The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)



Gene Review

POR1  -  Por1p

Saccharomyces cerevisiae S288c

Synonyms: Mitochondrial outer membrane protein porin 1, N2441, OMP2, VDAC-1, VDAC1, ...
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of POR1


High impact information on POR1

  • In contrast, a respiratory-competent strain that lacked the outer mitochondrial membrane Por1 protein showed increased sensitivity to Bax expression [3].
  • BAX-induced growth arrest was independent of the tested mitochondrial components, including voltage-dependent anion channel (VDAC), the catalytic beta subunit or the delta subunit of the F(0)F(1)-ATP synthase, mitochondrial cyclophilin, cytochrome c, and proteins encoded by the mitochondrial genome as revealed by [rho(0)] cells [4].
  • However, cells missing the POR1 gene (delta por1) were able to grow on yeast media containing a nonfermentable carbon source (glycerol) but not on such media at elevated temperature (37 degrees C) [5].
  • Multicopy suppressors of phenotypes resulting from the absence of yeast VDAC encode a VDAC-like protein [5].
  • These results rule out the contention that VDAC is indispensable for establishing the benzodiazepine binding site and are in agreement with the hypothesis that the Mr 18,000 subunit carries both the isoquinoline carboxamide and benzodiazepine binding domains [6].

Biological context of POR1

  • Two of them, namely the TOM complex channel (translocase of the outer membrane) and the PSC (peptide-sensitive channel) participate in protein translocation and are probably identical, whereas a channel-forming protein called VDAC (voltage-dependent anion channel) serves as the major pathway for metabolites [7].
  • Processes underlying the upregulation of Tom proteins in S. cerevisiae mitochondria depleted of the VDAC channel [8].
  • To clarify the role of VDAC and of the adenine nucleotide carrier, if any, in the constitution of the benzodiazepine binding site, yeast host strains were constructed in which the corresponding genes had been knocked out [6].
  • This ability of NADH to facilitate VDAC closure could be one mechanism by which glycolysis can suppress oxidative phosphorylation (Crabtree effect) [9].
  • Large scale rearrangement of protein domains is associated with voltage gating of the VDAC channel [10].

Anatomical context of POR1

  • The permeability of the outer mitochondrial membrane to most metabolites is believed to be based in an outer membrane, channel-forming protein known as VDAC (voltage-dependent anion channel) [5].
  • The presented data indicate that in S. cerevisiae-uncoupled mitochondria, external NADH, applied at higher concentrations (above 50 nmoles per 0.1 mg of mitochondrial protein), may use the TOM complex channel, besides VDAC1, to cross the outer membrane [7].
  • The VDAC channel of the mitochondrial outer membrane is voltage-gated like the larger, more complex voltage-gated channels of the plasma membrane [10].
  • Labeling of amoeba, yeast and rat liver mitochondria with [(3)H]Ro5-4864 revealed proteins identified as the voltage dependent anion selective channel (VDAC) in the outer membrane and adenine nucleotide translocase (ANT) in the inner membrane [11].
  • When VDAC is reconstituted into phospholipid (soybean) membranes, the two gating processes have virtually the same steepness of voltage dependence and the same midpoint voltage [12].

Associations of POR1 with chemical compounds

  • This protein has been found to copurify with two other mitochondrial proteins, namely the outer membrane voltage-dependent anion channel (VDAC), also known as mitochondrial porin, and the inner membrane adenine nucleotide carrier [6].
  • Its effects, different from the reported functional interactions of the channel with hexo- or creatine kinases, could not be mimicked by the protein termed VDAC modulator, indicating the presence of a novel VDAC modulator [13].
  • We find that one substitution mutation (lys 61 to glu) alters the selectivity of VDAC [14].
  • Previous in vitro studies indicated that mutation of both K234 and K236 to arginine, glutamine, or glutamic acid impaired the ability of the voltage-dependent anion channel (VDAC1) to insert into the outer membrane of the mitochondria (Smith et al. 1995) [15].
  • In addition, we have shown that the purified protein, when reconstituted into liposomes, can bind hexokinase in a glucose-6-phosphate dependent manner, as has been shown for VDAC purified from other sources [16].

Physical interactions of POR1


Regulatory relationships of POR1

  • Consequently, it may be concluded that depletion of the VDAC channel might influence differentially the expression of TOM40 and TOM70 genes [8].

