title: Regulation of PCNA and cyclin D1 expression and epithelial morphogenesis by the ZO-1-regulated transcription factor ZONAB/DbpA.
abstract: The tight junction protein ZO-1 inhibits G1/S-phase transition by cytoplasmic sequestration of a complex formed by CDK4 and the transcription factor ZONAB. Canine ZONAB is the homologue of human DbpA, an E2F target gene that is overexpressed in different carcinomas. Since the ZONAB target genes that are involved in G1/S-phase transition are unknown, we employed the mammary epithelial cell line MCF-10A and cDNA arrays to screen for such genes. We identified genes encoding cell cycle and replication proteins whose expression was altered due to increased ZONAB expression. For proliferative cell nuclear antigen and cyclin D1 genes, we show that increased mRNA levels resulted in increased protein levels and we identified ZONAB-responsive elements in their promoters by using different approaches, including chromatin immunoprecipitation assays. RNA interference and overexpression of ZONAB affected the proliferation of both MCF-10A and MDCK cells as well as the differentiation of MDCK cells into polarized cysts in three-dimensional cultures. These results indicate that ZONAB regulates the transcription of genes that are important for G1/S-phase progression and links tight junctions to the transcriptional control of key cell cycle regulators and epithelial cell differentiation.
authors.affiliation: Division of Cell Biology, Institute of Ophthalmology, University College London, Bath Street, London EC1V 9EL, United Kingdom.
authors.forename: Tony
authors.initials: T
authors.lastname: Sourisseau
authors.forename: Anastasios
authors.initials: A
authors.lastname: Georgiadis
authors.forename: Anna
authors.initials: A
authors.lastname: Tsapara
authors.forename: Robin R
authors.initials: RR
authors.lastname: Ali
authors.forename: Richard
authors.initials: R
authors.lastname: Pestell
authors.forename: Karl
authors.initials: K
authors.lastname: Matter
authors.forename: Maria S
authors.initials: MS
authors.lastname: Balda
mesh_terms: D000818:Animals; D022762:CCAAT-Enhancer-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018929:Cell Culture Techniques; D002453:Cell Cycle / Q000235:genetics; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004285:Dogs; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D005260:Female; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D042361:Mammary Glands, Human / Q000166:cytology; D008565:Membrane Proteins / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010750:Phosphoproteins / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D020218:Response Elements; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation; D062826:Zonula Occludens-1 Protein
chemical_list: D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D018809:Proliferating Cell Nuclear Antigen; C569042:TJP1 protein, human; D014157:Transcription Factors; C094867:YBX3 protein, human; C409302:ZONAB protein, Canis familiaris; D062826:Zonula Occludens-1 Protein; D019938:Cyclin D1