A role for Jsn1p in recruiting the Arp2/3 complex to mitochondria in budding yeast

Mol Biol Cell. 2005 Nov;16(11):5094-102. doi: 10.1091/mbc.e05-06-0590. Epub 2005 Aug 17.


Although the Arp2/3 complex localizes to the leading edge of motile cells, endocytic structures, and mitochondria in budding yeast, the mechanism for targeting the Arp2/3 complex to different regions in the cell is not well understood. We find that Jsn1p, a member of the PUF family of proteins, facilitates association of Arp2/3 complex to yeast mitochondria. Jsn1p localizes to punctate structures that align along mitochondria, cofractionates with a mitochondrial marker protein during subcellular fractionation, and is both protease sensitive and carbonate extractable in isolated mitochondria. Thus, Jsn1p is a peripheral membrane protein that is associated with the outer leaflet of the mitochondrial outer membrane. Jsn1p colocalized and coimmunoprecipitated with mitochondria-associated Arc18p-GFP, and purified Arp2/3 complex bound to isolated TAP-tagged Jsn1p. Moreover, deletion of JSN1 reduces the amount of Arc18p-GFP that colocalizes and is recovered with mitochondria twofold, and jsn1Delta cells exhibited defects in mitochondrial morphology and motility similar to those observed in Arp2/3 complex mutants. Thus, Jsn1p has physical interactions with mitochondria-associated Arp2/3 complex and contributes to physical and functional association of the Arp2/3 complex with mitochondria.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Actin-Related Protein 2-3 Complex*
  • Actins / metabolism
  • Fungal Proteins / metabolism*
  • Fungal Proteins / physiology*
  • Gene Deletion
  • Mitochondria / genetics
  • Mitochondria / metabolism*
  • Mitochondria / physiology
  • RNA-Binding Proteins
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / physiology*
  • Saccharomycetales


  • Actin-Related Protein 2-3 Complex
  • Actins
  • Fungal Proteins
  • JSN1 protein, S cerevisiae
  • RNA-Binding Proteins
  • Saccharomyces cerevisiae Proteins