title: Tissue-specific transcriptional profiling of iron-deficient and cadmium-stressed rice using laser capture microdissection.
abstract: Several metals are essential nutrients for plants. However, they become toxic at high levels and deleteriously affect crop yield and quality. We recently reported the spatial gene expression profiles of iron (Fe)-deficient and cadmium (Cd)-stressed rice using laser microdissection and microarray analysis. The roots of Fe-deficient and Cd-stressed rice were separated into the vascular bundle (VB), cortex (Cor), and epidermis plus exodermis (EP). In addition, vascular bundles from new and old leaves at the lowest node, which are important for metal distribution, were analyzed separately (newDC and oldDC, respectively). Genes expressed in a tissue-specific manner in the VB, Cor, EP, newDC, and oldDC formed large clusters. The genes upregulated in all of the VB, Cor, and EP by Fe deficiency formed a substantial cluster that was smaller than the tissue-specific clusters. Significant numbers of genes expressed in newDC or oldDC were also expressed in VB in roots, suggesting that vascular bundles in the lowest nodes and roots have a partially common function. The expression patterns of transporter families involved in metal homeostasis were investigated, and members of each family were either expressed differentially in each tissue or showed different responses to Fe deficiency. One potassium transporter gene, OsHAK22, was upregulated by Fe deficiency in VB, Cor, and EP, suggesting that OsHAK22 is involved in potassium transport associated with mugineic acids secretion.
authors.affiliation: a Departments of Global Agricultural Sciences and Applied Biological Chemistry; Graduate School of Agricultural and Life Sciences; University of Tokyo; Bunkyo-ku, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ogo
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kakei
authors.forename: Reiko Nakanishi
authors.initials: RN
authors.lastname: Itai
authors.forename: Takanori
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Hiromi
authors.initials: H
authors.lastname: Nakanishi
authors.forename: Naoko K
authors.initials: NK
authors.lastname: Nishizawa
mesh_terms: D001692:Biological Transport; D002104:Cadmium / Q000172:deficiency / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006706:Homeostasis; D007501:Iron / Q000378:metabolism*; D000090463:Iron Deficiencies; D061346:Laser Capture Microdissection; D012275:Oryza / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018514:Plant Structures / Q000378:metabolism*; D058526:Plant Vascular Bundle / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics; D059467:Transcriptome; D015854:Up-Regulation
chemical_list: D002352:Carrier Proteins; D010940:Plant Proteins; D002104:Cadmium; D007501:Iron; D011188:Potassium
keywords: Iron; cadmium; laser microdissection; rice; transcriptome