Unit of Molecular Plant Physiology
Lab of Molecular Plant Physiology
tel. ++39 051 2091305
fax ++39 051 242576
Group Leader: Paolo Pupillo e Paolo Trost
E-mail : paolo.pupillo@unibo.it, paolo.trost@unibo.it
Research in progress :
- Molecular basis of the regulation of photosynthetic carbon assimilation in plants - The regulation of photosynthetic carbon metabolism involves integrated systems of control which are sensitive to environmental and physiological conditions. Rapid modulation of metabolic fluxes implies dynamic equilibria between free enzymes and supramolecular complexes with modified kinetic properties. This is the case of the GAPDH/CP12/PRK complex of the Calvin cycle. Thioredoxins and pyridin nucleotides play a role in signalling the redox state of the chloroplast and regulate photosynthetic metabolism by influencing the stability of the complex. We are studying tridimensional structures and functional properties of GAPDH/CP12/PRK isolated proteins and of the complex.
- Transmembrane redox systems: cytochromes b-561 - Plants contain several members of a family of cytochromes containing the typical transmembrane domain of cytochrome b-561 of animal chromaffine granules. Vacuolar and plasma membrane cytochrome b-561 isoforms accept electrons from cytosolic ascorbate and reduce acceptors on the other side of the membrane. In spite of potential implications in redox homeostasis in the cell wall, and in iron mobilization within the plant, this family of redox proteins is still largely unexplored. Molecular and physiological studies are in progress.
Funding :
- PRIN 2000-02 (MIUR) "Rapporti struttura-funzione nella regolazione cinetica delle gliceraldeide-3-fosfato deidrogenasi e di altre attività enzimatiche del metabolismo del carbonio."
- Regione Emilia Romagna 1997-2002 "Programma regionale sul colpo di fuoco batterico delle pomacee: Resistenza indotta in pero nei confronti di Erwinia amylovora".
- CNR 2000 "Funzioni della NAD(P)H-chinone ossidoreduttasi di Arabidopsis thaliana nell’ambito del progetto coordinato Struttura e funzione di ossidoreduttasi flaviniche".
- PRIN 2001-2003 (MIUR) "Processi ossidoreduttivi e trasduzione di energia in membrane procariotiche ed eucariotiche".
- PRIN 2003-2005 (MIUR) "Citocromi b ad alto potenziale in membrane di cellule vegetali".
- Programma Vigoni 2004-2005: Complessi supramolecolari di enzimi fotosintetici.
- FIRB 2003-2006 (MIUR) "CP12: una proteina vegetale intrinsecamente non strutturata coinvolta nella formazione di complessi supramolecolari"
- PRIN (2004-06) “Proteine CY-DOM vegetali e regolazione dello stato redox dell'ambiente apoplastico”
- PRIN (2005-07) "Bioenergetica e trasporto elettronico in sistemi batterici e vegetali"
- PRIN (2007-10) "Sistemi redox della membrana plasmatica e formazione delle radici laterali"
- Università di Bologna (2007-10) Progetto strategico STARCHitecture
- Università Italo Francese (2009-10) Progetto Galileo (con Dr. S. Lemaire, CNRS Orsay).
- PRIN (2008-11) "Meccanismi di segnalazione e regolazione redox della fotosintesi"
Patents :
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Selected Publications :
- Zaffagnini M, Michelet L, Massot V, Trost P, Lemaire SD 2008 Biochemical characterization of glutaredoxins from Chlamydomonas reinhardtii reveals the unique properties of a chloroplastic CGFS-type glutaredoxin J Biol Chem Epub 23 January 2008, 10.1074/jbc.M709567200
- Marri L, Trost P, Trivelli X, Gonnelli L, Pupillo P, Sparla F 2008 Spontaneous assembly of photosynthetic supramolecular complexes as mediated by the intrinsically unstructured protein CP12 J. Biol. Chem. 283: 1831-1838
- Zaffagnini M, Michelet L, Marchand C, Sparla F, Decottignies P, Le Maréchal P, Miginiac-Maslow M, Noctor G, Trost P, Lemaire SD 2007 The thioredoxin independent isoform of photosynthetic glyceraldehyde-3-phosphate dehydrogenase is selectively regulated by glutathionylation FEBS J. 274: 212-226
- S. Fermani, F. Sparla, G. Falini, P. L. Martelli, R. Casadio, P. Pupillo, A. Ripamonti and P. Trost 2007 Molecular mechanism of thioredoxin regulation in photosynthetic A2B2-glyceraldehyde-3- phosphate dehydrogenase Proc Natl Acad Sci USA 104: 11109-11114
