title: A forward genetic approach in Arabidopsis thaliana identifies a RING-type ubiquitin ligase as a novel determinant of seed longevity.
abstract: Seed longevity is important to preserve crops and wild plants and it is limited by progressive cellular damage (aging) during storage. The induction of cellular stress defenses and the formation of the seed coat are crucial protecting events during seed development, a process mediated in Arabidopsis thaliana by the transcription factors LEC1, LEC2, FUS3 and the abscisic acid-activated ABI3. In order to identify novel determinants of seed longevity we have screened an activation-tagging mutant collection of Arabidopsis and isolated a dominant mutant with increased seed longevity under both natural and accelerated aging conditions. Molecular characterization indicates that the mutant phenotype is caused by over-expression of the At2g26130 gene encoding a RING-type zinc finger putative ubiquitin ligase. Loss of function of this gene in a T-DNA insertion mutant resulted in decreased seed longevity. We named this important gene for seed longevity RSL1 (from Ring finger of Seed Longevity1) and we could demonstrate ubiquitin ligase activity with the recombinant protein. Morphological alterations in shoot tissues of the RSL1 over-expressing plants and analysis of gibberellins levels suggest that RSL1 may increase gibberellins responses by some unknown mechanism. These results validate the forward genetic approach to seed longevity and anticipate the identification of many novel determinants of this important trait.
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Bueso
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Carla
authors.initials: C
authors.lastname: Ibañez
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Enric
authors.initials: E
authors.lastname: Sayas
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Muñoz-Bertomeu
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Gonzalez-Guzmán
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Rodriguez
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-CSIC, Camino de Vera s/n, 46022 Valencia, Spain. Electronic address: rserrano@ibmcp.upv.es.
authors.forename: Ramón
authors.initials: R
authors.lastname: Serrano
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D016922:Cellular Senescence / Q000235:genetics*; D004269:DNA, Bacterial; D015870:Gene Expression; D017343:Genes, Plant; D005875:Gibberellins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008136:Longevity; D016254:Mutagenesis, Insertional; D010641:Phenotype; D018520:Plant Shoots / Q000378:metabolism; D054829:RING Finger Domains / Q000235:genetics*; D012639:Seeds / Q000201:enzymology / Q000378:metabolism / Q000502:physiology*; D013312:Stress, Physiological / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D025801:Ubiquitin / Q000235:genetics* / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D005875:Gibberellins; C036483:T-DNA; D014157:Transcription Factors; D025801:Ubiquitin; D000040:Abscisic Acid; C000591216:RSL1 RING finger protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases
keywords: Accelerated aging; Activation tagging; Natural aging; RING ubiquitin ligases; Screening; Seed longevity