IMR Press / FBL / Volume 25 / Issue 4 / DOI: 10.2741/4825
Epigenetic regulation affects gene amplification in Drosophila development
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1 Faculty of Teacher Education, Shumei University, Daigakucho 1-1, Yachiyo, Chiba, Japan 276-0003
2 Department of Molecular Cellular and Biochemistry, The Ohio State Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
3 Department of Chemistry, Faculty of Science, Hokkaido University, Kita-ku, Sapporo, Hokkaido, Japan 060-0810
4 Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
Send correspondence to: Hidetsugu Kohzaki, Faculty of Teacher Education, Shumei University, Daigakucho 1-1, Yachiyo, Chiba, Japan 276-0003, Tel: 81-47-409-1479, Fax: 81-47-409-9357, E-mail:
Front. Biosci. (Landmark Ed) 2020, 25(4), 632–645;
Published: 1 January 2020

In Drosophila melanogaster, in response to developmental transcription factors, and by repeated initiation of DNA replication of four chorion genes, ovarian follicle cells, form an onion skin-type structure at the replication origins. The DNA replication machinery is conserved from yeast to humans. Subunits of the origin recognition complex (ORC) is comprised of Orc1, Orc2, and Cdc6 genes. While mutations of Orc1 and Orc2 and not Cdc6can be lethal, overexpression of these genes lead to female sterility. Ecdysone, is a steroidal prohormone of the major insect molting hormone 20-hydroxyecdysone that in Drosophila, triggers molting, metamorphosis, and oogenesis. To this end, we identified several ecdysone receptor (EcR) binding sites around gene amplification loci. We also found that H3K4 was trimethylated at chorion gene amplification origins, but not at the act1 locus. Female mutants overexpressing Lsd1 (a dimethyl histone H3K4 demethylase) or Lid (a trimethyl histone H3K4 demethylase), but not a Lid mutant, were sterile. The data suggest that ecdysone signaling determines which origin initiates DNA replication and contributes to the development. Screening strategies using Drosophila offer the opportunity for development of drugs that reduce gene amplification and alter histone modification associated with epigenetic effects.

gene amplification

In Drosophila melanogaster, different DNA replication systems are used during development (1- 5). During Drosophila oogenesis, endoreplication occurs in nurse cells, whereas both endoreplication and chorion gene amplification occur in follicle (fc) cells (1-5). The amplification of Drosophila chorion genes is necessary for eggshell formation, and mutations that disrupt amplification, such as those in cyclin E, orc2 (6, 7), chiffon (Dbf4) (8), humpty dumpty (9), and mcm6, cause female sterility. Orc2, orc5, and orc6 mutants have strong S-phase defects (7,10, 11). Surprisingly, dE2F1, dDP (12), dE2F2 (13, 14), Rbf (15), and the Myb complex (16,17) are necessary for this gene amplification process (18,19). We previously proposed that chorion gene amplification after repeated initiation of DNA replication at the origins occurs in response to developmental signals, initiated via transcription factors, in ovarian fc cells (20).

Orc1 is a large subunit of the origin recognition complex (ORC) and functions as the main subunit of the prereplication complex. In Drosophila, Orc1 levels are transcriptionally upregulated by E2F (21, 22) and downregulated by the anaphase promoting complex via proteolysis (23, 24). Neither Orc1 nor Orc2 in the salivary and ovarian fc cells is required for endoreplication (25). In the absence of Orc1, most amplification is diminished, whereas if Orc1 is overexpressed, DNA replication occurs throughout the nucleus. These results suggest that Orc1 is a limiting factor at least in some tissues (22). On the other hand, endoreplication in Drosophila does not require ORC for initiation, demonstrating that ORC-independent DNA replication can also occur (25).

In this study, we investigated where initiation of DNA replication begins and what triggers it at the chorion gene loci. in Drosophila. we report that regulation of signal transduction and DNA replication, especially with respect to the ecdysone receptor (EcR) and its cofactor TRR (26, 27), a histone H3 lysine 4 (H3K4) trimethylase, determines Orc1 loading at these loci.

3.1. Fly stocks

Fly strains were maintained at 25°C on standard food. C323a-Gal4 driver and flies harboring UAS-EcR isoform transgene were obtained from the Bloomington Stock Center. Flies with orc1+-promoter-Orc1-GFP-9myc, UAS-Orc2-GFP-9myc, UAS-Orc1-GFP-9myc, UAS-Cdc6-GFP-9myc, or UAS-GFP were from M. Asano (Duke University Medical Center). UAS-Lsd1 was a gift from N. Dyson (HarvardMedical School, Boston, USA). UAS-Lid and UAS-Lid jmjC* were from R.N. Eisenman (Fred Hutchinson Cancer Research Center, Seattle, USA). Female sterility experiments were performed as described previously (28).

