title: The membrane proteome of male gametophyte in Solanum lycopersicum.
abstract: Pollen cells possess specialized cellular compartments separated by membranes. Consequently, mature pollen contains proteinaceous factors for inter- and intracellular transport of metabolites or ions to facilitate the upcoming energy exhausting processes - germination and fertilization. Despite the current advancement in the understanding of pollen development little is known about the role and molecular nature of the membrane proteome that participates in functioning and development of male gametophyte. We dissected the membrane proteome of mature pollen from economically important crop Solanum lycopersicum (tomato). Isolated membrane fractions from mature pollen of two tomato cultivars (cv. Moneymaker and cv. Red setter) were subjected to shotgun proteomics (GEL-LC-Orbitrap-MS). The global tomato protein assignment was achieved by mapping the peptides on reference genome (cv. Heinz 1706) and de novo assembled transcriptome based on mRNA sequencing from the respective cultivar. We identified 687 proteins, where 176 were assigned as putative membrane proteins. About 58% of the identified membrane proteins participate in transport processes. In depth analysis revealed proteins corresponding to energy related pathways (Glycolysis and Krebs cycle) as prerequisite for mature pollen, thereby revealing a reliable model of energy reservoir of the male gametophyte.
  
  
  CONCLUSIONS
  Mature pollen plays an indispensable role in plant fertility and crop production. To decipher the functionality of pollen global proteomics studies have been undertaken. However, these datasets are deficient in membrane proteins due to their low abundance and solubility. The work presented here provides a comprehensive investigation of membrane proteome of male gametophyte of an agriculturally important crop plant tomato. The analysis of membrane enriched fractions from two tomato cultivars ensured an effective profiling of the pollen membrane proteome. Particularly proteins of the Krebs cycle or the glycolysis process have been detected and thus a model for the energy dynamics and preparedness of the male gametophyte for the upcoming events - germination and fertilization is provided.
authors.affiliation: Goethe University, Department of Biosciences, Molecular Cell Biology of Plants, Frankfurt/Main, Germany; SPOT-ITN Consortium.
authors.forename: Puneet
authors.initials: P
authors.lastname: Paul
authors.affiliation: SPOT-ITN Consortium; University of Vienna, Department of Ecogenomics and Systems biology, Vienna, Austria.
authors.forename: Palak
authors.initials: P
authors.lastname: Chaturvedi
authors.affiliation: Goethe University, Department of Biosciences, Molecular Cell Biology of Plants, Frankfurt/Main, Germany.
authors.forename: Mario
authors.initials: M
authors.lastname: Selymesi
authors.affiliation: University of Vienna, Department of Ecogenomics and Systems biology, Vienna, Austria; School of Biotechnology and Bioinformatics, D.Y. Patil University, Mumbai, India.
authors.forename: Arindam
authors.initials: A
authors.lastname: Ghatak
authors.affiliation: Goethe University, Department of Biosciences, Molecular Cell Biology of Plants, Frankfurt/Main, Germany; SPOT-ITN Consortium.
authors.forename: Anida
authors.initials: A
authors.lastname: Mesihovic
authors.affiliation: Goethe University, Department of Biosciences, Molecular Cell Biology of Plants, Frankfurt/Main, Germany; SPOT-ITN Consortium.
authors.forename: Klaus-Dieter
authors.initials: KD
authors.lastname: Scharf
authors.affiliation: SPOT-ITN Consortium; University of Vienna, Department of Ecogenomics and Systems biology, Vienna, Austria.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Weckwerth
authors.affiliation: Goethe University, Department of Biosciences, Molecular Cell Biology of Plants, Frankfurt/Main, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Simm
authors.affiliation: Goethe University, Department of Biosciences, Molecular Cell Biology of Plants, Frankfurt/Main, Germany; SPOT-ITN Consortium; Goethe University, Cluster of Excellence Frankfurt, Frankfurt/Main, Germany; Goethe University, Buchmann Institute of Molecular Life Sciences, Frankfurt/Main, Germany. Electronic address: schleiff@bio.uni-frankfurt.de.
authors.forename: Enrico
authors.initials: E
authors.lastname: Schleiff
mesh_terms: D020869:Gene Expression Profiling / Q000379:methods*; D018551:Solanum lycopersicum / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D011058:Pollen / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D010940:Plant Proteins; D020543:Proteome
keywords: Glycolysis; Krebs cycle; Mature pollen; Membrane associated ribosomes; Membrane proteome; Mitochondria; Plastids; RNA-seq; Tomato; Transporters