Gene Symbol: stg
Description: string
Alias: 0224/06, 0245/03, 0439/22, 0730/13, 0896/05, 0967/05, 0980/06, 1083/13, 1089/08, 1143/02, 5473, CDC25, CDC25[string], CG1395, Cdc25, Cdc25[Stg], Cdc25[String], Cdc25[stg], Cdc25[string], Cdc25c, Dmel\CG1395, EP1213, S(rux)3A, STG, SY3-4, Stg, String/Cdc25, anon-EST:Liang-2.21, cdc25, cdc25[string], clone 2.21, l(3)01235, l(3)j10B9, l(3)j1D3, l(3)j1E3, l(3)j3D1, l(3)s2213, stg[cdc25], str/cdc25, string, CG1395-PA, CG1395-PB, Cdc25, String/Cdc25 phosphatase, cdc25/string, stg-PA, stg-PB, string/cdc25, suppressor of rux 3A
Species: fruit fly

Top Publications

  1. Su T, Walker J, Stumpff J. Activating the DNA damage checkpoint in a developmental context. Curr Biol. 2000;10:119-26 pubmed
    ..Gastrulation and the developmental program of string (Cdc25) gene expression, which normally regulates the timing of mitosis, occurred normally after irradiation...
  2. Sun J, Deng W. Notch-dependent downregulation of the homeodomain gene cut is required for the mitotic cycle/endocycle switch and cell differentiation in Drosophila follicle cells. Development. 2005;132:4299-308 pubmed
    ..Our data suggest that Cut functions in regulating both cell differentiation and the cell cycle, and that downregulation of Cut by Notch contributes to the mitotic cycle/endocycle switch and cell differentiation in follicle cells. ..
  3. Reis T, Edgar B. Negative regulation of dE2F1 by cyclin-dependent kinases controls cell cycle timing. Cell. 2004;117:253-64 pubmed
    ..dE2F1, in turn, positively regulates cyclin E and string/cdc25, which activate the Cdks to drive cell cycle progression...
  4. Reber A, Lehner C, Jacobs H. Terminal mitoses require negative regulation of Fzr/Cdh1 by Cyclin A, preventing premature degradation of mitotic cyclins and String/Cdc25. Development. 2006;133:3201-11 pubmed
    ..activity results in the premature degradation of the Cdk1 activators Cyclin B and Cyclin B3, and apparently of String/Cdc25 phosphatase as well. Without these activators, entry into terminal mitoses is not possible...
  5. Bashirullah A, Cooperstock R, Lipshitz H. Spatial and temporal control of RNA stability. Proc Natl Acad Sci U S A. 2001;98:7025-8 pubmed
    ..Similar mechanisms are likely to act later in development to restrict certain classes of transcripts to particular cell types within somatic cell lineages. Functions of transcript degradation and protection are discussed. ..
  6. Chen F, Archambault V, Kar A, Lio P, D Avino P, Sinka R, et al. Multiple protein phosphatases are required for mitosis in Drosophila. Curr Biol. 2007;17:293-303 pubmed
    ..found that G(2)-M progression requires Puckered, the JNK MAP-kinase inhibitory phosphatase and PP2C in addition to string (Cdc25). Strong mitotic arrest and chromosome congression failure occurred after Pp1-87B downregulation...
  7. Deng W, Althauser C, Ruohola Baker H. Notch-Delta signaling induces a transition from mitotic cell cycle to endocycle in Drosophila follicle cells. Development. 2001;128:4737-46 pubmed
    ..One target of Notch and Su(H) is likely to be the G2/M cell cycle regulator String, a phosphatase that activates Cdc2 by dephosphorylation...
  8. Sauer K, Knoblich J, Richardson H, Lehner C. Distinct modes of cyclin E/cdc2c kinase regulation and S-phase control in mitotic and endoreduplication cycles of Drosophila embryogenesis. Genes Dev. 1995;9:1327-39 pubmed
    ..Observations in cyclin A mutants implicate G2 cyclins in this regulation. Our results suggest molecular explanations for the different rules governing S phase during mitotic and endoreduplication cycles. ..