3.2. ChIP assay

ChIP assays were performed mainly according to Kohzaki et al. (29, 30). Egg chambers from Orc1-GFP-9myc flies (23) were dissected from the ovaries of fattened flies in non-supplemented Grace’s medium (GIBCO-BRL). Formaldehyde was added to a final concentration of 2%, and cross-linking was allowed to proceed for 15 min at room temperature on a rotator. The cross-linking reaction was stopped by incubation with glycine at a final concentration of 0.125 mM for 5 min. The cross-linked egg chambers were washed twice with 1 ml of TBS, then twice with 1 ml of lysis buffer (30). The egg chambers were disrupted by sonication. Sonication and all postsonication procedures were performed as described previously (30). IgG (ab18413) and Myc antibody (9E10) was used in the ChIP assays. EcR and TRR antibodies were described previously (26, 27). H3K4me3 (ab8580) and H3K4me2 (ab7766) antibodies were purchased from Abcam (Cambridge, UK). Primers used were the same as those reported previously (29, 30).

3.3. Microscopy and histology

Total RNA was isolated using Trizol Reagent (Invitrogen). Oligo dT primers and a Takara high fidelity RNA PCT kit (Takara, Kyoto, Japan) were used for generation of complementary DNA. Then, real-time PCR was performed using a SYBR Green I kit (Takara) and the Applied Biosystems 7500 real-time PCR system (Applied Biosystems, Foster City, CA, USA). RNA expression efficiencies decreased to 25% in every case (28).

4.1. Orc1 loading coincides with gene amplification locus for Drosophila oogenesis

Steroid hormones, including the prohormone ecdysone, play crucial roles during animal development. In Drosophila, ecdysone triggers molting, metamorphosis, and oogenesis through its effect on the gene expression network (28, 31-41). Ecdysone functions by binding to a nuclear receptor, EcR (42). EcR heterodimerizes with the retinoid X receptor ortholog Ultraspiracle (USP), which acts as a general heterodimer partner for the class of factors represented by EcR (39, 43-45). This heterodimer is required for binding to the ligands or their target DNA. The dimer activates EcR response gene expression by recruiting co-regulators. TRR, which is a histone methyltransferase capable of trimethylating H3K4, is required as a coactivator of EcR by modifying the chromatin structure at ecdysone-responsive promoters (26, 27). Ecdysone induces gene amplification at the Sciara coprophila DNA puff II/9A (46, 47).

Recently, we showed that Orc1 binds to ace1, ace, and ori-β directly (30) using flies with a single copy orc1 promoter orc1+-GFP-9myc transgene (Orc1-GFP9myc) (23). In eye imaginal disc of this transgenic fly, the behavior of Orc1-GFP9myc was essentially identical to that of ORC1. 1. Accumulation of Orc1-GFP9myc prior to CycB in late G1 or early S phase, 2. Persistence of both Orc1-GFP9myc and CycB throughout G2, 3. Removal of Orc1-GFP9myc from chromatin during M phase upon accumulation of PH3, 4. Disappearance of all three antigens (Orc1-GFP9myc, CycB and PH3) upon entry into the subsequent G1 (24) but not in ovary, especially in follicle cells. We previously showed that the transgene expressed in ovary using ChIP assay (30). Here we considered this issue using microscopes histologically.

In this Orc1-GFP9myc fly, Orc1-GFP was expressed similarly to endogenous Orc1 (Figure 1A and C) and localized to fc cells (Figure 1B and D). We asked whether response elements are found around the gene amplification loci. We detected several EcR putative binding sites (Figure 2A). In these fly ovaries, we performed a ChIP assay using EcR-C monoclonal antibody and TRR polyclonal antibody (26, 27). We detected signals at ace3, ori-β, and ace1 (Figure 2B and C). The amounts of ace1, ace3, and ori-β PCR products obtained using EcR, TRR, H3K4me3, Myc (for Orc1) and IgG antibodies relative to those obtained using H3K4me2 antibody were considerably different (t-test, p < 0.05) (48). Also, the amounts of ace1, ace3, and ori-β PCR products obtained using EcR, TRR, Tri-Me, and Myc (for Orc1) antibodies were not statistically different (t-test, p > 0.05) (48) (Figure 2). These data suggest that EcR, TRR, and Orc1 might form a complex for initiation of DNA replication.