- Trost P, Fermani S, Marri L, Zaffagnini M, Falini G, Scagliarini S, Pupillo P and Sparla F 2006 Thioredoxin-dependent regulation of photosynthetic glyceraldehyde-3-phosphate dehydrogenase: autonomous vs. CP12-dependent mechanisms Photosynth Research 89:1-13
- Sparla F, Costa A, Lo Schiavo F, Pupillo P, Trost P 2006 Redox regulation of a novel plastid-targeted β-amylase of Arabidopsis thaliana Plant Physiol. 141: 840-850
- Marri L, Trost P, Pupillo P, Sparla F (2005) Reconstitution and properties of the recombinant GAPDH/CP12/PRK supramolecular complex of Arabidopsis thaliana. Plant Physiology 139: 1433-1443
- Sparla F, Zaffagnini M, Wedel N, Scheibe R, Pupillo P, Trost P (2005) Regulation of photosynthetic GAPDH dissected by mutants. Plant Physiology 138: 2210-2219
- Michelet L, Zaffagnini M, Marchand CH, Collin V, Decottignies P, Tsan P, Lancelin J-M, Trost P, Miginiac-Maslow M, Noctor G, Lemaire SD (2005) Glutathionylation of chloroplast thioredoxin f: a new redox signaling mechanism in plants. Proc Natl Acad Sci USA 102: 16478-16483
- Marri L, Sparla F, Pupillo P, Trost P. (2005) Coordinated gene expression of photosynthetic glyceraldehyde-3-phosphate dehydrogenase, phosphoribulokinase and CP12 in Arabidopsis thaliana. J Exp Bot 56: 73-80
- Preger V, Scagliarini S, Pupillo P, Trost P. (2005) Identification of an ascorbate-dependent cytochrome b of the tonoplast membrane sharing biochemical features with members of the cytochrome b561 family. Planta 220: 365-375
- Sparla F, Fermani S, Falini G, Zaffagnini M, Ripamonti A, Sabatino P, Pupillo P, Trost P. (2004) Coenzyme site directed mutants of photosynthetic A4-GAPDH show selectively reduced NADPH-dependent catalysis, similar to regulatory AB-GAPDH inhibited by oxidized thioredoxin. J Mol Biol 340: 1025-37
- Potters G, Horemans N, Bellone S, Caubergs RJ, Trost P, Guisez Y, Asard H. (2004) Dehydroascorbate influences the plant cell cycle through a glutathione-independent reduction mechanism. Plant Physiol 134: 1479-1487
- Sparla F, Pupillo P, Trost P. (2002) The C-terminal extension of glyceraldehyde-3-phosphate dehydrogenase subunit B acts as an autoinhibitory domain regulated by thioredoxins and nicotinamide adenine dinucleotide. J Biol Chem 277: 44946-44952
- Fermani S, Ripamonti A, Sabatino P, Zanotti G, Scagliarini S, Sparla F, Trost P, Pupillo P. (2001) Crystal structure of the non-regulatory A4 isoform of spinach chloroplast glyceraldehyde-3-phosphate dehydrogenase complexed with NADP. J Mol Biol 314: 527-542
- Trost P, Bèrczi A, Sparla F, Sponza G, Marzadori B, Asard H, Pupillo P. (2000) Purification of cytochrome b-561 from bean hypocotyls plasma membrane. Evidence for the presence of two heme centres. Biochim Biophys Acta 1468: 1-5
Postgraduate training :
- Ph.D. Program in Cellular, Molecular and Industrial Biology (Project n. 2: Functional Biology of Cellular and Molecular Systems)
Collaborations :
Thioredoxins and glutathionylation: : Stephane D. Lemaire, Emmanuelle Issakidis-Bourguet, Myroslawa Miginiac-Maslow, Institute de Biotechnologie des Plantes, Universitè Paris-Sud, Orsay Cedex, France
Structure/function relationships of photosynthetic enzymes : Simona Fermani, Giuseppe Falini, Alberto Ripamonti, Dipartimento di Chimica G. Ciamician, Università di Bologna
Physiological role of GAPDH regulation and CP12 : Renate Scheibe, Laboratory of Plant Physiology, University of Osnabrueck
Links :
The Arabidopsis Information Resource
http://www.arabidopsis.org/home.html
Società Italiana di Fisiologia Vegetale
http://www.sifv.it/
The American society of Plant Biologists
http://www.aspb.org/
PhD Program in Functional Biology of Cellular …
http://www.dipartimentobiologia.it/doctoraltraining/pupillotrost.asp
PDB - Protein Data Bank
http://www.rcsb.org/pdb/index.html
Research group :
Mirko Zaffagnini (Post-doc)
Lucia Marri (Post-doc)
Concetta Valerio (PhD student)
Nunzio Tango (PhD student)
Valeria Preger (Post-doc)
Sandra Scagliarini (Technician)
Francesca Sparla (Research associate)
Paolo Trost (Associate professor)
Paolo Pupillo (Full professor)
