Disease relevance of Dref

• With two-hybrid screening using DREF as a bait, we have obtained a clone encoding a protein homologous to human myelodysplasia/myeloid leukemia factor 1 (hMLF1) [1].

High impact information on Dref

• TRF2 associates with DREF and directs promoter-selective gene expression in Drosophila [2].
• In conditions of suppressed apoptosis, DREF activation can cause overgrowth of developing organs [3].
• These data establish DREF as a global regulator of transcriptional programs that mediate cell proliferation and organ growth during animal development [3].
• DREF is required for efficient growth and cell cycle progression in Drosophila imaginal discs [3].
• We show that DREF regulates the expression of genes that are required for the transition of imaginal disc cells through S phase [3].

Biological context of Dref

• A DNA replication-related element (DRE)-binding factor (DREF) has been revealed to be an important transcription factor for activating promoters of cell proliferation and differentiation related genes [4].
• The amino acid sequences of DREF are conserved in evolutionary separate Drosophila species, Drosophila melanogaster (Dm) and Drosophila virilis (Dv) in three regions [4].
• In the present study, evidence was obtained that there are several highly conserved regions in the 5' flanking region between the DmDREF and DvDREF genes [4].
• Half-dose reduction of the dMi-2 gene enhanced the DREF-induced rough-eye phenotype [5].
• Immunostaining of polytene chromosomes of salivary glands showed that dDREF and dMi-2 bind in mutually exclusive ways [5].

Anatomical context of Dref

• While the effects on the mutation in the DNA replication-related element (DRE) in cultured cells have been studied extensively, the consequences of elevating wild-type DREF activity in developing tissues have hitherto remained unclear [6].
• Expression of DREF induced ectopic DNA synthesis in the cells behind the morphogenetic furrow, which are normally postmitotic, and abolished photoreceptor specifications of R1, R6, and R7 [7].

Associations of Dref with chemical compounds

• Chromatin immunoprecipitation assays in the presence or absence of 20-hydroxyecdysone further showed both DREF and Cut proteins to be localized in the genomic region containing the dPCNA promoter in S2 cells, especially in the Cut case upon induction of differentiation [8].
• Deduced from the nucleotide sequences of cDNA, DREF is a polypeptide of 701 amino acid residues with a molecular weight of 80,096, which contains three characteristic regions, rich in basic amino acids, proline, and acidic amino acids, respectively [9].
• Here, we report that the DNA binding activity of DREF is regulated by a redox mechanism, and that the cysteine residues are involved in this regulation [10].
• Using DRE-conjugated latex particles, DREF was affinity-purified from the Kc cell nuclear extract [11].

Physical interactions of Dref

• We found a DNA replication-related element (DRE)-like sequence located upstream of the transcription initiation site of the D-mtTFA gene and obtained results indicating that DRE-binding factor (DREF) can bind to the DRE-like sequence of the D-mtTFA gene [12].
• Gel mobility shift assays revealed that a previously identified factor called DREF (DRE- binding factor) binds to the DRE sequence in the Drosophila catalase gene [13].

Regulatory relationships of Dref

• Here we show Zen downregulates DREF gene promoter activity through action on the region between +241 and +254 (5'-AGAATACTCAACA) [4].
• Drosophila Mi-2 negatively regulates dDREF by inhibiting its DNA-binding activity [5].
• The data suggest that transcription of the D-mtTFA gene is under control of the DRE/DREF regulatory system [12].
• A half reduction of the reaper, head involution defective and grim gene dose suppressed this DREF-induced notching wing phenotype [6].
• Our data suggest strongly that the Drosophila mtSSB gene is regulated by the DRE/DREF system [14].

Other interactions of Dref

• Using a specific antibody against the dMLF, we performed immunofluorescent staining of Drosophila Kc cells and showed a primarily cytoplasmic staining, whereas DREF localizes in the nucleus [1].
• The protein is enriched in replicating tissues, and consistent with this the region upstream of the gene contains close matches to the sites of two transcription factors - Dref and E2f - which have been implicated in controlling proliferation-associated genes [15].
• To our knowledge, this is the first evidence for a genetic interaction between DREF and BEAF-32 [6].
• Antagonistic regulation of the Drosophila PCNA gene promoter by DREF and Cut [8].
• Drosophila damage-specific DNA-binding protein 1 (D-DDB1) is controlled by the DRE/DREF system [16].

Analytical, diagnostic and therapeutic context of Dref

• Electrophoretic mobility shift assays showed that dMi-2 thereby inhibits the DNA-binding activity of dDREF [5].
• Genetic crosses of transgenic flies expressing DREF to a collection of Drosophila deficiency stocks allowed us to identify several genomic regions, deletions of which caused enhancement or suppression of the DREF-induced rough eye phenotype [7].
• We used site-directed mutagenesis and in vitro transient transfection assays to establish that expression of the catalase gene is regulated by DREF through the DRE site [13].
• On gel filtration chromatography, a single peak of DREF activity was recovered in fractions corresponding to a molecular mass of 170 kDa, and the 86-kDa polypeptide was detected only in the corresponding fractions; thus, active DREF is probably a homodimeric form of the 86-kDa polypeptide [11].
• Monoclonal antibodies against Drosophila DREF inhibited the binding activity of the factor, as shown by gel mobility shift assays, and allowed specific detection of a 100 kDa protein on immuno Western blot analysis [17].

References