title: Overexpression of a rice heme activator protein gene (OsHAP2E) confers resistance to pathogens, salinity and drought, and increases photosynthesis and tiller number.
abstract: Heme activator protein (HAP), also known as nuclear factor Y or CCAAT binding factor (HAP/NF-Y/CBF), has important functions in regulating plant growth, development and stress responses. The expression of rice HAP gene (OsHAP2E) was induced by probenazole (PBZ), a chemical inducer of disease resistance. To characterize the gene, the chimeric gene (OsHAP2E::GUS) engineered to carry the structural gene encoding β-glucuronidase (GUS) driven by the promoter from OsHAP2E was introduced into rice. The transgenic lines of OsHAP2Ein::GUS with the intron showed high GUS activity in the wounds and surrounding tissues. When treated by salicylic acid (SA), isonicotinic acid (INA), abscisic acid (ABA) and hydrogen peroxide (H2 O2 ), the lines showed GUS activity exclusively in vascular tissues and mesophyll cells. This activity was enhanced after inoculation with Magnaporthe oryzae or Xanthomonas oryzae pv. oryzae. The OsHAP2E expression level was also induced after inoculation of rice with M. oryzae and X. oryzae pv. oryzae and after treatment with SA, INA, ABA and H2 O2, respectively. We further produced transgenic rice overexpressing OsHAP2E. These lines conferred resistance to M. oryzae or X. oryzae pv. oryzae and to salinity and drought. Furthermore, they showed a higher photosynthetic rate and an increased number of tillers. Microarray analysis showed up-regulation of defence-related genes. These results suggest that this gene could contribute to conferring biotic and abiotic resistances and increasing photosynthesis and tiller numbers.
authors.affiliation: Faculty of Agriculture, United Graduate School of Agricultural Sciences, Ehime University, Matsuyama, Ehime, Japan.
authors.forename: Md Mahfuz
authors.initials: MM
authors.lastname: Alam
authors.forename: Toru
authors.initials: T
authors.lastname: Tanaka
authors.forename: Hidemitsu
authors.initials: H
authors.lastname: Nakamura
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ichikawa
authors.forename: Kappei
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Yaeno
authors.forename: Naoto
authors.initials: N
authors.lastname: Yamaoka
authors.forename: Kota
authors.initials: K
authors.lastname: Shimomoto
authors.forename: Kotaro
authors.initials: K
authors.lastname: Takayama
authors.forename: Hiroshige
authors.initials: H
authors.lastname: Nishina
authors.forename: Masamichi
authors.initials: M
authors.lastname: Nishiguchi
mesh_terms: D060467:Disease Resistance / Q000187:drug effects / Q000235:genetics*; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D005966:Glucuronidase / Q000378:metabolism; D020082:Magnaporthe / Q000502:physiology; D008969:Molecular Sequence Data; D012275:Oryza / Q000033:anatomy & histology* / Q000187:drug effects / Q000235:genetics* / Q000382:microbiology; D009997:Osmotic Pressure / Q000187:drug effects; D010788:Photosynthesis / Q000187:drug effects; D010935:Plant Diseases / Q000235:genetics* / Q000276:immunology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D060888:Real-Time Polymerase Chain Reaction; D054712:Salinity; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D013844:Thiazoles / Q000494:pharmacology; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D014974:Xanthomonas / Q000502:physiology
chemical_list: D010940:Plant Proteins; D013844:Thiazoles; C099063:oryzemate; D005966:Glucuronidase
keywords: CCAAT; abiotic stress; biotic stress; heme activator protein 2 (HAP2); photosynthesis; rice