title: L-Cysteine inhibits root elongation through auxin/PLETHORA and SCR/SHR pathway in Arabidopsis thaliana.
abstract: L-Cysteine plays a prominent role in sulfur metabolism of plants. However, its role in root development is largely unknown. Here, we report that L-cysteine reduces primary root growth in a dosage-dependent manner. Elevating cellular L-cysteine level by exposing Arabidopsis thaliana seedlings to high L-cysteine, buthionine sulphoximine, or O-acetylserine leads to altered auxin maximum in root tips, the expression of quiescent center cell marker as well as the decrease of the auxin carriers PIN1, PIN2, PIN3, and PIN7 of primary roots. We also show that high L-cysteine significantly reduces the protein level of two sets of stem cell specific transcription factors PLETHORA1/2 and SCR/SHR. However, L-cysteine does not downregulate the transcript level of PINs, PLTs, or SCR/SHR, suggesting that an uncharacterized post-transcriptional mechanism may regulate the accumulation of PIN, PLT, and SCR/SHR proteins and auxin transport in the root tips. These results suggest that endogenous L-cysteine level acts to maintain root stem cell niche by regulating basal- and auxin-induced expression of PLT1/2 and SCR/SHR. L-Cysteine may serve as a link between sulfate assimilation and auxin in regulating root growth.
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, 230027, China; Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, 230027, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.forename: Jie-Li
authors.initials: JL
authors.lastname: Mao
authors.forename: Ying-Jun
authors.initials: YJ
authors.lastname: Zhao
authors.forename: Chuan-You
authors.initials: CY
authors.lastname: Li
authors.forename: Cheng-Bin
authors.initials: CB
authors.lastname: Xiang
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D019328:Buthionine Sulfoximine / Q000494:pharmacology; D003545:Cysteine / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism*; D018519:Meristem / Q000187:drug effects / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D020675:Peroxisomes / Q000187:drug effects / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development*; D012694:Serine / Q000031:analogs & derivatives / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D055153:Stem Cell Niche / Q000187:drug effects; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; C493246:PLT1 protein, Arabidopsis; C493247:PLT2 protein, Arabidopsis; C100978:SCR protein, Arabidopsis; C410510:SHORT ROOT protein, Arabidopsis; D014157:Transcription Factors; D049452:Green Fluorescent Proteins; D012694:Serine; D019328:Buthionine Sulfoximine; C043943:O-acetylserine; D003545:Cysteine
keywords: Auxin; L-cysteine; PIN; PLETHORA; root stem cell; root system architecture