  9. Mozer B, Easwarachandran K. Pattern formation in the absence of cell proliferation: tissue-specific regulation of cell cycle progression by string (stg) during Drosophila eye development. Dev Biol. 1999;213:54-69 pubmed
    ..The cdc25 phosphatase string (stg) has been proposed to contribute to the synchronization of retinal precursors anterior to the furrow by ..

More Information


  1. Johnston L, Edgar B. Wingless and Notch regulate cell-cycle arrest in the developing Drosophila wing. Nature. 1998;394:82-4 pubmed
    ..subdomains by inducing the proneural genes achaete and scute, which downregulate the mitosis-inducing phosphatase String (Cdc25)...
  2. Milan M, Campuzano S, Garcia Bellido A. Cell cycling and patterned cell proliferation in the wing primordium of Drosophila. Proc Natl Acad Sci U S A. 1996;93:640-5 pubmed
    ..Cell cycle progression is linear rather than concentric. Clusters appear throughout the disc but with symmetries related to presumptive wing patterns, compartment boundaries, and vein clonal restrictions. ..
  3. Bhattacharya A, Baker N. The HLH protein Extramacrochaetae is required for R7 cell and cone cell fates in the Drosophila eye. Dev Biol. 2009;327:288-300 pubmed publisher
    ..A model is proposed in which Extramacrochaetae acts in parallel to or as a feed-forward regulator of the E(spl)-Complex to promote Notch signaling in particular cellular contexts. ..
  4. Wells B, Yoshida E, Johnston L. Compensatory proliferation in Drosophila imaginal discs requires Dronc-dependent p53 activity. Curr Biol. 2006;16:1606-15 pubmed
    ..Our data suggest that dp53 may carry out an ancestral function that promotes animal survival through the coordination of responses leading to compensatory growth after tissue damage. ..
  5. Jemc J, Rebay I. Identification of transcriptional targets of the dual-function transcription factor/phosphatase eyes absent. Dev Biol. 2007;310:416-29 pubmed
    ..Among the targets identified by our analysis was the cell cycle regulatory gene, string (stg), suggesting that EYA and SO may influence cell proliferation through transcriptional regulation of stg...
  6. Knoblich J, Sauer K, Jones L, Richardson H, Saint R, Lehner C. Cyclin E controls S phase progression and its down-regulation during Drosophila embryogenesis is required for the arrest of cell proliferation. Cell. 1994;77:107-20 pubmed
    ..Therefore, Drosophila cyclin E, which forms a complex with the Dmcdc2c kinase, controls progression through S phase and its down-regulation limits embryonic proliferation. ..
  7. Hayashi S. A Cdc2 dependent checkpoint maintains diploidy in Drosophila. Development. 1996;122:1051-8 pubmed
    ..These results suggest that in G2, escargot is required to maintain a high level of G2/M cdk that actively inhibits the entry into S phase. ..
  8. Meyer C, Kramer I, Dittrich R, Marzodko S, Emmerich J, Lehner C. Drosophila p27Dacapo expression during embryogenesis is controlled by a complex regulatory region independent of cell cycle progression. Development. 2002;129:319-28 pubmed
    ..The dacapo regulatory region includes many independent cis-regulatory elements. The elements that control epidermal expression integrate developmental cues that time the arrest of cell proliferation...
  9. Schaeffer V, Althauser C, Shcherbata H, Deng W, Ruohola Baker H. Notch-dependent Fizzy-related/Hec1/Cdh1 expression is required for the mitotic-to-endocycle transition in Drosophila follicle cells. Curr Biol. 2004;14:630-6 pubmed
    ..In this context, the only known cell cycle component that responds to the Notch pathway is String/Cdc25 (Stg), a G2/M cell cycle regulator...
  10. Grosskortenhaus R, Pearson B, Marusich A, Doe C. Regulation of temporal identity transitions in Drosophila neuroblasts. Dev Cell. 2005;8:193-202 pubmed
    ..We conclude that two distinct "timers" regulate neuroblast gene expression: a hunchback --> Kruppel timer requiring cytokinesis, and a Kruppel --> pdm1 --> castor timer which is cell cycle independent. ..
