title: Vitamin C deficiency improves somatic embryo development through distinct gene regulatory networks in Arabidopsis.
abstract: Changes in the endogenous ascorbate redox status through genetic manipulation of cellular ascorbate levels were shown to accelerate cell proliferation during the induction phase and improve maturation of somatic embryos in Arabidopsis. Mutants defective in ascorbate biosynthesis such as vtc2-5 contained ~70 % less cellular ascorbate compared with their wild-type (WT; Columbia-0) counterparts. Depletion of cellular ascorbate accelerated cell division processes and cellular reorganization and improved the number and quality of mature somatic embryos grown in culture by 6-fold compared with WT tissues. To gain insight into the molecular mechanisms underlying somatic embryogenesis (SE), we profiled dynamic changes in the transcriptome and analysed dominant patterns of gene activity in the WT and vtc2-5 lines across the somatic embryo culturing process. Our results provide insight into the gene regulatory networks controlling SE in Arabidopsis based on the association of transcription factors with DNA sequence motifs enriched in biological processes of large co-expressed gene sets. These data provide the first detailed account of temporal changes in the somatic embryo transcriptome starting with the zygotic embryo, through tissue dedifferentiation, and ending with the mature somatic embryo, and impart insight into possible mechanisms for the improved culture of somatic embryos in the vtc2-5 mutant line.
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, MB, R3T2N2, Canada.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Becker
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, MB, R3T2N2, Canada.
authors.forename: Ainsley
authors.initials: A
authors.lastname: Chan
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, MB, R3T2N2, Canada.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Mao
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, MB, R3T2N2, Canada.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Girard
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, MB, R3T2N2, Canada.
authors.forename: Samantha
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Botany, Faculty of Science, Tanta University, Tanta, 31527, Egypt.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Elhiti
authors.affiliation: Department of Plant Science, University of Manitoba, Winnipeg, MB, R3T2N2, Canada.
authors.forename: Claudio
authors.initials: C
authors.lastname: Stasolla
authors.affiliation: Department of Biological Sciences, University of Manitoba, Winnipeg, MB, R3T2N2, Canada Mark.Belmonte@umanitoba.ca.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Belmonte
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D001205:Ascorbic Acid / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D053263:Gene Regulatory Networks; D009154:Mutation; D010084:Oxidation-Reduction; D058439:Plant Somatic Embryogenesis Techniques / Q000379:methods*; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D059467:Transcriptome
chemical_list: D001205:Ascorbic Acid
keywords: Arabidopsis thaliana; ascorbic acid; gene regulatory networks; redox; somatic embryogenesis; transcriptome