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PubMed · 9610732

Antisense phosphorothioate oligonucleotides specifically down-regulate cdc25B causing S-phase delay and persistent antiproliferative effects.

P A Garner-Hamrick·C Fisher
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Abstract

Cell cycle progression in mammalian cells is regulated by a family of cyclin-dependent kinases (cdks) that are activated by a family of 3 cdc25 phosphatases: cdc25A, cdc25B and cdc25C. We examined the expression of mRNA and protein of all 3 cdc25s during the HeLa cell cycle, and found that cdc25B protein has a unique and limited pattern of expression relative to other cdc25 homologs. Antisense oligonucleotides reduced cdc25B mRNA levels and dysregulated protein expression, while inhibiting S-phase progression in synchronized HeLa cells. Scrambled control oligonucleotides had no effect. Antisense oligonucleotides transfected in early G2-phase had no effect on cell cycle progression. A direct correlation between down-regulation of cdc25B and inhibition of thymidine incorporation was found using several oligonucleotides. Our results suggest a role for cdc25B in S-phase and demonstrate that inhibition of cdc25B has persistent antiproliferative effects.

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Alternative SplicingCell CycleCell Cycle ProteinsCell DivisionDown-RegulationHeLa CellsHumansIsomerismOligonucleotides, AntisensePhosphoprotein PhosphatasesRNA, MessengerS PhaseSensitivity and SpecificityThionucleotidescdc25 PhosphatasesJournal Article

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BibTeXRIS

P A Garner-Hamrick, C Fisher. 1998-05-29. Antisense phosphorothioate oligonucleotides specifically down-regulate cdc25B causing S-phase delay and persistent antiproliferative effects.. https://doi.org/10.1002/(sici)1097-0215(19980529)76%3A5%3C720%3A%3Aaid-ijc18%3E3.0.co%3B2-7

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