title: Cell type-specific responses to salinity - the epidermal bladder cell transcriptome of Mesembryanthemum crystallinum.
abstract: Mesembryanthemum crystallinum (ice plant) exhibits extreme tolerance to salt. Epidermal bladder cells (EBCs), developing on the surface of aerial tissues and specialized in sodium sequestration and other protective functions, are critical for the plant's stress adaptation. We present the first transcriptome analysis of EBCs isolated from intact plants, to investigate cell type-specific responses during plant salt adaptation. We developed a de novo assembled, nonredundant EBC reference transcriptome. Using RNAseq, we compared the expression patterns of the EBC-specific transcriptome between control and salt-treated plants. The EBC reference transcriptome consists of 37 341 transcript-contigs, of which 7% showed significantly different expression between salt-treated and control samples. We identified significant changes in ion transport, metabolism related to energy generation and osmolyte accumulation, stress signalling, and organelle functions, as well as a number of lineage-specific genes of unknown function, in response to salt treatment. The salinity-induced EBC transcriptome includes active transcript clusters, refuting the view of EBCs as passive storage compartments in the whole-plant stress response. EBC transcriptomes, differing from those of whole plants or leaf tissue, exemplify the importance of cell type-specific resolution in understanding stress adaptive mechanisms.
authors.affiliation: Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA.
authors.forename: Dong-Ha
authors.initials: DH
authors.lastname: Oh
authors.affiliation: Southern Cross Plant Science, Southern Cross University, PO Box 157, Lismore, NSW, 2480, Australia.
authors.forename: Bronwyn J
authors.initials: BJ
authors.lastname: Barkla
authors.affiliation: Instituto de Biotecnología, UNAM, A.P. 510-3, Colonia Miraval, Cuernavaca, MOR, 62250, México.
authors.forename: Rosario
authors.initials: R
authors.lastname: Vera-Estrella
authors.affiliation: Instituto de Biotecnología, UNAM, A.P. 510-3, Colonia Miraval, Cuernavaca, MOR, 62250, México.
authors.forename: Omar
authors.initials: O
authors.lastname: Pantoja
authors.affiliation: Division of Applied Life Science, Gyeongsang National University, Jinju, 660-701, South Korea.
authors.forename: Sang-Yeol
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Departments of Plant Biology and of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Bohnert
authors.affiliation: Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA.
authors.forename: Maheshi
authors.initials: M
authors.lastname: Dassanayake
mesh_terms: D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D063990:Gene Ontology; D053263:Gene Regulatory Networks / Q000187:drug effects; D035723:Mesembryanthemum / Q000166:cytology* / Q000187:drug effects / Q000235:genetics*; D058977:Molecular Sequence Annotation; D019441:Plant Epidermis / Q000166:cytology* / Q000187:drug effects / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects; D059467:Transcriptome / Q000187:drug effects / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D012965:Sodium Chloride
keywords: Crassulacean acid metabolism (CAM); Mesembryanthemum crystallinum; RNAseq; cell type-specific; epidermal bladder cell (EBC); salt stress; transcriptome; vacuole