  11. Edgar B, Orr Weaver T. Endoreplication cell cycles: more for less. Cell. 2001;105:297-306 pubmed
  12. Shibutani S, Swanhart L, Duronio R. Rbf1-independent termination of E2f1-target gene expression during early Drosophila embryogenesis. Development. 2007;134:467-78 pubmed
    ..E2f1 protein reaccumulates in epidermal cells arrested in G1(17), and in these cells the induction of p27(Dap) activates Rbf1 to repress E2f1-target genes to maintain a stable G1 arrest. ..
  13. Inaba M, Yuan H, Yamashita Y. String (Cdc25) regulates stem cell maintenance, proliferation and aging in Drosophila testis. Development. 2011;138:5079-86 pubmed publisher
    ..Here, we show that the Cdc25 homolog String (Stg) is a crucial regulator of germline stem cells (GSCs) and cyst stem cells (CySCs) in Drosophila testis...
  14. Moshkin Y, Mohrmann L, van Ijcken W, Verrijzer C. Functional differentiation of SWI/SNF remodelers in transcription and cell cycle control. Mol Cell Biol. 2007;27:651-61 pubmed
    ..BAP mediates G(2)/M transition through direct regulation of string/cdc25. Its signature subunit, OSA, is required for directing BAP to the string/cdc25 promoter...
  15. White A, Leslie M, Calvi B, Marzluff W, Duronio R. Developmental and cell cycle regulation of the Drosophila histone locus body. Mol Biol Cell. 2007;18:2491-502 pubmed
    ..HLB foci are present in histone deletion embryos, although the MPM-2 foci are smaller, and some Lsm11 foci are not associated with MPM-2 foci, suggesting that the histone locus is important for HLB integrity. ..
  16. Grosshans J, Wieschaus E. A genetic link between morphogenesis and cell division during formation of the ventral furrow in Drosophila. Cell. 2000;101:523-31 pubmed
    ..Here we describe a novel mitotic inhibitor that acts during Drosophila gastrulation to counteract String/Cdc25, specifically in the cells that invaginate to form the mesoderm...
  17. Seher T, Leptin M. Tribbles, a cell-cycle brake that coordinates proliferation and morphogenesis during Drosophila gastrulation. Curr Biol. 2000;10:623-9 pubmed concert with another, as yet unidentified, factor to counteract the activity of the protein phosphatase Cdc25/String. In a finely tuned balance with Cdc25/String, Tribbles controls the timing of mitosis in the prospective mesoderm, ..
  18. Sibon O, Laurencon A, Hawley R, Theurkauf W. The Drosophila ATM homologue Mei-41 has an essential checkpoint function at the midblastula transition. Curr Biol. 1999;9:302-12 pubmed
    ..During early embryogenesis, however, this pathway is activated by developmental cues and is required for the transition from maternal to zygotic control of development at the MBT. ..
  19. Zielke N, Querings S, Rottig C, Lehner C, Sprenger F. The anaphase-promoting complex/cyclosome (APC/C) is required for rereplication control in endoreplication cycles. Genes Dev. 2008;22:1690-703 pubmed publisher
    ..Geminin is only abundant in cells with high CycE-Cdk2 activity, suggesting that APC/C-Fzr activity is periodically inhibited by CycE-Cdk2, to prevent relicensing in S-phase cells. ..
  20. Shermoen A, O Farrell P. Progression of the cell cycle through mitosis leads to abortion of nascent transcripts. Cell. 1991;67:303-10 pubmed
    ..We conclude that progression through mitosis causes abortion of nascent transcripts and suggest that periodic abortion of transcription contributes to regulation of expression of large genes. ..
  21. Schittenhelm R, Althoff F, Heidmann S, Lehner C. Detrimental incorporation of excess Cenp-A/Cid and Cenp-C into Drosophila centromeres is prevented by limiting amounts of the bridging factor Cal1. J Cell Sci. 2010;123:3768-79 pubmed publisher
    ..We demonstrate that the low amount of endogenous Cal1 prevents centromere expansion and mitotic kinetochore failure when Cenp-A/Cid and Cenp-C are present in excess. ..