Other interactions of POR1


Analytical, diagnostic and therapeutic context of POR1


  1. Bacterial expression and characterization of the mitochondrial outer membrane channel. Effects of n-terminal modifications. Koppel, D.A., Kinnally, K.W., Masters, P., Forte, M., Blachly-Dyson, E., Mannella, C.A. J. Biol. Chem. (1998) [Pubmed]
  2. Requirements of Cyc2p and the porin, Por1p, for ionic stability and mitochondrial integrity in Saccharomyces cerevisiae. Sánchez, N.S., Pearce, D.A., Cardillo, T.S., Uribe, S., Sherman, F. Arch. Biochem. Biophys. (2001) [Pubmed]
  3. Role of oxidative phosphorylation in Bax toxicity. Harris, M.H., Vander Heiden, M.G., Kron, S.J., Thompson, C.B. Mol. Cell. Biol. (2000) [Pubmed]
  4. Biochemical and genetic analysis of the mitochondrial response of yeast to BAX and BCL-X(L). Gross, A., Pilcher, K., Blachly-Dyson, E., Basso, E., Jockel, J., Bassik, M.C., Korsmeyer, S.J., Forte, M. Mol. Cell. Biol. (2000) [Pubmed]
  5. Multicopy suppressors of phenotypes resulting from the absence of yeast VDAC encode a VDAC-like protein. Blachly-Dyson, E., Song, J., Wolfgang, W.J., Colombini, M., Forte, M. Mol. Cell. Biol. (1997) [Pubmed]
  6. The Mr 18,000 subunit of the peripheral-type benzodiazepine receptor exhibits both benzodiazepine and isoquinoline carboxamide binding sites in the absence of the voltage-dependent anion channel or of the adenine nucleotide carrier. Joseph-Liauzun, E., Farges, R., Delmas, P., Ferrara, P., Loison, G. J. Biol. Chem. (1997) [Pubmed]
  7. Under conditions of insufficient permeability of VDAC1, external NADH may use the TOM complex channel to cross the outer membrane of Saccharomyces cerevisiae mitochondria. Antos, N., Stobienia, O., Budzińska, M., Kmita, H. J. Bioenerg. Biomembr. (2001) [Pubmed]
  8. Processes underlying the upregulation of Tom proteins in S. cerevisiae mitochondria depleted of the VDAC channel. Kmita, H., Antos, N., Wojtkowska, M., Hryniewiecka, L. J. Bioenerg. Biomembr. (2004) [Pubmed]
  9. NADH regulates the gating of VDAC, the mitochondrial outer membrane channel. Zizi, M., Forte, M., Blachly-Dyson, E., Colombini, M. J. Biol. Chem. (1994) [Pubmed]
  10. Large scale rearrangement of protein domains is associated with voltage gating of the VDAC channel. Peng, S., Blachly-Dyson, E., Forte, M., Colombini, M. Biophys. J. (1992) [Pubmed]
  11. Benzodiazepine binding to mitochondrial membranes of the amoeba Acanthamoeba castellanii and the yeast Saccharomyces cerevisiae. Slocinska, M., Szewczyk, A., Hryniewiecka, L., Kmita, H. Acta Biochim. Pol. (2004) [Pubmed]
  12. Oriented channel insertion reveals the motion of a transmembrane beta strand during voltage gating of VDAC. Zizi, M., Thomas, L., Blachly-Dyson, E., Forte, M., Colombini, M. J. Membr. Biol. (1995) [Pubmed]
  13. Functional differences among wheat voltage-dependent anion channel (VDAC) isoforms expressed in yeast. Indication for the presence of a novel VDAC-modulating protein? Elkeles, A., Breiman, A., Zizi, M. J. Biol. Chem. (1997) [Pubmed]
  14. Probing the structure of the mitochondrial channel, VDAC, by site-directed mutagenesis: a progress report. Blachly-Dyson, E., Peng, S.Z., Colombini, M., Forte, M. J. Bioenerg. Biomembr. (1989) [Pubmed]
  15. Mutation of K234 and K236 in the voltage-dependent anion channel 1 impairs its insertion into the mitochondrial outer membrane. Angeles, R., Devine, J., Barton, K., Smith, M., McCauley, R. J. Bioenerg. Biomembr. (1999) [Pubmed]
  16. Purification and characterization of the voltage-dependent anion channel from the outer mitochondrial membrane of yeast. Forte, M., Adelsberger-Mangan, D., Colombini, M. J. Membr. Biol. (1987) [Pubmed]
  17. A small molecule suppressor of FK506 that targets the mitochondria and modulates ionic balance in Saccharomyces cerevisiae. Butcher, R.A., Schreiber, S.L. Chem. Biol. (2003) [Pubmed]
  18. The role of yeast VDAC genes on the permeability of the mitochondrial outer membrane. Lee, A.C., Xu, X., Blachly-Dyson, E., Forte, M., Colombini, M. J. Membr. Biol. (1998) [Pubmed]
  19. Selectivity changes in site-directed mutants of the VDAC ion channel: structural implications. Blachly-Dyson, E., Peng, S., Colombini, M., Forte, M. Science (1990) [Pubmed]
  20. Molecular genetics of the VDAC ion channel: structural model and sequence analysis. Forte, M., Guy, H.R., Mannella, C.A. J. Bioenerg. Biomembr. (1987) [Pubmed]
  21. Direct measurement of VDAC-actin interaction by surface plasmon resonance. Roman, I., Figys, J., Steurs, G., Zizi, M. Biochim. Biophys. Acta (2006) [Pubmed]
WikiGenes - Universities