RRC ID 30375
著者 Nishida K, Yagisawa F, Kuroiwa H, Yoshida Y, Kuroiwa T.
タイトル WD40 protein Mda1 is purified with Dnm1 and forms a dividing ring for mitochondria before Dnm1 in Cyanidioschyzon merolae.
ジャーナル Proc Natl Acad Sci U S A
Abstract Mitochondria are not produced de novo but are maintained by division. Mitochondrial division is a coordinated process of positioning and constriction of the division site and fission of double membranes, in which dynamin-related protein is believed to mediate outer membrane fission. Part of the mitochondrial division machinery was purified from M phase-arrested Cyanidioschyzon merolae cells through biochemical fractionation. The dynamin-related protein Dnm1 was one of the two major proteins in the purified fraction and was accompanied by a newly identified protein CMR185C, named Mda1. Mda1 contained a predictable coiled-coil region and WD40 repeats, similarly to Mdv1 and Caf4 in yeasts. Immunofluorescence and immunoelectron microscopy showed that Mda1 localizes as a medial belt or ring on the mitochondrial outer surface throughout the division. The ring formation of Mda1 followed the plane of the ring of FtsZ, a protein that resides in the matrix. Dnm1 consistently colocalized with Mda1 only in the late stages of division. Mda1 protein was expressed through S to M phases and was phosphorylated specifically in M phase when Mda1 transformed from belt into foci and became colocalizing with Dnm1. Dephosphorylation of Mda1 in vitro increased its sedimentation coefficient, suggesting conformational changes of the macromolecule. Disassembly of the purified mitochondrial division machinery was performed by adding GTP to independently release Dnm1, suggesting that Mda1 forms a stable homo-oligomer by itself as a core structure of the mitochondrial division machinery.
巻・号 104(11)
ページ 4736-41
公開日 2007-3-13
DOI 10.1073/pnas.0609364104
PII 0609364104
PMID 17360593
PMC PMC1838669
MeSH Arabidopsis Proteins Guanosine Triphosphate / chemistry Intracellular Signaling Peptides and Proteins / chemistry* Intracellular Signaling Peptides and Proteins / physiology* Microscopy, Fluorescence Microscopy, Immunoelectron Mitochondria / metabolism Phosphorylation Plant Proteins / chemistry Plant Proteins / physiology* Protein Binding Protein Structure, Tertiary Rhodophyta / metabolism*
IF 9.412
引用数 26
WOS 分野 CELL BIOLOGY
リソース情報
藻類 NIES-3377