Figure 1

Distribution of Orc1 and Orc1-3HA-GFP. (A, B) Antibody straining reveals the distribution of endogenous Orc1 using anti-Orc1. (C, D) Fluorescent signals from Orc1-GFP9myc driven by the orc1 promoter. This transgene was in a wild-type background. In A and C, arrowheads show the morphogenetic furrow (MF) in eye-antennal imaginal discs. MF migrates from the posterior (the left side) to the anterior (the right side). Most eye disc cells first undergo one synchronous cell cycle and then enter a prolonged G1/G0 phase. In B and D, dots indicate gene amplification loci associated with Orc1 and Orc1-3HA-GFP.

Figure 2

(A) Schematic representation of EcR-binding sites. Asterisks indicate putative binding sites. The USP-binding site was reported previously (60-61). (B) Association of EcR, TRR, H3K4me3, H3K4me2, and Orc1-GFPmyc with chorion gene elements in vivo. ChIP assays were performed as described in Methods with anti-EcR, anti-TRR, anti-H3K4me3, anti-H3K4me2, and anti-myc antibody. DNA was amplified using PCR primers specific to ace1, ace3, ori-β, and act5C 5’UTR as described previously (29) in Figure 2A. These primers were also used to amplify DNA isolated from whole cell extracts before immunoprecipitation (WCE). The experiments were repeated to confirm reproducibility. The same PCR products were loaded onto separate gels for each primer set. The samples derived from the same experiment and the gels were processed in parallel. “– “ was shown that IgG was used as negative control. (C) Quantitation of ChIP assays was performed at the times as described (N) using NIH image (Image J). The amounts of PCR products obtained from 10% input of WCE were taken to be equal to 1.0. As negative control, IgG was used. As a sample, about ori-β PCR products, the product of EcR, TRR, Tri-Me and Orc1 was compared with that of Di -Me. *; T test, p<0.05. The amounts of ace1, ace3, and ori-β PCR products obtained using EcR, TRR, Tri-Me, and Myc (for Orc1) antibodies were not statistically different (t-test, p > 0.05).

4.2. Epigenetic controls lead to Orc1 loading at gene amplification loci

Four EcR isoforms have been isolated (41, 49), and each has a tissue-specific function during development. We overexpressed each EcR in fc cells. Overexpression of all EcRs except EcR.B1 led to female sterility, but overexpression of the EcR mutant F645A, which did not have transcription activity, did not (Figure 3A). Therefore, ecdysone may regulate gene amplification directly through transactivation.

Figure 3

(A) Overexpression of dominant negative forms of EcR led to female sterility. Females with the c323a-Gal4 driver were crossed with male flies harboring a UAS-EcR isoform transgene (a responder). The progeny (males or females) having the indicated responder and c323awere crossed with wild-type Canton-S (CS) flies. All responders were tested: if no bar is visible, there were no progeny with wild-type growth rates and rates of larvae emergence. The experiments were performed several times (N). The numbers of progeny from CS (male) × c323a expressing EcR families (female) are 100% (blue bars in Figure 3A). (B) Overexpression of Lsd1 and Lid, but not Lid jmjC*, led to female sterility. Assays were performed as described in Figure 3A with flies harboring UAS-Lsd1, UAS-Lid, or UAS-Lid jmjC* transgenes. The experiments were performed several times (N). The numbers of progeny from CS (male) × c323a expressing Lsd, Lid, or Lid jmjC* families (female) are 100% (blue bars in Figure 3A).

We next asked whether H3K4 is converted to the trimethylated form (H3K4me3) by TRR. TRR was identified as a Set domain protein in Drosophila and is highly homologous to Drosophila TRITHORAX protein and to human ALL-1/HRX. TRR mutants trr1 and trr3 are embryonic lethal 8 (26). H3K4me3 is associated with transcriptionally active genes in eukaryotes (50, 51). We checked the localization of H3K4me3 around the gene amplification loci. Actin 5C is transcribed during early embryogenesis, and its 5’UTR is trimethylated, not dimethylated. We found H3K4me3 around ace3, ori-β, and ace1. H3K4 was also dimethylated (Figure 2B and 2C). These data showed that the gene amplification locus encoding genes for choriogenesis is euchromatic. Gene amplification was be induced by ecdysone signaling (Figure 2B and C). We observed a correlation between gene amplification-associated H3K4me3 and TRR loading in fc cells (Figure 2B and 2C). To investigate the biological significance of H3K4me3, we overexpressed H3K4 demethylase Lsd1 or Lid in fc cells. Many groups have isolated H3K4 demethylases and trimethylases in the same species (52-60). In Drosophila, Lsd1 is a dimethyl histone H3K4 demethylase (58) and Lid is a trimethyl histone H3K4 demethylase (61-63). Lsd1 or Lid overexpression in females caused sterility (Figure 3A and 3B). By contrast, females expressing Lid jmjC*, which has a mutation in its active site, or Cdc6 or GFP (28) were normal. These data suggest that H3K4me3 is essential for gene amplification.

