Cyclin-dependent kinase (CDK) inhibitors regulate the CDK-cyclin complex activities in endoreduplicating cells of developing tomato fruit.
The jelly-like locular (gel) tissue of tomato fruit is made up of large thin-walled and highly vacuolized cells. The development of the gel tissue is characterized by the arrest of mitotic activities, the inhibition of cyclin-dependent kinase A (CDKA) activity, and numerous rounds of nuclear DNA endoreduplication. To decipher the molecular determinants controlling these developmental events, we investigated the putative involvement of CDK inhibitors (p27(Kip)-related proteins, or KRPs) during the endoreduplication process. Two cDNAs, LeKRP1 and LeKRP2, encoding tomato CDK inhibitors were isolated. The LeKRP1 and LeKRP2 transcript expression was shown to be enhanced in the differentiating cells of the gel undergoing endoreduplication. At the translational level, LeKRP1 was shown to accumulate in the gel tissue and to participate in the inhibition of the CDK-cyclin kinase activities occurring in endoreduplicating cells of the gel tissue. We here propose that LeKRP1 participates in the control of both the cell cycle and the endoreduplication cycle.
Bisbis
Badia
B
Unité Mixte de Recherche 619 en Physiologie et Biotechnologie Végétales, Institut de Biologie Végétale Moléculaire, Institut National de la Recherche Agronomique, Université de Bordeaux 1, BP 81, 33883 Villenave d'Ornon Cedex, France.
Delmas
Frédéric
F
Joubès
Jérôme
J
Sicard
Adrien
A
Hernould
Michel
M
Inzé
Dirk
D
Mouras
Armand
A
Chevalier
Christian
C
D000595:Amino Acid Sequence; D002453:Cell Cycle; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D047468:Immunoprecipitation; D017403:In Situ Hybridization; D018551:Solanum lycopersicum / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016012:Poisson Distribution; D014176:Protein Biosynthesis; D025941:Protein Interaction Mapping; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D012333:RNA, Messenger; D011994:Recombinant Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004247:DNA; D018844:Cyclin-Dependent Kinases