Journal Article

Molecular and Biochemical Characterization of the Involvement of Cyclin-Dependent Kinase A during the Early Development of Tomato Fruit

Just, Daniel, Phan, Thi-Hai, Chevalier, Christian, Joubès, Jérôme, Raymond, Philippe, Rothan, Christophe, Bergounioux, Catherine

1999

Overview

Abstract Following fruit set, the early development of tomato (Lycopersicon esculentum Mill.) fruit comprises two distinct phases: a cell division phase and a consecutive phase of cell expansion until the onset of ripening. In this study, we analyzed cytological and molecular changes characterizing these early phases of tomato fruit development. First we investigated the spatial and temporal regulation of the mitotic activity during fruit development. The DNA content of isolated nuclei from the different fruit tissues was determined by flow cytometry analysis. The results confirm the data of mitotic activity measurements and show that cell differentiation, leading to expanded cells, is characterized by endoreduplication. Second, we isolated two cDNAs, named Lyces;CDKA1 (accession no. Y17225) and Lyces;CDKA2 (accession no. Y17226), encoding tomato homologs of the cyclin-dependent kinase (CDK) p34cdc2. Tomato CDKA gene expression was followed at both the transcriptional and translational levels during fruit development. The transcripts for Lyces;CDKA1 and Lyces;CDKA2 and the corresponding CDKA proteins are predominantly accumulated during the phase of cell division between anthesis and 5 d post anthesis (DPA). In whole fruits, the maximum CDK activity was obtained between 5 and 10 DPA. The determination of the kinase activity using protein extracts from the different fruit tissues was in agreement with mitotic activity analysis. It showed the particular disappearance of the activity in the gel tissue as early as 15 DPA. The overall data of CDK activity measurements suggest a strong post-translational regulation of CDK at the temporal and spatial levels during early tomato fruit development.

• Publisher: Oxford University Press ; American Society of Plant Biologists,CCSD,American Society of Plant Physiologists,American Society of Plant Biologists
• Subject: Agronomy. Soil science and plant productions / Amino Acid Sequence / amino acid sequences / Biological and medical sciences / CDKA1 gene / CDKA2 gene / Cell cycle / Cell differentiation / chemistry / Complementary DNA / Cyclin-dependent kinase A / Economic plant physiology / enzymology / Epidermis / Flowering / Fructification and ripening / Fructification, ripening. Postharvest physiology / fruit set / Fruiting / Fruits / Fundamental and applied biological sciences. Psychology / Gels / gene expression / Gene Expression Regulation, Enzymologic / Gene Expression Regulation, Plant / Gene Library / genetics / Growth and Development / Histones / Kinetics / Life Sciences / Lycopersicon esculentum / messenger RNA / metabolism / mitosis / Molecular Sequence Data / nucleotide sequences / Pericarp / physiology / Plant cells / Plant physiology and development / Plant tissues / Protein Kinases / Protein Kinases - chemistry / Protein Kinases - genetics / Protein Kinases - metabolism / protein synthesis / Reverse Transcriptase Polymerase Chain Reaction / Sequence Alignment / Sequence Homology, Amino Acid / Solanum lycopersicum / Solanum lycopersicum - enzymology / Solanum lycopersicum - genetics / Solanum lycopersicum - physiology / Solanum lycopersicum var. lycopersicum / spatial variation / temporal variation / Tomatoes / transcription (genetics) / Transcription, Genetic / Vegetative and sexual reproduction, floral biology, fructification