Orc1 is the key player in initiation because it binds to chromatin via its BAH domain and is degraded in a cell cycle-dependent manner (21, 30, 35, 64). For functional ORC formation, Orc1 requires the Orc core complex, Orc2–5 (9, 29, 65, 66). Orc1 is loaded on gene amplification origins (Figure 2A and B). These data suggest that developmental signals can regulate gene amplification. We speculate that gene amplification this reaction is coupled to transcription.

In summary, the data suggest that ecdysone signaling determines which origin initiates DNA replication (Figure 4).

Figure 4

Schematic representation of the putative mechanism by which ecdysone signals could regulate chorion gene amplification. EcR: Ecdyson receptor, USP: RXR ortholog, Ultraspiracle, TRR: Histone H3K4 methyltransferase, ORC: Origin recognition complex

5.1. Ecdyson signals could regulate chorion gene amplification in Drosophila development

Here, we showed that EcR regulates chorion gene amplification through the activity of the H3K4 trimethylase TRR. Overexpression of H3K4 demethylases Lsd1 and Lid, but not the jmjC mutant Lid jmjC* (63), led to female sterility. Because EcR, TRR (26, 30), and Orc2 mutants experience a growth defect before chorion gene amplification, EcR signaling may direct gene amplification. The heterodimer partner USP was identified originally as chorion factor 1, which binds to the chorion s15 cis-regulatory element (2, 67, 68). This elementincludes ori-β and the putative EcR-binding sites (Figure 2A). We propose that EcR-USP-TRR binds to the region between S18 and ori-β.

We previously showed that transcription factors regulate ORC loading and initiation of DNA replication via chromatin modifications in S. cerevisiae (69) and Drosophila (30). The initiation of gene amplification is linked to histone H3 and H4 hyperacetylation and H1 phosphorylation in Drosophila (70). Indeed, in Drosophila fc cells, binding of Rpd3 or Polycomb proteins to origins decreases their initiation activity, whereas binding of the Hat1 homolog, Chameau acetyltransferase, increases origin activity (1). The assay used an artificial technique because of fusing these proteins to the Gal4 DNA binding domain. Then, the situation in vivo remains unclear. dE2F-dDP-Rbf interacts with DmOrc and dE2F1, and DmOrc binds to chorion gene amplification loci in vivo (15). Because the authors did not identify the E2F-binding site or the mutation disrupting the interaction, it is unknown whether they bind directly or indirectly.

EcR isoforms are functionally distinct. When early genes are expressed in tissues, the EcR-A isoform is dominant. The other EcR isoform, EcR-B1, is the predominant isoform in both the imaginal and larval cells of the larval midgut (71). What induces differences in expression and function? Bender et al. suggested that tissue-specific coactivators, such as TRR, may provide the link between the transcription machinery for a given gene and a particular EcR isoform (31). If this is the case, it would be the coactivator that determines which EcR isoform is used to activate the gene. These might be akin to the plethora of putative coactivators recently found for vertebrate nuclear receptors (31, 72) (Figure 4).

In mammals, many transcription factors are proto-oncogenes, including c-Jun, c-Myb, and c-Myc (20, 73). Their oncogenicity is thought to be due to dysregulation of the transcription that they promote. By contrast, we speculate that it is the dysregulation of replication caused by the multifunctionality of these transcription factors that contributes to their oncogenic potential. This speculation is supported by previous reports (20, 74). c-Jun homologhas been shown to regulate ORC loading in S. cerevisiae (69) and a c-Jun ortholog, Gcn4, promotes ORC loading. In Drosophila, a myb gene mutant induces a defect in S-phase progression in several tissues. c-Myc modulates DNA replication origin activity through the regulation of Cdc45 loading (74, 75). We previously propose that the DNA replication machinery contributes to development (28, 77). Changes in the space- and time-controlled process of development can lead to dys-regulated DNA synthesis, checkpoint activation, genomic instability, and/or cell death.

In America, 12.1% of women aged 15–44 have impaired fecundity and 7.3 million (12.0%) have never used infertility services, and 6.7% of married women aged 15–44 are infertile (77).

