title: Control of e2f1 and PCNA by Drosophila transcription factor DREF.
abstract: DREF (DNA replication-related element-binding factor), a zinc finger type transcription factor required for proper cell cycle progression in both mitotic and endocycling cells, is a positive regulator of E2F1, an important transcription factor which regulates genes related to the S-phase of the cell cycle. DREF and E2F1 regulate similar sets of replication-related genes, including proliferating cell nuclear antigen (PCNA), and play roles in the G1 to S phase transition. However, the relationships between dref and e2f1 or PCNA during development are poorly understood. Here, we provided evidence for novel control of e2f1 and PCNA involving DREF in endocycling cells. Somatic clone analysis demonstrated that dref knockdown stabilized E2F1 expression at posttranscriptional levels in endocycling salivary gland cells. Similarly, PCNA expression was up-regulated in the endocycling salivary gland cells. Genetic interaction analysis indicated that the endoreplication defects are partly caused via possible enhancement of E2F1 activity. From these results and previous reports, we conclude that regulation of e2f1 and PCNA by DREF in vivo is complex and the regulation mechanism may differ with the tissue and/or positions in the tissue.
authors.affiliation: Department of Applied Biology and Insect Biomedical Research Center, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Kawamori
authors.forename: Kouhei
authors.initials: K
authors.lastname: Shimaji
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Yamaguchi
mesh_terms: D000818:Animals; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology; D004330:Drosophila / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D050687:E2F1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D007814:Larva / Q000378:metabolism; D009928:Organ Specificity; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism*; D012469:Salivary Glands / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: C099494:Dref protein, Drosophila; D029721:Drosophila Proteins; D050687:E2F1 Transcription Factor; D018809:Proliferating Cell Nuclear Antigen; D014157:Transcription Factors
keywords: DREF; Drosophila; E2F1; PCNA; endoreplication