title: Sequence diversity and gene expression analyses of expansin-related proteins in the white-rot basidiomycete, Phanerochaete carnosa.
abstract: Expansin and expansin-related proteins loosen plant cell wall architectures and are widely distributed in several types of organisms, including plants, fungi and bacteria. Here we describe sequence diversity and unique gene expression profiles of multiple expansin-related proteins identified in the basidiomycete, Phanerochaete carnosa. The protein sequences were homologous to loosenin, an expansin-related protein reported in the basidiomycete, Bjerkandera adusta. We identified homologous sequences of each of those P. carnosa proteins in many basidiomycete species. Twelve P. carnosa loosenin-like proteins (LOOLs) were classified into two subgroups according to sequence homology. Conservation of polysaccharide-binding amino acid residues was stricter in subgroup A. Subgroup A sequences included a conserved 8-9 amino acid insertion in a polysaccharide-binding groove whereas subgroup B contained a 12-18 amino acid insertion next to the binding groove. The P. carnosa genome also encodes the expansin-related protein, DREX1, which adopts a loosenin-like structure but has lower sequence homology to other LOOLs. The gene expression analysis of those proteins showed distinct patterns that were not significantly related to subgroupings. The variation in the protein sequences and gene expression patterns, and wide distribution among the basidiomycota, suggest that the diverse cell wall loosening proteins contribute to effective plant cell wall association and utilization by basidiomycetes.
authors.affiliation: Biomass Engineering Program, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Department of Chemical Engineering & Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada. Electronic address: hitoshi.suzuki.gc@riken.jp.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Chemical Engineering & Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada. Electronic address: thu.vuong@utoronto.ca.
authors.forename: Thu V
authors.initials: TV
authors.lastname: Vuong
authors.affiliation: Centre for the Analysis of Genome Evolution and Function, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B3, Canada. Electronic address: yunchen.gong@utoronto.ca.
authors.forename: Yunchen
authors.initials: Y
authors.lastname: Gong
authors.affiliation: Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada. Electronic address: kin@lunenfeld.ca.
authors.forename: Kin
authors.initials: K
authors.lastname: Chan
authors.affiliation: Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario M5G 1X5, Canada. Electronic address: cyho@lunenfeld.ca.
authors.forename: Chi-Yip
authors.initials: CY
authors.lastname: Ho
authors.affiliation: Department of Chemical Engineering & Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, Canada. Electronic address: emma.master@utoronto.ca.
authors.forename: Emma R
authors.initials: ER
authors.lastname: Master
authors.affiliation: Biomass Engineering Program, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan; Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada, Kobe 657-8501, Japan. Electronic address: akondo@kobe-u.ac.jp.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kondo
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001665:Binding Sites; D016000:Cluster Analysis; D017124:Conserved Sequence; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics*; D020869:Gene Expression Profiling; D014644:Genetic Variation; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020075:Phanerochaete / Q000235:genetics*; D010802:Phylogeny; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid
chemical_list: D005656:Fungal Proteins
keywords: Cell wall loosening; Expansin; Gene expression; Loosenin; Phanerochaete carnosa; Sequence homology