The life cycle of Drosophila is short. Screening strategies using these flies could potentially lead to the development of drugs for the treatment of sterility.


We dedicate this paper to M. Asano. We thank N. Dyson (Harvard Medical School, Boston, USA), R.N. Eisenman (Fred Hutchinson Cancer Research Center, Seattle, USA), and M. Asano for flies harboring UAS-Lsd, UAS-Lid, and UAS-Lid jmjC*. We thank M. Asano for technical advice and gifts of orc1+-promoter-Orc1-GFP-9myc, UAS-Orc2-GFP-9myc, UAS-Orc1-GFP-9myc, UAS-Cdc6-GFP-9myc, and UAS-GFP. We dedicate this paper to M. Asano (The Ohio State University). We thank Dr. Tadashi Uemura (Kyoto University) and members of his laboratory for their dedicated support and helpful assistance. This work was partially supported by the Japanese Leukemia Research Fund. H.K. was supported by a KIT VL grant and the Memorial Fund on the 44th Annual Meeting of the Japan Society for Clinical Laboratory Automation and The Motoo Kimura Trust Foundation for the Promotion of Evolutionary Biology. This manuscript has been released as a Pre-Print (78).

AggarwalB. DCalvi.B. RChromatin regulates origin activity in Drosophila follicle cellsNature.20044306997372376DOI: 10.1038/nature02694
ChristiansonA. M. KhouryKingD. LHatzivassiliouECasasJ. EHallenbeckP. LNikodemV. MMitsialisS. AKafatos.F. CDNA binding and heteromerization of the Drosophila transcription factor chorion factor 1/ultraspiracleProc. Natl. Acad. Sci. USA.199289231150311507DOI: 10.1073/pnas.89.23.11503
RoyzmanIOrr-Weaver.T. LS phase and differential DNA replication during Drosophila oogenesisGenes cells.19983767776DOI: 10.1046/j.1365-2443.1998.00232.x
LeeL. AOrr-Weaver.T. LRegulation of cell cycles in Drosophila development: intrinsic and extrinsic cuesAnnu. Rev. Genet199837545578DOI: 10.1146/annurev.genet.37.110801.143149
ClaycombJ. MBenasuttiMBoscoGFengerD. DOrr-Weaver.T. LGene amplification as a developmental strategy: isolation of two developmental amplicons in DrosophilaDev. Cell20046145155DOI: 10.1016/S1534-5807(03)00398-8
LandisGKellyRSpradlingA. CTowerJThe k43 gene, required for chorion gene amplification and diploid cell chromosome replication, encodes the Drosophila homolog of yeast origin recognition complex subunit 2Proc. Natl. Acad. Sci. USA.19979438883892DOI: 10.1073/pnas.
LoupartM. LKrauseS. AHeck.M. S. ASMAberrant replication timing induces defective chromosome condensation in Drosophila ORC2 mutantsCurrent. Biol.2000102415471556DOI: 10.1016/S0960-9822(00)00844-7
Landis G Tower. J The Drosophila chiffon gene is required for chorion gene amplification, and is related to the yeast Dbf4 regulator of DNA replication and cell cycle Development. 1999 126 4281 4293
SchwedGMayNPecherskyYCalvi.B. RDrosophila minichromosome maintenance 6 is required for chorion gene amplification and genomic replicationMol. Cell Biol.200213607620DOI: 10.1091/mbc.01-08-0400
Pflumm M. F Botchan. M. R Orc mutants arrest in metaphase with abnormally condensed chromosomes Development 2001 128 1697 1707
BalasovMHuijbregtsR. PChesnokovII. :Functional analysis of an Orc6 mutant in DrosophilaProc. Natl. Acad. Sci. USA.2009106261067210677DOI: 10.1073/pnas.0902670106
RoymanIAustinR. JBascoGBellS. POrr-Weaver.T. LORC localization inDrosophila follicle cells and the effects of mutations in dE2F and dDP. Genes & Dev. 199913827840DOI: 10.1101/gad.
Cayirlioglu P Bonnette P. C Dickson M. R Duronio. R. J Drosophila E2f2 promotes the conversion from genomic DNA replication to gene amplification in ovarian follicle cells Development 2001 128 5085 5098
CayirliogluPWardW. OKeyS. C. SDuronio.R. JTranscriptional repressor functions of Drosophila E2F1 and E2F2 cooperate to inhibit genomic DNA synthesis in ovarian follicle cellsMol. Cell. Biol20032321232134DOI: 10.1128/mcb.
