title: Characterization of MxFIT, an iron deficiency induced transcriptional factor in Malus xiaojinensis.
abstract: Iron deficiency often results in nutritional disorder in fruit trees. Transcription factors play an important role in the regulation of iron uptake. In this study, we isolated an iron deficiency response transcription factor gene, MxFIT, from an iron-efficient apple genotype of Malus xiaojinensis. MxFIT encoded a basic helix-loop-helix protein and contained a 966 bp open reading frame. MxFIT protein was targeted to the nucleus in onion epidermal cells and showed strong transcriptional activation in yeast cells. Spatiotemporal expression analysis revealed that MxFIT was up-regulated in roots under iron deficiency at both mRNA and protein levels, while almost no expression was detected in leaves irrespective of iron supply. Ectopic expression of MxFIT resulted in enhanced iron deficiency responses in Arabidopsis under iron deficiency and stronger resistance to iron deficiency. Thus, MxFIT might be involved in iron uptake and plays an important role in iron deficiency response.
authors.forename: Lili
authors.initials: L
authors.lastname: Yin
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.forename: Mudan
authors.initials: M
authors.lastname: Yuan
authors.forename: Xinzhong
authors.initials: X
authors.lastname: Zhang
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Xu
authors.forename: Zhenhai
authors.initials: Z
authors.lastname: Han
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus; D018506:Gene Expression Regulation, Plant; D007501:Iron / Q000378:metabolism; D000090463:Iron Deficiencies; D027845:Malus / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D019697:Onions / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation; D015854:Up-Regulation; D015003:Yeasts / Q000235:genetics / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D007501:Iron
keywords: Ectopic expression; Gene expression; Iron uptake; Malus xiaojinensis; Transcription factor