Analysis on the mitochondrial division in Cyanidioschvzon merolae

• Published in: Journal of plant research Vol. 119; p. 124
• Main Authors: Nishida, K, Yagisawa, F, Yoshida, Y, Kuroiwa, H, Kuroiwa, T
• Format: Journal Article
• Language: English
• Published: 01.12.2006
• Subjects: Cyanidioschyzon merolae
• ISSN: 0918-9440

We performed purification and characterization of mitochondrial division protein in Cyanidioschyzon merolae. In the previous studies, we showed that a dynamin related protein CmDnm1 is recruited to assemble at mitochondrial division site in the late stage of division. Arresting cell cycle with various drugs revealed that the assembly of CmDnm1 and subsequent mitochondrial final severance are stimulated by entering into G2/M phase, and that the disassembly of CmDnm1 is restrained in G2/M arrested cells. In this study we tried to obtain a biochemical fraction that enriches CmDnm1 only when cells are arrested in G2/M phase. SDS-PAGE showed that the fraction specifically enriches CmDnm1 and an approximately 100 kDa protein, when compared with control fraction from non-arrested cells. Mass spectrometry identified it to be a protein expected to contain a coiled-coil region and seven WD repeats. Immunoblot showed the protein Mda1(Mitochondrial division apparatus 1) is accumulated during cell division. Immunofluorescence showed that Mda1 localizes at mitochondrial medial site as an arch or a ring in the early stage of mitochondrial division when CmDnm1 is dispersed among cytoplasm, and that Mda1 and CmDnm1 colocalizes only in the late stage of division. These stud suggest that Mda1 is a major component for mitochondrial division apparatus throughout division.