BascoGDuWOrr-Weaver.T. LDNA replication control through interaction of E2F-RB and the origin recognition complexNature Cell Biol.20013289295DOI: 10.1038/35060086
BeallE. LManakJ. RZhouSBellMLipsickJ. SBotchan.M. RRole for a Drosophila Myb-containing protein complex in site-specific DNA replicationNature2002420833837DOI: 10.1038/nature01228
BeallE. LBellMGeorletteDBotchan.M. RDm-myb mutant lethality in Drosophila is dependent upon mip130: positive and negative regulation of DNA replicationGenes & Dev20041816671680DOI: 10.1101/gad.1206604
LuLZhangHTower.JFunctionally distinct, sequence-specific replicator and origin elements are required for Drosophila chorion gene amplificationGenes & Dev.200115134146DOI: 10.1101/gad.822101
ZhangHTower.JSequence requirements for function of the Drosophila chorion gene locus ACE3 replicator and ori-beta origin elementsDevelopment200413120892099DOI: 10.1242/dev.01064
KohzakiHMurakami.YTranscription factors and DNA replication origin selectionBioEssays20052711071116DOI: 10.1002/bies.950131202
AsanoM.WhartonR. P(1999) E2F mediates developmental and cell cycle regulation of ORC1 in DrosophilaEMBO J.1824352448DOI: 10.1093/emboj/
ParkS. YAsano.MAn orc1 allele with a mutated APC motif is female sterile with amplification defectCell Cycle.2012111528282832DOI: 10.4161/cc.21168
ArakiMWhartonR. PTangZAsano.MDegradation of origin recognition complex large subunit by the anaphase-promoting complex in Drosophila. EMBo J.2003222261156126DOI: 10.1093/emboj/cdg573
ArakiMYuHAsanoMM.: A novel motif governs APC-dependent degradation of Drosophila ORC1 in vivoGenes Dev.20051924582465DOI: 10.1101/gad.1361905
ParkS. YAsano.MThe origin recognition complex is dispensable for endoreplication in DrosophilaProc. Natl. Acad. Sci. USA.2008105341234312348DOI: 10.1073/pnas.0805189105
SedkovYBenesJBergerJ. RRikerK. MTillibSJonesR. SMazoAMolecular genetic analysis of the Drosophila trithorax-related gene which encodes a novel SET domain proteinMech. Dev.199982171179DOI: 10.1016/S0925-4773(98)00246-9
SedkovYChoEPetrukSCherbasLSmithS. TJonesR. SCherbasPCanaaniEJaynesJ. BMazo.AMethylation at lysine 4 of histone H3 in ecdysone-dependent development of DrosophilaNature20034267883DOI: 10.1038/nature02080
KohzakiHAsanoMMurakami.YDNA replication machinery is required for development in DrosophilaFront Biosci, Landmark 201823493505DOI: 10.2741/4601
AustinR. JOrr-WeaverT. LBell.S. PDrosophila ORC specifically binds to ACE3, an origin of DNA replication control elementGenes & Dev.19991326392649DOI: 10.1101/gad.13.20.2639
KohzakiHAsano.MAttempt of chromosome and genetic testing detection using ChIP assayFront Biosci, Scholar201682298302DOI: 10.2741/s463
BenderMImamF. BTalbotW. SGanetzkyBHogness.D. SDrosophila ecdysone receptor mutations reveal functional differences among receptor isoformsCell199791777788DOI: 10.1016/S0092-8674(00)80466-3
WhiteK. PHurbanPWatanabeTHogness.D. SCoordination of Drosophila metamorphosis by two ecdysone-induced nuclear receptorsScience1997276114117DOI: 10.1126/science.276.5309.114
Buszczak M Freeman M. R Carlson J. R Bender M Cooley L Segraves. W. A Ecdysone response genes govern egg chamber development during mid-oogenesis in Drosophila Development 1999 126 4581 4589
Tzolovsky G Deng W. M Schlitt T Bownes. M The function of the broad-complex during Drosophila melanogaster oogenesis Genetics 1999 153 1371 1383
Schepers.A(2001) Human origin recognition complex binds to the region of the latent origin of DNA replication of Epstein-Barr virusThe EMBO J2001201645884602DOI: 10.1093/emboj/20.16.4588
Dej K. J Spradling. A. C The endocycle controls nurse cell polytene chromosome structure during Drosophila oogenesis Development 1999 126 293 303
