title: Carbon Monoxide Interacts with Auxin and Nitric Oxide to Cope with Iron Deficiency in Arabidopsis.
abstract: To clarify the roles of carbon monoxide (CO), nitric oxide (NO), and auxin in the plant response to iron deficiency (-Fe), and to establish how the signaling molecules interact to enhance Fe acquisition, we conducted physiological, genetic, and molecular analyses that compared the responses of various Arabidopsis mutants, including hy1 (CO deficient), noa1 (NO deficient), nia1/nia2 (NO deficient), yuc1 (auxin over-accumulation), and cue1 (NO over-accumulation) to -Fe stress. We also generated a HY1 over-expression line (named HY1-OX) in which CO is over-produced compared to wild-type. We found that the suppression of CO and NO generation using various inhibitors enhanced the sensitivity of wild-type plants to Fe depletion. Similarly, the hy1, noa1, and nia1/nia2 mutants were more sensitive to Fe deficiency. By contrast, the yuc1, cue1, and HY1-OX lines were less sensitive to Fe depletion. The hy1 mutant with low CO content exhibited no induced expression of the Fe uptake-related genes FIT1 and FRO2 as compared to wild-type plants. On the other hand, the treatments of exogenous CO and NO enhanced Fe uptake. Likewise, cue1 and HY1-OX lines with increased endogenous content of NO and CO, respectively, also exhibited enhanced Fe uptake and increased expression of bHLH transcriptional factor FIT1as compared to wild-type plants. Furthermore, we found that CO affected auxin accumulation and transport in the root tip by altering the PIN1 and PIN2 proteins distribution that control lateral root structure under -Fe stress. Our results demonstrated the integration of CO, NO, and auxin signaling to cope with Fe deficiency in Arabidopsis.
authors.affiliation: Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environment Protection, Jiangsu Key Laboratory for Eco-Agriculture Biotechnology around Hongze Lake, Huaiyin Normal UniversityHuaian, China; Crop Protection and Management Research Unit, Agricultural Research Service - United States Department of AgricultureTifton, GA, USA; Department of Plant Pathology, The University of GeorgiaTifton, GA, USA.
authors.forename: Liming
authors.initials: L
authors.lastname: Yang
authors.affiliation: Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environment Protection, Jiangsu Key Laboratory for Eco-Agriculture Biotechnology around Hongze Lake, Huaiyin Normal University Huaian, China.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Ji
authors.affiliation: Crop Genetics and Breeding Research Unit, Agricultural Research Service - United States Department of Agriculture Tifton, GA, USA.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Wang
authors.affiliation: Crop Genetics and Breeding Research Unit, Agricultural Research Service - United States Department of Agriculture Tifton, GA, USA.
authors.forename: Karen R
authors.initials: KR
authors.lastname: Harris-Shultz
authors.affiliation: Department of Plant Production, College of Food and Agricultural Sciences, King Saud University Riyadh, Saudi Arabia.
authors.forename: Elsayed F
authors.initials: EF
authors.lastname: Abd Allah
authors.affiliation: Jiangsu Collaborative Innovation Center of Regional Modern Agriculture and Environment Protection, Jiangsu Key Laboratory for Eco-Agriculture Biotechnology around Hongze Lake, Huaiyin Normal University Huaian, China.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Institute of Tibet Plateau Research at Kunming, Chinese Academy of Sciences Kunming, China.
authors.forename: Yanlong
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Institute of Tibet Plateau Research at Kunming, Chinese Academy of Sciences Kunming, China.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Hu
keywords: Arabidopsis; CO; NO; auxin; basipetal transport; iron deficiency