title: The TOM Complex of Amoebozoans: the Cases of the Amoeba Acanthamoeba castellanii and the Slime Mold Dictyostelium discoideum.
abstract: Protein import into mitochondria requires a wide variety of proteins, forming complexes in both mitochondrial membranes. The TOM complex (translocase of the outer membrane) is responsible for decoding of targeting signals, translocation of imported proteins across or into the outer membrane, and their subsequent sorting. Thus the TOM complex is regarded as the main gate into mitochondria for imported proteins. Available data indicate that mitochondria of representative organisms from across the major phylogenetic lineages of eukaryotes differ in subunit organization of the TOM complex. The subunit organization of the TOM complex in the Amoebozoa is still elusive, so we decided to investigate its organization in the soil amoeba Acanthamoeba castellanii and the slime mold Dictyostelium discoideum. They represent two major subclades of the Amoebozoa: the Lobosa and Conosa, respectively. Our results confirm the presence of Tom70, Tom40 and Tom7 in the A. castellanii and D. discoideum TOM complex, while the presence of Tom22 and Tom20 is less supported. Interestingly, the Tom proteins display the highest similarity to Opisthokonta cognate proteins, with the exception of Tom40. Thus representatives of two major subclades of the Amoebozoa appear to be similar in organization of the TOM complex, despite differences in their lifestyle.
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Department of Bioenergetics, Poznań, Poland. Electronic address: woytek@amu.edu.pl.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Wojtkowska
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Department of Bioenergetics, Poznań, Poland; University of Muenster, Faculty of Medicine Institute of Bioinformatics, Muenster, Germany.
authors.forename: Dorota
authors.initials: D
authors.lastname: Buczek
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Department of Bioenergetics, Poznań, Poland.
authors.forename: Olgierd
authors.initials: O
authors.lastname: Stobienia
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Department of Bioenergetics, Poznań, Poland.
authors.forename: Andonis
authors.initials: A
authors.lastname: Karachitos
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Department of Bioenergetics, Poznań, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Antoniewicz
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Experimental Biology, Department of Animal Physiology and Development, Poznań, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Slocinska
authors.affiliation: University of Muenster, Faculty of Medicine Institute of Bioinformatics, Muenster, Germany.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Makałowski
authors.affiliation: Adam Mickiewicz University, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Department of Bioenergetics, Poznań, Poland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Kmita
mesh_terms: D048248:Acanthamoeba castellanii / Q000201:enzymology* / Q000235:genetics; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D004023:Dictyostelium / Q000201:enzymology* / Q000235:genetics; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D002352:Carrier Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D021122:Protein Subunits
keywords: Acanthamoeba castellanii; Amoebozoa.; Dictyostelium discoideum; TOM complex; mitochondria; phylogenesis; translocase of the outer membrane