WhiteK. PRifkinS. AHurbanPHogness.D. SMicroarray analysis of Drosophila development during metamorphosisScience199928621792184DOI: 10.1126/science.286.5447.2179
Carney G. E Bender. M The Drosophila ecdysone receptor (EcR) gene is required maternally for normal oogenesis Genetics 2000 154 1203 1211
ArbeitmanM. NHogness.D. SMolecular chaperones activate the Drosophila ecdysone receptor, an RXR heterodimerCell.200010116777DOI: 10.1016/S0092-8674(00)80624
LiT. RWhite.K. PTissue-specific gene expression and ecdysone-regulated genomic networks in DrosophilaDev. Cell200355972DOI: 10.1016/S1534-5807(03)00192-8
DavisM. BCarneyG. ERobertsonA. EBender, M.: Phenotypic analysis of EcR-A mutants suggests that EcR isoforms have unique functions during Drosophila developmentDev. Biol.2005282385396DOI: 10.1016/j.ydbio.2005.03.019
KoelleM. RTalbotW. SSegravesW. ABenderM. TCherbasPHogness.D. SThe Drosophila EcR gene encodes an ecdysone receptor, a new member of the steroid receptor superfamilyCell1991675977DOI: 10.1016/0092-8674(91)90572-G
Hall B. L Thummel. C. S The RXR homolog ultraspiracle is an essential component of the Drosophila ecdysone receptor Development 1998 125 4709 4717
GhbeishNTsaiC. CSchubigerMZhouJ. YEvansR. MMcKeown.MThe dual role of ultraspiracle, the Drosophila retinoid X receptor, in the ecdysone responseProc. Natl. Acad. Sci. USA.200198738673872DOI: 10.1073/pnas.061437798
HuXCherbasLCherbas.PTranscription activation by the ecdysone receptor (EcR/USP): identification of activation functionsMol. Endocrionol.200317716731DOI: 10.1210/me.2002-0287
LiangCSpitzerJ. DSmithH. SGerbi.S. AReplication initiates at a confined region during DNA amplification in Sciara DNA puff II/9AGenes & Dev.1993710721084DOI: 10.1101/gad.
FoulkM. SLiangCWuNBlitzblauH. GSmithHAlamDD., et al. (2006) Ecdysone induces transcription and amplification in Sciara coprophila DNA puff II/9ADev. Biol2006299151163DOI: 10.1016/j.ydbio.2006.07.018
KohzakiHMurakami.YFaster and easier chromatin immunoprecipitation assay with high sensitivityPROTEOMICS200771014DOI: 10.1002/pmic.200600283
CherbasLHuXZhimulevIBelyaevaECherbas.PEcR isoforms in Drosophila: testing tissue-specific requirements by targeted blockade and rescueDevelopment2003130271284DOI: 10.1242/dev.00205
MetzgerESchüle.RThe expanding world of histone lysine demethylasesNature Str. Mol. Biol.200714252254DOI: 10.1038/nsmb0407-252
IIIR. J. SimsReinberg.DHistone H3 Lys 4 methylation: caught in a bind?Genes & Dev20062027792786DOI: 10.1101/gad.1468206
ShiY. J.LanFMatsonCMulliganCWhetstinePColeJ.R.P.A., et al. Histone demethylation mediated by the nuclear amine oxidase homolog LSD1Cell2004119941953DOI: 10.1016/j.cell.2004.12.012
ShiY. JMatsonCLanFIwaseSBabaTShiYY. (2005) Regulation of LSD1 histone demethylase activity by its associated factorsMol. Cell200519857864DOI: 10.1016/j.molcel.2005.08.027
ChristensenJAggerKCloosP. A. CPasiniDRoseSSennelsLRappsilberJHansenK. HSalciniA. EHelin.KRBP2 belongs to a family of demethylases, specific for tri-and dimethylated lysine 4 on histone 3Cell200712810631076DOI: 10.1016/j.cell.2007.02.003
LanFCollinsR. ECegliR. DeAlpatovRHortonJ. RShiXGozaniOChengXShi.YRecognition of unmethylated histone H3 lysine 4 links BHC80 to LSD1-mediated gene repressionNature20074487154718722DOI: 10.1038/nature06034
LiangGKloseR. JGardnerK. EZhang.YYeast Jhd2p is a histone H3 Lys4 trimethyl demethylaseNature Str. Mol. Biol.200714243245DOI: 10.1038/nsmb1204
SewardD. JCubberleyGKimSSchonewaldMZhangLTripetBBentley.D. LDemethylation of trimethylated histone H3 Lys4 in vivo by JARID1 JmjC proteinsNature Str. Mol. Biol.200714240242DOI: 10.1038/nsmb1200
