title: Metal transport protein 8 in Camellia sinensis confers superior manganese tolerance when expressed in yeast and Arabidopsis thaliana.
abstract: Manganese (Mn) is an important micronutrient element required for plant growth and development, playing catalytic roles in enzymes, membranes and DNA replication. The tea plant (Camellia sinensis) is able to accumulate high concentration of Mn without showing signs of toxicity, but the molecular mechanisms underlying this remain largely unknown. In this study, the C. sinensis cultivar 'LJCY' had higher Mn tolerance than cultivar 'YS', because chlorophyll content reduction was lower under the high Mn treatment. Proteomic analysis of the leaves revealed that C. sinensis Metal Tolerance Protein 8 (CsMTP8) accumulated in response to Mn toxicity in cultivar 'LJCY'. The gene encoding CsMTP8, designated as CsMTP8 was also isolated, and its expression enhanced Mn tolerance in Saccharomyces cerevisiae. Similarly, the overexpression of CsMTP8 in Arabidopsis thaliana increased plant tolerance and reduced Mn accumulation in plant tissues under excess Mn conditions. Subcellular localization analysis of green florescence fused protein indicated that CsMTP8 was localized to the plasma membranes. Taken together, the results suggest that CsMTP8 is a Mn-specific transporter, which is localized in the plasma membrane, and transports excess Mn out of plant cells. The results also suggest that it is needed for Mn tolerance in shoots.
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Qinghui
authors.initials: Q
authors.lastname: Li
authors.affiliation: Botanical Gardens, Tohoku University, Aoba, Sendai 980-0862, Japan.
authors.forename: Yue
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211800, P. R. China.
authors.forename: Xiayuan
authors.initials: X
authors.lastname: Wu
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhou
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Xujun
authors.initials: X
authors.lastname: Zhu
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Wanping
authors.initials: W
authors.lastname: Fang
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D028241:Camellia sinensis / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000378:metabolism*; D008345:Manganese / Q000378:metabolism* / Q000633:toxicity; D019441:Plant Epidermis / Q000378:metabolism; D010940:Plant Proteins; D040901:Proteomics; D015003:Yeasts / Q000378:metabolism*
chemical_list: D027682:Cation Transport Proteins; D010940:Plant Proteins; D008345:Manganese