title: Redox regulation of methionine in calmodulin affects the activity levels of senescence-related transcription factors in litchi.
abstract: Reactive oxygen species (ROS) play a role in aging and senescence in organisms. The oxidation of methionine (Met) residues in proteins to Met sulfoxide by ROS can cause conformational alteration and functional impairments. Met oxidation is reversed by Met sulfoxide reductase (Msr) A and B. Currently, the repair of oxidized proteins by Msr and Msr-mediated physiological functions are not well understood, especially in higher plants. The down-regulated expression of LcMsrA1/B1 may be involved in the senescence of litchi (Litchi chinensis) fruit. We verified that LcCaM1 is a substrate of LcMsrA1 and LcMsrB1 in vitro and in vivo, and oxidized LcCaM1 could be repaired by LcMsrA1 in combination with LcMsrB1. Moreover, LcMsrA1 and LcMsrB1 play important roles in repairing oxidized Met110 and Met125 residues, respectively, in LcCaM1. Furthermore, the Met oxidation in LcCaM1 did not affect its physical interactions with two LcCaM1-binding senescence-related transcription factors LcNAC13 and LcWRKY1, but enhanced their DNA-binding activities. Therefore, we hypothesized that the down-regulated expression of LcMsrA1/B1 results in the accelerated oxidation of LcCaM1, which enhanced the DNA-binding activities of LcNAC13 and LcWRKY1, thereby activating or repressing the expression of senescence-related genes.
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Guoxiang
authors.initials: G
authors.lastname: Jiang
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Huiling
authors.initials: H
authors.lastname: Yan
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Fuwang
authors.initials: F
authors.lastname: Wu
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Xuncheng
authors.initials: X
authors.lastname: Liu
authors.affiliation: Guangdong Food and Drug Vocational College, Guangzhou 510520, China.
authors.forename: Xinguo
authors.initials: X
authors.lastname: Su
authors.affiliation: College of Chemistry and Biology Engineering, Guilin University of Technology, Gulin 541004, China.
authors.forename: Xinhong
authors.initials: X
authors.lastname: Dong
authors.affiliation: Department of Environmental Health Science, College of Public Health, University of Georgia, Athens, GA 30602, USA.
authors.forename: Jiasheng
authors.initials: J
authors.lastname: Wang
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China. Electronic address: xwduan@scbg.ac.cn.
authors.forename: Xuewu
authors.initials: X
authors.lastname: Duan
authors.affiliation: Guangdong Provincial Key Laboratory of Applied Botany/Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Yueming
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000595:Amino Acid Sequence; D002147:Calmodulin / Q000378:metabolism*; D016922:Cellular Senescence / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000378:metabolism; D015536:Down-Regulation / Q000502:physiology; D032125:Litchi / Q000378:metabolism*; D008715:Methionine / Q000031:analogs & derivatives / Q000378:metabolism*; D051150:Methionine Sulfoxide Reductases / Q000378:metabolism; D010084:Oxidation-Reduction; D010940:Plant Proteins / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D002147:Calmodulin; D004268:DNA-Binding Proteins; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D014157:Transcription Factors; D008715:Methionine; D051150:Methionine Sulfoxide Reductases; C027219:methionine sulfoxide reductase; C013111:methionine sulfoxide
keywords: Calmodulin; Litchi; Methionine sulfoxide reductase; Reactive oxygen species; Senescence; Transcriptional regulation