StefanoL. DJiJ. YMoonN. SHerrADyson.NMutation of Drosophila Lsd1 disrupts H3-K4 methylation, resulting in tissue-specific defects during developmentCur. Biol200717808812DOI: 10.1016/j.cub.2007.03.068
IwaseSLanFBaylissPde la Torre-UbietaLHuarteMQiH. H.WhetstineJ. R.BonniARobertsT. M.ShiYThe X-linked mental retardation gene SMCX/JARID1C defines a family of histone H3 lysine 4 demethylasesCell200712810771088DOI: 10.1016/j.cell.2007.02.017
TahilianiMMeiPFangRLeonorTRutenbergMShimizuFLiJRaoAShiYThe histone H3K4 demethylase SMCX links REST target genes to X-linked mental retardationNature20074477144601605DOI: 10.1038/nature05823
EissenbergJ. CLeeM. GSchneiderJIlvarsonnAShiekhattarRGilatifard.AThe trithorax-group gene in Drosophila little imaginal discs encodes a trimethylated histone H3 Lys4 demethylaseNature Str. Mol. Biol.200714344346DOI: 10.1038/nsmb1217
LeeNZhangJKloseR. JErdjument-BromageHTempstPSRJones, et al. The trithorax-group protein Lid is a histone H3 trimethyl-Lys4 demethylaseNature Str. Mol. Biol.200714341343DOI: 10.1038/nsmb1216
SecombeJLiLCarlosLEisenman.R. NThe Trithorax group protein Lid is a trimethyl histone H3K4 demethylase required for dMyc-induced cell growthGenes & Dev.200721537551DOI: 10.1101/gad.1523007
AsanoMNevinsJ. RWharton.R. PEctopic E2F expression induces S phase and apoptosis in Drosophila imaginal discsGenes & Dev.1996101114221432DOI: 10.1101/gad.10.11.1422
ChesnokovIGossenMRemusDBotchan.MAssembly of functionally active Drosophila origin recognition complex from recombinant proteinsGenes & Dev.19991312891296DOI: 10.1101/gad.13.10.1289
DePamphilisM. LBlowJ. JGhoshSSahaTNoguchi et alKRegulating the licensing of DNA replication origins in metazoaCurr. Opin. Cell Biol.200618231239DOI: 10.1016/
SheaM. JKingD. LConboyM. JMarianiB. DKafatos.F. CProteins that bind to Drosophila chorion cis-regulatory elements: a new C2H2 zinc finger protein and a C2C2 steroid receptor-like componentGenes & Dev1990411281140DOI: 10.1101/gad.
MarianiB. DSheaM. JConboyM. JConboyIKing et alD. L(1996) Analysis of regulatory elements of the developmentally controlled chorion s15 promoter in transgenic DrosophilaDev. Biol.1996174115124DOI: 10.1006/dbio.1996.0056
KohzakiHItoYMurakami.YContext-dependent modulation of the replication activity of Saccharomyces cerevisiae autonomously replicating sequences by transcription factorsMol. Cell. Biol.19991974287435DOI: 10.1128/MCB.19.11.7428
HartlTBoswellCOrr-Weaver.T. LDevelopmentally regulated histone modifications in Drosophila follicle cells: initiation of gene amplification is associated with histone H3 and H4 hyperacetylation and H1 phosphorylationChromosoma2007116197214DOI: 10.1007/s00412-006-0092-2
Li T Bender. M A conditional rescue system reveals essential functions for the ecdysone receptor (EcR) geneduring molting and metamorphosis in Drosophila. Development 2000 127 13 2897 2905
MangelsdorfD. JEvans.R. MThe RXR heterodimers and orphan receptorsCell1995836841850DOI: 10.1016/0092-8674(95)90200-7
MurakamiYIto.YTranscription factors in DNA replicationFront Biosci.19994D82433DOI: 10.2741/A466
Dominguez-SolaDYingC. YGrandoriCRuggieroLChenBLiMGallowayD. AGuWGautierJDalla-Favera.R. MNon-transcriptional control of DNA replication by c-MycNature2007448445451DOI: 10.1038/nature05953
LebofskyRWalter.W. CNew Myc-anisms for DNA replication and tumorigenesis? Cancer Cell200712102103DOI: 10.1016/j.ccr.2007.07.013
KohzakiHMurakami.YDNA replication machinery contributes to development of eye inDrosophila. Fronti Biosci, Landmark201823506511DOI: 10.2741/4601
KohzakiH.AsanoM.MurakamiY.MazoA(2018) Epigenetic regulation affects gene amplification in Drosophila development. Biorxiv ( 10.1101/317123
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