "English",
volume = "286",
pages = "354--362",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "1",

}

TY - JOUR

T1 - Structure-function analysis of the yeast mitochondrial Rho GTPase, Gem1p

T2 - Implications for mitochondrial inheritance

AU - Koshiba, Takumi

AU - Holman, Holly A.

AU - Kubara, Kenji

AU - Yasukawa, Kai

AU - Kawabata, Shun-Ichiro

AU - Okamoto, Koji

AU - Macfarlane, Jane

AU - Shaw, Janet M.

PY - 2011/1/7

Y1 - 2011/1/7

N2 - Mitochondria undergo continuous cycles of homotypic fusion and fission, which play an important role in controlling organelle morphology, copy number, and mitochondrial DNA maintenance. Because mitochondria cannot be generated de novo, the motility and distribution of these organelles are essential for their inheritance by daughter cells during division. Mitochondrial Rho (Miro) GTPases are outer mitochondrial membrane proteins with two GTPase domains and two EF-hand motifs, which act as receptors to regulate mitochondrial motility and inheritance. Here we report that although all of these domains are biochemically active, only the GTPase domains are required for the mitochondrial inheritance function of Gem1p (the yeast Miro ortholog). Mutations in either of the Gem1p GTPase domains completely abrogated mitochondrial inheritance, although the mutant proteins retained half the GTPase activity of the wild-type protein. Although mitochondrial inheritance was not dependent upon Ca2+ binding by the two EF-hands of Gem1p, a functional N-terminal EF-hand I motif was critical for stable expression of Gem1p in vivo. Our results suggest that basic features of Miro protein function are conserved from yeast to humans, despite differences in the cellular machinery mediating mitochondrial distribution in these organisms.

AB - Mitochondria undergo continuous cycles of homotypic fusion and fission, which play an important role in controlling organelle morphology, copy number, and mitochondrial DNA maintenance. Because mitochondria cannot be generated de novo, the motility and distribution of these organelles are essential for their inheritance by daughter cells during division. Mitochondrial Rho (Miro) GTPases are outer mitochondrial membrane proteins with two GTPase domains and two EF-hand motifs, which act as receptors to regulate mitochondrial motility and inheritance. Here we report that although all of these domains are biochemically active, only the GTPase domains are required for the mitochondrial inheritance function of Gem1p (the yeast Miro ortholog). Mutations in either of the Gem1p GTPase domains completely abrogated mitochondrial inheritance, although the mutant proteins retained half the GTPase activity of the wild-type protein. Although mitochondrial inheritance was not dependent upon Ca2+ binding by the two EF-hands of Gem1p, a functional N-terminal EF-hand I motif was critical for stable expression of Gem1p in vivo. Our results suggest that basic features of Miro protein function are conserved from yeast to humans, despite differences in the cellular machinery mediating mitochondrial distribution in these organisms.

UR - http://www.scopus.com/inward/record.url?scp=78650935783&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78650935783&partnerID=8YFLogxK

U2 - 10.1074/jbc.M110.180034

DO - 10.1074/jbc.M110.180034

M3 - Article

C2 - 21036903

AN - SCOPUS:78650935783

VL - 286

SP - 354

EP - 362

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 1

ER -