title: Molecular characterization of a WEE1 gene homologue in tomato (Lycopersicon esculentum Mill.).
abstract: Early fruit development in tomato (Lycopersicon esculentum Mill.) proceeds in two distinct phases of growth that comprise cell division and cell expansion, respectively. In pericarp and the jelly like locular tissue of tomato fruit, the transition between cell division to cell expansion is characterized by the arrest of mitotic activity, numerous rounds of nuclear DNA endoreduplication and the inhibition of Cyclin-Dependent Kinase A (CDKA) activity. To investigate whether the WEE1 kinase may play a role during the endoreduplication process, we isolated and characterized the tomato homologue for WEE1. The LeWEE1 gene consisted of 10 exons with a predicted 510 amino acid-long protein. The accumulation of the corresponding transcripts was associated with mitotically active organs: developing fruits, seeds and roots. Interestingly, LeWEE1was expressed in the jelly like locular tissue concomitant with endoreduplication during fruit development. Using tobacco BY-2 synchronized cells, we showed that the WEE1 gene expression is cell-cycle regulated with a maximum transcript accumulation at S phase. Our data indicate the putative dual contribution of LeWEE1 in the classical cell cycle and the endocycle.
authors.affiliation: Unité Mixte de Recherche en Physiologie et Biotechnologie Végétales (Institut de Biologie Végétale Intégrative, Universités de Bordeaux 1), BP 81, 33883 Villenave d'Ornon, Cedex, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Gonzalez
authors.forename: Michel
authors.initials: M
authors.lastname: Hernould
authors.forename: Frédéric
authors.initials: F
authors.lastname: Delmas
authors.forename: Frédéric
authors.initials: F
authors.lastname: Gévaudant
authors.forename: Philippe
authors.initials: P
authors.lastname: Duffe
authors.forename: Mathilde
authors.initials: M
authors.lastname: Causse
authors.forename: Armand
authors.initials: A
authors.lastname: Mouras
authors.forename: Christian
authors.initials: C
authors.lastname: Chevalier
mesh_terms: D000595:Amino Acid Sequence; D002453:Cell Cycle / Q000502:physiology; D002478:Cells, Cultured; D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D005091:Exons; D005638:Fruit / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018628:Gene Dosage; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D017403:In Situ Hybridization; D007438:Introns; D018551:Solanum lycopersicum / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D011494:Protein Kinases / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000166:cytology
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D010940:Plant Proteins; D011494:Protein Kinases