title: Functional analysis of the group 4 late embryogenesis abundant proteins reveals their relevance in the adaptive response during water deficit in Arabidopsis.
abstract: Late-Embryogenesis Abundant (LEA) proteins accumulate to high levels during the last stages of seed development, when desiccation tolerance is acquired, and in vegetative and reproductive tissues under water deficit, leading to the hypothesis that these proteins play a role in the adaptation of plants to this stress condition. In this work, we obtained the accumulation patterns of the Arabidopsis (Arabidopsis thaliana) group 4 LEA proteins during different developmental stages and plant organs in response to water deficit. We demonstrate that overexpression of a representative member of this group of proteins confers tolerance to severe drought in Arabidopsis plants. Moreover, we show that deficiency of LEA proteins in this group leads to susceptible phenotypes upon water limitation, during germination, or in mature plants after recovery from severe dehydration. Upon recovery from this stress condition, mutant plants showed a reduced number of floral and axillary buds when compared with wild-type plants. The lack of these proteins also correlates with a reduced seed production under optimal irrigation, supporting a role in fruit and/or seed development. A bioinformatic analysis of group 4 LEA proteins from many plant genera showed that there are two subgroups, originated through ancient gene duplication and a subsequent functional specialization. This study represents, to our knowledge, the first genetic evidence showing that one of the LEA protein groups is directly involved in the adaptive response of higher plants to water deficit, and it provides data indicating that the function of these proteins is not redundant to that of the other LEA proteins.
authors.affiliation: Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico.
authors.forename: Yadira
authors.initials: Y
authors.lastname: Olvera-Carrillo
authors.forename: Francisco
authors.initials: F
authors.lastname: Campos
authors.forename: José Luis
authors.initials: JL
authors.lastname: Reyes
authors.forename: Alejandro
authors.initials: A
authors.lastname: Garciarrubio
authors.forename: Alejandra A
authors.initials: AA
authors.lastname: Covarrubias
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics*; D017360:Arabidopsis / Q000187:drug effects* / Q000196:embryology / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D055864:Droughts; D047108:Embryonic Development / Q000187:drug effects / Q000235:genetics; D020440:Gene Duplication / Q000187:drug effects; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020868:Gene Silencing / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D018525:Germination / Q000187:drug effects; D016254:Mutagenesis, Insertional / Q000187:drug effects / Q000235:genetics; D009154:Mutation / Q000235:genetics; D009997:Osmotic Pressure / Q000187:drug effects; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects; D014867:Water / Q000494:pharmacology*
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; C066246:late embryogenesis abundant protein, plant; D014867:Water