title: Transcriptional analysis of the Arabidopsis ovule by massively parallel signature sequencing.
abstract: The life cycle of flowering plants alternates between a predominant sporophytic (diploid) and an ephemeral gametophytic (haploid) generation that only occurs in reproductive organs. In Arabidopsis thaliana, the female gametophyte is deeply embedded within the ovule, complicating the study of the genetic and molecular interactions involved in the sporophytic to gametophytic transition. Massively parallel signature sequencing (MPSS) was used to conduct a quantitative large-scale transcriptional analysis of the fully differentiated Arabidopsis ovule prior to fertilization. The expression of 9775 genes was quantified in wild-type ovules, additionally detecting >2200 new transcripts mapping to antisense or intergenic regions. A quantitative comparison of global expression in wild-type and sporocyteless (spl) individuals resulted in 1301 genes showing 25-fold reduced or null activity in ovules lacking a female gametophyte, including those encoding 92 signalling proteins, 75 transcription factors, and 72 RNA-binding proteins not reported in previous studies based on microarray profiling. A combination of independent genetic and molecular strategies confirmed the differential expression of 28 of them, showing that they are either preferentially active in the female gametophyte, or dependent on the presence of a female gametophyte to be expressed in sporophytic cells of the ovule. Among 18 genes encoding pentatricopeptide-repeat proteins (PPRs) that show transcriptional activity in wild-type but not spl ovules, CIHUATEOTL (At4g38150) is specifically expressed in the female gametophyte and necessary for female gametogenesis. These results expand the nature of the transcriptional universe present in the ovule of Arabidopsis, and offer a large-scale quantitative reference of global expression for future genomic and developmental studies.
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad y Departamento de Ingeniería Genética de Plantas, Cinvestav Irapuato CP36821 México.
authors.forename: Nidia
authors.initials: N
authors.lastname: Sánchez-León
authors.forename: Mario
authors.initials: M
authors.lastname: Arteaga-Vázquez
authors.forename: César
authors.initials: C
authors.lastname: Alvarez-Mejía
authors.forename: Javier
authors.initials: J
authors.lastname: Mendiola-Soto
authors.forename: Noé
authors.initials: N
authors.lastname: Durán-Figueroa
authors.forename: Daniel
authors.initials: D
authors.lastname: Rodríguez-Leal
authors.forename: Isaac
authors.initials: I
authors.lastname: Rodríguez-Arévalo
authors.forename: Vicenta
authors.initials: V
authors.lastname: García-Campayo
authors.forename: Marcelina
authors.initials: M
authors.lastname: García-Aguilar
authors.forename: Vianey
authors.initials: V
authors.lastname: Olmedo-Monfil
authors.forename: Mario
authors.initials: M
authors.lastname: Arteaga-Sánchez
authors.forename: Octavio Martínez
authors.initials: OM
authors.lastname: de la Vega
authors.forename: Kan
authors.initials: K
authors.lastname: Nobuta
authors.forename: Kalyan
authors.initials: K
authors.lastname: Vemaraju
authors.forename: Blake C
authors.initials: BC
authors.lastname: Meyers
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Vielle-Calzada
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D059014:High-Throughput Nucleotide Sequencing; D056771:Ovule / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins