Ettel Bubis email@example.com
Efrat Burak firstname.lastname@example.org
Mohammad Diab email@example.com
Katia Dik firstname.lastname@example.org
Reut Ben-Menachem email@example.com
Bella Kalderon firstname.lastname@example.org
Yehudit Karp email@example.com
Yuval Kellner firstname.lastname@example.org
Gleb Kogan email@example.com
Irit Kisslov firstname.lastname@example.org
Michael Leshets email@example.com
Adi Naamati firstname.lastname@example.org
Ophry Pines email@example.com
Tanya Shadur firstname.lastname@example.org
Esti Singer email@example.com
Nitzan Shakarchy firstname.lastname@example.org
Adi Rayzner (Zuberman)
Lizi Shuv (Aliza London)
Our major interests are in subcellular targeting, translocation across membranes, folding and subcellular distribution of proteins in yeast as a model for eukaryotic cells. In particular we are interested in phenomena of dual targeting and localization of proteins. To this end we have developed experimental approaches which allow physical and functional detection of dual targeted proteins that are being applied as genome wide screens.
The following are a number of topics under our investigation:
Reverse translocation: Single translation products of the FUM1 and ACO1 genes (encoding TCA cycle enzymes fumarase and aconitase) are distributed between mitochondrial and cytosolic subcellular locations. The data in vitro and in vivo indicate that partial insertion of the polypeptide chains across the mitochondrial membranes, is followed by retrograde movement of the processed protein back through the translocation pore into the cytosol. Our model, suggests that distribution involves rapid folding (outside mitochondria) which provides the driving force for this retrograde movement.
Translation coupled import: Fumarase represents proteins that cannot be imported into mitochondria after the termination of translation (post-translationally). Fast acquisition of the folded state renders fumarase precursors incompetent for translocation after completion of translation. We have recently found that mitochondrially attached polysomes are enriched for the FUM1 message in comparison to free polysomes. Nevertheless, cytosolic exposure of the fumarase nascent chain depends on both translocation and translation rates, indicating that import of fumarase into mitochondria occurs while the ribosome is still attached to the nascent chain.
Eclipsed distribution: A phenomenon of highly uneven isoenzyme distribution was recently observed and termed ‘eclipsed distribution’. In these cases, the amount of one of the isoenzymes, in one of the locations, is significantly minute and its detection by standard biochemical and visualization methods is masked by the presence of the dominant isoenzyme. Since detecting eclipsed distribution is difficult we assume that this phenomenon is probably much more common than currently recorded. Hence, developing new methods for localization and functional detection of eclipsed proteins is a challenge of our cell biology research.
Other projects include: (i) Distribution of fumarase and its function in human cells, (ii), Dual targeting mechanism of NFS1 and other proteins in yeast, (iii) Secretion of proteins and organic acid production in pathogenic fungi, and (iv) Metabolic engineering of organic acid production in yeast.
Selected recent publications
Spiegel R, Pines O, Ta-Shma A, Burak E, Shaagn A, Halvardson J, Edvardson S, Mahajna M, Zenvirt S, Saada A, Shalev S, Feuk L, Elpeleg O. 2012. Infantile cerebellar-retinal degeneration associated with mitochondrial aconitase (ACO2) mutation. Am. J. Hum. Genet. Accepted.
Mühlenhoff U, Richter N, Pines O, Pierik AJ, and Lill R. 2011. Specialized function of yeast Isa1 and Isa2 in the maturation of mitochondrial [4FE-4S] proteins. J. Biol. Chem. 286: 41205-16.
Yogev O, Naamati A and Pines O. 2011. Dual localization of fumarase and the role of cytosolic fumarase in the DNA damage response. Invited review, FEBS Journal. 278(22):4230-42.
Ben-Menachem R, Tal M, Shadur T and Pines O. 2011. A third of the yeast mitochondrial proteome is dual localized: a question of evolution. Proteomics. 11: 4468-76.
Ben-Menachem R, Regev-Rudzki N, Pines O. 2011. The aconitase C-terminal domain is an independent dual targeting element. J. Mol. Biol. 409: 113-23.
Kaufmann R, Straussberg R, Mandel H, Fattal-Valevski A, Ben-Zeev B, Naamati A, Shaag A, Zenvirt S, Konen O, Mimuni-Bloch A, Dobyns WB, Pines O, Elpeleg O. 2010. Infantile cerebral and cerebellar atrophy is associated with a mutation in the MED17 subunit of the transcription preinitiation Mediator complex. Am. J. Hum. Genet. 87:667-70.