  22. Li L, Vaessin H. Pan-neural Prospero terminates cell proliferation during Drosophila neurogenesis. Genes Dev. 2000;14:147-51 pubmed
    ..pros activity, hence, provides a critical regulatory link between neuronal lineage development and transcriptional regulation of cell cycle regulatory genes. ..
  23. Vidwans S, Su T. Cycling through development in Drosophila and other metazoa. Nat Cell Biol. 2001;3:E35-9 pubmed
    ..Here we present the various modes of cell-cycle regulation in metazoa and discuss their possible generation by a combination of universally conserved molecules and new regulatory circuits. ..
  24. Edgar B, O Farrell P. The three postblastoderm cell cycles of Drosophila embryogenesis are regulated in G2 by string. Cell. 1990;62:469-80 pubmed
    The string (stg) locus of Drosophila encodes a factor that is thought to trigger mitosis by activating the p34cdc2 protein kinase...
  25. Spradling A, Rubin G. Transposition of cloned P elements into Drosophila germ line chromosomes. Science. 1982;218:341-7 pubmed
    ..Thus P elements can efficiently and selectively transpose from extrachromosomal DNA to the DNA of germ line chromosomes in Drosophila embryos. These observations provide the basis for efficient DNA-mediated gene transfer in Drosophila. ..
  26. Spana E, Doe C. The prospero transcription factor is asymmetrically localized to the cell cortex during neuroblast mitosis in Drosophila. Development. 1995;121:3187-95 pubmed
    ..The asymmetric cortical localization of prospero at mitosis is a mechanism for rapidly establishing distinct sibling cell fates in the CNS and possibly other tissues. ..
  27. Thomas B, Gunning D, Cho J, Zipursky L. Cell cycle progression in the developing Drosophila eye: roughex encodes a novel protein required for the establishment of G1. Cell. 1994;77:1003-14 pubmed
    ..rux is suppressed by mutations in genes that promote cell cycle progression (i.e., cyclin A and string) and enhanced by mutations in genes that promote differentiation (i.e., Ras1 and Star)...
  28. Dawson I, Roth S, Akam M, Artavanis Tsakonas S. Mutations of the fizzy locus cause metaphase arrest in Drosophila melanogaster embryos. Development. 1993;117:359-76 pubmed
    ..In the ventral epidermis, if cells are prevented from entering mitosis by using a string mutation, cell death is prevented and the ability to differentiate ventral epidermis is restored in fizzy; string ..
  29. Milan M, Campuzano S, Garcia Bellido A. Cell cycling and patterned cell proliferation in the Drosophila wing during metamorphosis. Proc Natl Acad Sci U S A. 1996;93:11687-92 pubmed
    ..The final number of cells of the wing is fixed independently of experimental perturbations that alter the cell division schedule. These results are discussed in the context of a model of wing morphogenesis. ..
  30. Su T, Parry D, Donahoe B, Chien C, O Farrell P, Purdy A. Cell cycle roles for two 14-3-3 proteins during Drosophila development. J Cell Sci. 2001;114:3445-54 pubmed
    ..Using mutants of cyclins, Cdk1 and Cdc25(string) to manipulate Cdk1 activity, we found that the localization of 14-3-3 proteins is coupled to Cdk1 activity and ..
  31. Prober D, Edgar B. Ras1 promotes cellular growth in the Drosophila wing. Cell. 2000;100:435-46 pubmed
    ..We propose that Ras primarily promotes growth and that growth is coupled to G1/S progression via cyclin E. Interestingly, upregulation of growth by Ras did not deregulate G2/M progression or a developmentally regulated cell cycle exit. ..
  32. Klebes A, Knust E. A conserved motif in Crumbs is required for E-cadherin localisation and zonula adherens formation in Drosophila. Curr Biol. 2000;10:76-85 pubmed
    ..This scaffold mediates the localisation and stabilisation of the zonula adherens component DE-cadherin, a crucial component for the maintenance of epithelial cell polarity and tissue integrity. ..
  33. Knoblich J, Lehner C. Synergistic action of Drosophila cyclins A and B during the G2-M transition. EMBO J. 1993;12:65-74 pubmed
    ..However, mitotic spindles are clearly abnormal and progression through mitosis is delayed in these cyclin B deficient embryos. ..
