A deletion variant partially complements a porin-less strain of Neurospora crassa.
Mitochondrial porin, the voltage-dependent anion channel, plays an important role in metabolism and other cellular functions within eukaryotic cells. To further the understanding of porin structure and function, Neurospora crassa wild-type porin was replaced with a deletion variant lacking residues 238-242 (238porin). 238porin was assembled in the mitochondrial outer membrane, but the steady state levels were only about 3% of those of the wild-type protein. The strain harbouring 238porin displayed cytochrome deficiencies and expressed alternative oxidase. Nonetheless, it exhibited an almost normal linear growth rate. Analysis of mitochondrial proteomes from a wild-type strain FGSC9718, a strain lacking porin (ΔPor-1), and one expressing only 238porin, revealed that the major differences between the variant strains were in the levels of subunits of the NADH:ubiquinone oxidoreductase (complex I) of the electron transport chain, which were reduced only in the ΔPor-1 strain. These, and other proteins related to electron flow and mitochondrial biogenesis, are differentially affected by relative porin levels.
a Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Fraser G
FG
Ferens
b Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Victor
V
Spicer
c Department of Internal Medicine & Manitoba Centre for Proteomics and Systems Biology, University of Manitoba, Winnipeg, MB R3E 3P4, Canada.
Oleg V
OV
Krokhin
a Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Anna
A
Motnenko
a Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
William A T
WA
Summers
a Department of Microbiology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Deborah A
DA
Court
D003580:Cytochromes / Q000235:genetics / Q000378:metabolism; D042967:Electron Transport Complex I / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D008928:Mitochondria / Q000737:chemistry / Q000378:metabolism; D051336:Mitochondrial Membranes / Q000737:chemistry / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000235:genetics* / Q000378:metabolism; D008958:Models, Molecular; D009492:Neurospora crassa / Q000235:genetics* / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018272:Porins / Q000172:deficiency / Q000235:genetics*; D017433:Protein Structure, Secondary; D000099188:Alternative Oxidase
D003580:Cytochromes; D042967:Electron Transport Complex I; D005656:Fungal Proteins; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D018272:Porins; D000099188:Alternative Oxidase
LC-MS/MS; Neurospora; VDAC; alternative oxidase; mitochondrial porin; oxydase alternative; porine mitochondriale