Yogev O and Pines O. 2010. Dual targeting of mitochondrial proteins: Mechanism, regulation and function. BBA – Biomembranes. 1808: 1012-20.
Yogev O, Yogev O, Shay E, Shaulian E, Goldberg M, Fox TD, and Pines O. 2010. Fumarase: a mitochondrial metabolic enzyme and a cytosolic/nuclear component of the DNA damage response. PLoS Biol. 8 (3):e1000328.
Matthews DG, Gur N, Koopman WJH, Pines O and Vardimon L. 2010. Weak mitochondrial targeting sequence determines tissue-specific subcellular localization of glutamine synthetase in liver and brain cells. J. Cell Sci. 123: 351-9.
Eliyahu E, Pnueli L, Melamed D, Scherrer T, Gerber AP, Pines O, Rapaport D and Arava Y. 2010. Tom20 mediates localization of mRNAs to mitochondria in a translation-dependent manner. Mol. Cell Biol. 30: 284-94.
Naamati A, Regev-Rudzki N, Galperin S, Lill R and Pines O. 2009. Dual targeting of Nfs1 and discovery of its novel processing enzyme, Icp55. J. Biol. Chem., 284: 30200-8.
Spiegel R, Shaag A, Edvardson S, Mandel H, Stepensky P, Shalev S, Pines O, Elpeleg O. 2009. Bilateral striatal necrosis and polyneuropathy in childhood, due to mutation in the SLC25A19 gene, is allelic to the Amish congenital microcephaly Ann. Neurol., 66: 419-424.
Regev-Rudzki N, Battat E, Goldberg I, and Pines O. 2009. Dual localization of fumarase is dependent on the integrity of the glyoxylate shunt. Mol. Microbiol. 72: 297-306. Commentry on this paper entitled: "Putting a break on protein translocation: metabolic regulation of mitochondrial protein import" by J. Herrmann was published in the same issue.
Zeharia A, Shaag A, Houtkooper RH, Hindi T, de Lonlay P, Erez G, Huber L, Saada A, de Kayzer Y, Eshel G, Vaz FM, Pines O, Elpeleg O. 2008. Mutations in LPIN1 cause recurrent acute myoglobinuria in childhood. Am J Hum Genet, 83: 489-94.
Regev-Rudzki N, Yogev O and Pines O. 2008. The Mitochondrial Targeting Sequence tilts the balance between mitochondrial and cytosolic dual-localization. J. Cell Sci. 121: 2423-2431.
Dinur M, Tal M and Pines O. 2008. Dual Targeted Mitochondrial Proteins are Characterized by Lower MTS Parameters and Total Net Charge. PLoS ONE, 3(5):e2161, pages 1-8.
Yogev O, Karniely S and Pines O. 2007. Translation coupled translocation of yeast fumarase into mitochondria in vivo. J. Biol. Chem. 282: 29222–29229.
Regev-Rudzki N and Pines O. 2007. Eclipsed distribution: A phenomenon of dual targeting of protein and its significance. Bioessays 29:772-82.
Shlevin L, Regev-Rudzki N, Karniely S and Pines O. 2007. Targeted degradation of a dual localized protein from one subcellular compartment. Traffic, 8: 169-76.
Hadas Y, Goldberg I, Pines O, and Prusky D. 2007. Involvement of gluconic acid and glucose oxidase in the pathogenicity of Penicillium expansum in apples. Phytopathology, 97: 384-390.
Goldberg I, Rokem JS and Pines O. 2006. Organic Acids: Old Metabolites, New Themes. Journal of Chemical Technology and Biotechnology. J Chem. Technol. Biotechnol. 81:1601–1611.
Karniely S, Zuberman-Rayzner A, Sass E and Pines O. 2006. alpha-complementation as a probe for dual localization of mitochondrial proteins Exp. Cell Res. 312: 3835-3846.
Karniely S, Regev-Rudzki N, Pines O. 2006. The presequence of fumarase is exposed to the cytosol during import into mitochondria. J Mol Biol. 358:396-405.
Regev-Rudzki N, Karniely S, Ben-Haim NN, Pines O. 2005 Yeast aconitase in two locations and two metabolic pathways: seeing small amounts is believing. Mol Biol Cell. 16: 4163-71.
Karniely S, Pines O. 2005. Single translation - dual destination: mechanisms of dual protein targeting in eukaryotes. EMBO Rep. 6: 420-5.