  34. Sibon O, Stevenson V, Theurkauf W. DNA-replication checkpoint control at the Drosophila midblastula transition. Nature. 1997;388:93-7 pubmed
    ..This delay may allow both completion of S phase and transcription of genes that initiate the switch to zygotic control of embryogenesis. ..
  35. Pignoni F, Zipursky S. Induction of Drosophila eye development by decapentaplegic. Development. 1997;124:271-8 pubmed
    ..In addition, Dpp positively controls its own expression and suppresses wingless transcription. In contrast to the wing disc, Dpp does not appear to be the principal mediator of Hedgehog function in the eye. ..
  36. de Nooij J, Letendre M, Hariharan I. A cyclin-dependent kinase inhibitor, Dacapo, is necessary for timely exit from the cell cycle during Drosophila embryogenesis. Cell. 1996;87:1237-47 pubmed
    ..Thus, dap functions during embryogenesis to achieve a precisely timed exit from the cell cycle. ..
  37. Lopes C, Casares F. hth maintains the pool of eye progenitors and its downregulation by Dpp and Hh couples retinal fate acquisition with cell cycle exit. Dev Biol. 2010;339:78-88 pubmed publisher
    ..characterized by a relatively long G2 phase, which makes them prone to enter mitosis; hth represses the burst of string/cdc25 expression that precedes G1 arrest, and also the early expression of the proneural gene atonal...
  38. Negre N, Ghysen A, Martinez A. Mitotic G2-arrest is required for neural cell fate determination in Drosophila. Mech Dev. 2003;120:253-65 pubmed
    ..We forced G2 cells to enter mitosis by overexpression of string, the Drosophila homologue of the cdc25 gene...
  39. Edgar B, Sprenger F, Duronio R, Leopold P, O Farrell P. Distinct molecular mechanism regulate cell cycle timing at successive stages of Drosophila embryogenesis. Genes Dev. 1994;8:440-52 pubmed
    The conserved regulators of cell cycle progression--Cyclins, Cdc2 kinase, and String phosphatase (Cdc25)--accommodate multiple modes of regulation during Drosophila embryogenesis...
  40. Baonza A, Murawsky C, Travers A, Freeman M. Pointed and Tramtrack69 establish an EGFR-dependent transcriptional switch to regulate mitosis. Nat Cell Biol. 2002;4:976-80 pubmed
    ..This 'second mitotic wave' is triggered by EGFR signalling and depends on expression of String, the Drosophila homologue of Cdc25 phosphatase, the ultimate regulator of mitosis in all eukaryotic cells...
  41. Buttitta L, Katzaroff A, Perez C, de la Cruz A, Edgar B. A double-assurance mechanism controls cell cycle exit upon terminal differentiation in Drosophila. Dev Cell. 2007;12:631-43 pubmed
    ..In other cell types, however (e.g., wing epithelial cells), unknown mechanisms inhibit E2F and Cyclin/Cdk activity in parallel to enforce permanent cell cycle exit upon terminal differentiation. ..
  42. Shcherbata H, Althauser C, Findley S, Ruohola Baker H. The mitotic-to-endocycle switch in Drosophila follicle cells is executed by Notch-dependent regulation of G1/S, G2/M and M/G1 cell-cycle transitions. Development. 2004;131:3169-81 pubmed
    ..These genes include the G2/M regulator Cdc25 phosphatase, String; a regulator of the APC ubiquitination complex Hec/CdhFzr and an inhibitor of the CyclinE/CDK complex, Dacapo...
  43. Neufeld T, de la Cruz A, Johnston L, Edgar B. Coordination of growth and cell division in the Drosophila wing. Cell. 1998;93:1183-93 pubmed
    ..of the transcriptional regulator dE2F increased expression of the S- and M-phase initiators Cyclin E and String (Cdc25), thereby accelerating cell proliferation...
  44. Edgar B, Datar S. Zygotic degradation of two maternal Cdc25 mRNAs terminates Drosophila's early cell cycle program. Genes Dev. 1996;10:1966-77 pubmed
    ..Here we show that this transition requires degradation of two maternal mRNAs, string and twine, which encode Cdc25 phosphatases...
