title: Genome-wide exploration of silicon (Si) transporter genes, Lsi1 and Lsi2 in plants; insights into Si-accumulation status/capacity of plants.
abstract: Silicon (Si) is a nonessential, beneficial micronutrient for plants. It increases the plant stress tolerance in relation to its accumulation capacity. In this work, root Si transporter genes were characterized in 17 different plants and inferred for their Si-accumulation status. A total of 62 Si transporter genes (31 Lsi1 and 31 Lsi2) were identified in studied plants. Lsi1s were 261-324 residues protein with a MIP family domain whereas Lsi2s were 472-547 residues with a citrate transporter family domain. Lsi1s possessed characteristic sequence features that can be employed as benchmark in prediction of Si-accumulation status/capacity of the plants. Silicic acid selectivity in Lsi1s was associated with two highly conserved NPA (Asn-Pro-Ala) motifs and a Gly-Ser-Gly-Arg (GSGR) ar/R filter. Two NPA regions were present in all Lsi1 members but some Ala substituted with Ser or Val. GSGR filter was only available in the proposed high and moderate Si accumulators. In phylogeny, Lsi1s formed three clusters as low, moderate and high Si accumulators based on tree topology and availability of GSGR filter. Low-accumulators contained filters WIGR, AIGR, FAAR, WVAR and AVAR, high-accumulators only with GSGR filter, and moderate-accumulators mostly with GSGR but some with A/CSGR filters. A positive correlation was also available between sequence homology and Si-accumulation status of the tested plants. Thus, availability of GSGR selectivity filter and sequence homology degree could be used as signatures in prediction of Si-accumulation status in experimentally uncharacterized plants. Moreover, interaction partner and expression profile analyses implicated the involvement of Si transporters in plant stress tolerance.
authors.affiliation: Department of Biology, Faculty of Science and Arts, Marmara University, Istanbul, Turkey.
authors.forename: Recep
authors.initials: R
authors.lastname: Vatansever
authors.affiliation: Department of Biology, Faculty of Science and Arts, Marmara University, Istanbul, Turkey.
authors.forename: Ibrahim Ilker
authors.initials: II
authors.lastname: Ozyigit
authors.affiliation: Department of Crop and Animal Production, Cilimli Vocational School, Duzce University, Duzce, Turkey. ertugrulfiliz@gmail.com.
authors.forename: Ertugrul
authors.initials: E
authors.lastname: Filiz
authors.affiliation: Department of Molecular Biology and Genetics, Faculty of Science, Istanbul University, Istanbul, Turkey.
authors.forename: Nermin
authors.initials: N
authors.lastname: Gozukirmizi
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000595:Amino Acid Sequence; D001692:Biological Transport; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018745:Genome, Plant; D008958:Models, Molecular; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D010944:Plants / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D000072756:Protein Conformation, alpha-Helical; D000072757:Protein Conformation, beta-Strand; D000072417:Protein Domains; D054730:Protein Interaction Domains and Motifs; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012825:Silicon / Q000378:metabolism*; D013045:Species Specificity; D013312:Stress, Physiological
chemical_list: D002352:Carrier Proteins; D010940:Plant Proteins; C020723:citrate-binding transport protein; D012825:Silicon
keywords: Accumulator; Motifs; Perturbation; Silicic acid; ar/R Selectivity filter