title: Overexpression of spinach non-symbiotic hemoglobin in Arabidopsis resulted in decreased NO content and lowered nitrate and other abiotic stresses tolerance.
abstract: A class 1 non-symbiotic hemoglobin family gene, SoHb, was isolated from spinach. qRT-PCR showed that SoHb was induced by excess nitrate, polyethylene glycol, NaCl, H2O2, and salicylic acid. Besides, SoHb was strongly induced by application of nitric oxide (NO) donor, while was suppressed by NO scavenger, nitrate reductase inhibitor, and nitric oxide synthase inhibitor. Overexpression of SoHb in Arabidopsis resulted in decreased NO level and sensitivity to nitrate stress, as shown by reduced root length, fresh weight, the maximum photosystem II quantum ratio of variable to maximum fluorescence (Fv/Fm), and higher malondialdehyde contents. The activities and gene transcription of superoxide dioxidase, and catalase decreased under nitrate stress. Expression levels of RD22, RD29A, DREB2A, and P5CS1 decreased after nitrate treatment in SoHb-overexpressing plants, while increased in the WT plants. Moreover, SoHb-overexpressing plants showed decreased tolerance to NaCl and osmotic stress. In addition, the SoHb-overexpression lines showed earlier flower by regulating the expression of SOC, GI and FLC genes. Our results indicated that the decreasing NO content in Arabidopsis by overexpressing SoHb might be responsible for lowered tolerance to nitrate and other abiotic stresses.
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Xuegui
authors.initials: X
authors.lastname: Bai
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Juan
authors.initials: J
authors.lastname: Long
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Xiaozhao
authors.initials: X
authors.lastname: He
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Jinping
authors.initials: J
authors.lastname: Yan
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Xuanqin
authors.initials: X
authors.lastname: Chen
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Tan
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Kunzhi
authors.initials: K
authors.lastname: Li
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Limei
authors.initials: L
authors.lastname: Chen
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Jingming South Street, Kunming, Yunnan 650224, P.R. China.
authors.forename: Huini
authors.initials: H
authors.lastname: Xu
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D002374:Catalase / Q000235:genetics; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006454:Hemoglobins / Q000235:genetics / Q000378:metabolism*; D008315:Malondialdehyde / Q000378:metabolism; D017942:Nitric Acid / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D018724:Spinacia oleracea / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D006454:Hemoglobins; D010940:Plant Proteins; D009569:Nitric Oxide; D017942:Nitric Acid; D008315:Malondialdehyde; D002374:Catalase