  45. Kumagai A, Dunphy W. The cdc25 protein controls tyrosine dephosphorylation of the cdc2 protein in a cell-free system. Cell. 1991;64:903-14 pubmed
    ..Genetic studies have demonstrated that the cdc25 protein activates the cdc2 protein kinase once DNA replication has been completed...
  46. Baker N, Yu S. The EGF receptor defines domains of cell cycle progression and survival to regulate cell number in the developing Drosophila eye. Cell. 2001;104:699-708 pubmed
    ..Through proliferation and survival control, such signals couple the total number of uncommitted cells being generated to the neural patterning of the retina. ..
  47. Edgar B, Lehner C. Developmental control of cell cycle regulators: a fly's perspective. Science. 1996;274:1646-52 pubmed
  48. Wodarz A, Gonzalez C. Connecting cancer to the asymmetric division of stem cells. Cell. 2006;124:1121-3 pubmed
    ..This work suggests a mechanism by which loss of polarity in stem cells may lead to tumorigenesis. ..
  49. Kylsten P, Saint R. Imaginal tissues of Drosophila melanogaster exhibit different modes of cell proliferation control. Dev Biol. 1997;192:509-22 pubmed
    ..melanogaster homologue of the Schizosaccharomyces pombe p80cdc25 phosphatase. In a second study, string transcriptional regulation was also shown to be important for G2-phase regulation in eye disk cells posterior to ..
  50. Lehman D, Patterson B, Johnston L, Balzer T, Britton J, Saint R, et al. Cis-regulatory elements of the mitotic regulator, string/Cdc25. Development. 1999;126:1793-803 pubmed
    Mitosis in most Drosophila cells is triggered by brief bursts of transcription of string (stg), a Cdc25-type phosphatase that activates the mitotic kinase, Cdk1 (Cdc2)...
  51. Myers F, Francis Lang H, Newbury S. Degradation of maternal string mRNA is controlled by proteins encoded on maternally contributed transcripts. Mech Dev. 1995;51:217-26 pubmed
    In Drosophila, maternal string mRNAs are stable for the first few hours of development, but undergo specific timed degradation at the cellularisation stage...
  52. Bashirullah A, Halsell S, Cooperstock R, Kloc M, Karaiskakis A, Fisher W, et al. Joint action of two RNA degradation pathways controls the timing of maternal transcript elimination at the midblastula transition in Drosophila melanogaster. EMBO J. 1999;18:2610-20 pubmed
    ..The second pathway is activated 2 h after fertilization and functions together with the maternal pathway to ensure that transcripts are degraded by the MBT. ..
  53. Edgar B, O Farrell P. Genetic control of cell division patterns in the Drosophila embryo. Cell. 1989;57:177-87 pubmed
    ..Mutations at the string (stg) locus cause cell-cycle arrest during this transition, in G2 of interphase 14, yet do not arrest other ..
  54. Jacobs H, Knoblich J, Lehner C. Drosophila Cyclin B3 is required for female fertility and is dispensable for mitosis like Cyclin B. Genes Dev. 1998;12:3741-51 pubmed
    ..However, both are required for female fertility and Cyclin B also for male fertility. ..
  55. Myster D, Duronio R. To differentiate or not to differentiate?. Curr Biol. 2000;10:R302-4 pubmed
    ..Equally important is regulated withdrawal from the cell cycle to allow cells to differentiate. Recent evidence supports a direct link between transcriptional regulation of the cell cycle machinery and cell differentiation. ..
  56. Hartenstein V, Posakony J. Sensillum development in the absence of cell division: the sensillum phenotype of the Drosophila mutant string. Dev Biol. 1990;138:147-58 pubmed
    We have investigated sensillum development in Drosophila embryos homozygous for mutations in the locus string (stg). In these embryos, cell division is blocked following blastoderm formation...
  57. Isshiki T, Pearson B, Holbrook S, Doe C. Drosophila neuroblasts sequentially express transcription factors which specify the temporal identity of their neuronal progeny. Cell. 2001;106:511-21 pubmed
    ..We propose that Hunchback and Krüppel control early-born temporal identity in neuroblast cell lineages. ..