title: Identification and characterization of a novel copper transporter gene family TaCT1 in common wheat.
abstract: Copper is an essential micronutrient for plant growth and development, and copper transporter plays a pivotal role for keeping copper homeostasis. However, little is known about copper transporters in wheat. Here, we report a novel copper transporter gene family, TaCT1, in common wheat. Three TaCT1 homoeologous genes were isolated and assigned to group 5 chromosomes. Each of the TaCT1 genes (TaCT1-5A, -5B or -5D) possesses 12 transmembrane domains. TaCT1 genes exhibited higher transcript levels in leaf than in root, culm and spikelet. Excess copper down-regulated the transcript levels of TaCT1 and copper deficiency-induced TaCT1 expression. Subcellular experiments localized the TaCT1 to the Golgi apparatus. Yeast expression experiments and virus-induced gene silencing analysis indicated that the TaCT1 functioned in copper transport. Site-directed mutagenesis demonstrated that three amino acid residues, Met(35), Met(38) and Cys(365), are required for TaCT1 function. Phylogenetic and functional analyses suggested that homologous genes shared high similarity with TaCT1 may exist exclusively in monocot plants. Our work reveals a novel wheat gene family encoding major facilitator superfamily (MFS)-type copper transporters, and provides evidence for their functional involvement in promoting copper uptake and keeping copper homeostasis in common wheat.
authors.affiliation: Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, The State Key Laboratory of Plant Cell and Chromosome Engineering, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, National Center for Plant Gene Research (Beijing), Beijing, 100101, China.
authors.forename: Haoxun
authors.initials: H
authors.lastname: Li
authors.forename: Renchun
authors.initials: R
authors.lastname: Fan
authors.forename: Libin
authors.initials: L
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Wei
authors.forename: Guoliang
authors.initials: G
authors.lastname: Li
authors.forename: Liqing
authors.initials: L
authors.lastname: Gu
authors.forename: Xianping
authors.initials: X
authors.lastname: Wang
authors.forename: Xiangqi
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001483:Base Sequence; D001692:Biological Transport / Q000187:drug effects; D032461:Chromosomes, Plant / Q000235:genetics; D003300:Copper / Q000378:metabolism* / Q000633:toxicity; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D055785:Gene Knockdown Techniques; D017343:Genes, Plant; D005816:Genetic Complementation Test; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D013347:Subcellular Fractions / Q000378:metabolism; D014908:Triticum / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D026901:Membrane Transport Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; D003300:Copper
keywords: Golgi apparatus; phylogenetic analysis; site-directed mutagenesis; virus-induced gene silencing