title: Identification and functional characterization of silicon transporters in soybean using comparative genomics of major intrinsic proteins in Arabidopsis and rice.
abstract: Silicon (Si) confers several benefits to many plant species when absorbed as silicic acid through nodulin 26-like intrinsic proteins (NIPs). The NIPs belong to major intrinsic protein (MIP) family, members of which form channels with high selectivity to control transport of water and different solutes. Here, comparative genomic analysis of the MIPs was performed to investigate the presence of Si transporter MIPs in soybean. Thorough analysis of phylogeny, gene organization, transcriptome profiling and protein modeling was performed to characterize MIPs in rice, Arabidopsis and soybean. Based on several attributes, two putative Si transporter genes, GmNIP2-1 and GmNIP2-2, were identified, characterized and cloned from soybean. Expression of both genes was detected in shoot and root tissues, and decreased as Si increased. The protein encoded by GmNIP2-2 showed functionality for Si transport when expressed in Xenopus oocytes, thus confirming the genetic capability of soybean to absorb the element. Comparative analysis of MIPs in plants provides opportunities to decipher gene evolution, functionality and selectivity of nutrient uptake mechanisms. Exploitation of this strategy has helped to uncover unique features of MIPs in soybean. The identification and functional characterization of Si transporters can be exploited to optimize the benefits that plants can derive from Si absorption.
authors.affiliation: Département de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation, Centre de Recherche en Horticulture, Université Laval, Quebec, Canada.
authors.forename: Rupesh K
authors.initials: RK
authors.lastname: Deshmukh
authors.forename: Julien
authors.initials: J
authors.lastname: Vivancos
authors.forename: Valérie
authors.initials: V
authors.lastname: Guérin
authors.forename: Humira
authors.initials: H
authors.lastname: Sonah
authors.forename: Caroline
authors.initials: C
authors.lastname: Labbé
authors.forename: François
authors.initials: F
authors.lastname: Belzile
authors.forename: Richard R
authors.initials: RR
authors.lastname: Bélanger
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D020346:Aquaporins / Q000235:genetics* / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D017124:Conserved Sequence; D020869:Gene Expression Profiling; D018745:Genome, Plant / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D012825:Silicon / Q000032:analysis / Q000378:metabolism*; D013025:Glycine max / Q000235:genetics* / Q000378:metabolism; D059467:Transcriptome; D014981:Xenopus
chemical_list: D020346:Aquaporins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D010940:Plant Proteins; C110065:major intrinsic protein, plant; C045625:nodulin; D012825:Silicon