FlyBase Allele Report: Dmel\Iswi[2]

Iswi² homozygous third instar larvae show a decreased mitotic index in the brain lobes; C4da neurons show decreased dendrite complexity (decreased dendrite length and branch number); there are tilling defects between C4da neurons ddaC and v'ada.

(Li et al., 2021)

Iswi¹/Iswi² transheterozygote males display defects in the morphology of the polytene chromosome X in larval salivary glands. The X chromosome is shorter and more compact compared to wild-type.

(Mengoli et al., 2014)

Flies containing eyes homozygous for Iswi² (generated using the EGUF technique) have rough eyes of reduced size.

Polytene chromosomes of Iswi¹/Iswi² male larvae show condensation defects, particularly of the X chromosome.

(Onorati et al., 2011)

Flies containing homozygous eyes in an otherwise heterozygous background (generated using the EGUF technique) have rough eyes which also show colour variegation and loss of cell identity (bristles grow in parts of the eye territory normally occupied by photoreceptors). Loss of ommatidia boundaries and orientation and reduced number of photoreceptors are seen.

Mutant imaginal disc cell populations show changes in cell cycle profiles compared to wild type, showing a significant decrease of the G[[1]] and G[[2]]/M peaks and an increase in the pre-G[[1]] peak.

Mutant larval brain neuroblast cell populations show changes in cell cycle profiles compared to wild type, with a small but reproducible increase in the G[[2]]/M peak and a shorter S phase than normal.

(Arancio et al., 2010)

The male X polytene chromosome is decondensed in salivary glands of Iswi¹/Iswi² larvae, although the banding pattern is usually retained.

(Siriaco et al., 2009)

Expression of Iswi^{K159R.Scer\UAS.T:Ivir\HA1} under the control of Scer\GAL4^ey.PH in an otherwise wild-type background results in flies with rough and reduced eyes. The severity of the phenotype is increased when Iswi^{K159R.Scer\UAS.T:Ivir\HA1} is expressed under the control of Scer\GAL4^ey.PH in an Iswi² background.

(Burgio et al., 2008)

Iswi¹/Iswi² animals often survive until the early to mid pupal stages, and have slightly misshapen wing discs at the late third larval instar.

(Liu et al., 2008)

The X polytene chromosome is decondensed in male Iswi¹/Iswi² larvae but not in female Iswi¹/Iswi² larvae.

Mitotic chromosomes prepared from neuroblasts of Iswi¹/Iswi² third instar larvae are indistinguishable from wild type.

Animals expressing Iswi^{K159R.Scer\UAS.T:Ivir\HA1} under the control of Scer\GAL4^da.G32 and derived from Iswi²/+ females survive until late larval stages at 18[o]C but do not complete embryogenesis at 25[o]C. At 25[o]C, the embryos show defects in chromosome condensation and in the organisation of the mitotic spindle as early as nuclear cycle 12.

(Corona et al., 2007)

Iswi² mutants have a high incidence of melanotic tumours and an increased number of larval hemocytes.

(Ragab, 2006)

Iswi²/+ flies exhibit a wild-type number of dorsocentral bristles on the heminotum (2.0 per heminotum).

(Vanolst et al., 2005)

96 % of clones of Iswi² homozygous female germ-line stem cells are lost from their stem cell niche by 17 days after induction, compared to only 35% of wild-type clones. The division rate of Iswi² homozygous female germ-line stem cells is around 40% of wild-type, but these mutant cells show no significant increase in apoptosis. Iswi² homozygous clone follicle stem cells exhibit only a slightly increased rate of loss from their stem cell niche in the ovary compared to wild-type.

(Xi and Xie, 2005)

The circulating hemocyte cell number in hemolymph isolated from Iswi¹/Iswi² mutants is increased considerably with respect to wild-type animals, having about 12500 per ul^-1, compared to about 4500 in wild-type.

(Badenhorst et al., 2002)

The X chromosome is grossly abnormal in salivary gland polytene chromosome preparations from homozygous male larvae, having a bloated appearance and an almost complete loss of the characteristic banding pattern.

All chromosomes appear normal in salivary gland polytene chromosome preparations from homozygous female larvae.

(Corona et al., 2002)

Heterozygotes are viable and phenotypically normal. Hemizygotes die during late larval or early pupal development and show no obvious homeotic transformations or other pattern defects. Homozygous clones can be observed in all body segments, although the size and frequency of clones in the genitalia, head and thoracic segments is reduced compared to controls. No homeotic transformations or other defects are seen in the clones. Germline clonal analysis indicates that loss of maternal Iswi⁺ function blocks oogenesis at an early stage; females carrying homozygous germline clones are not fertile. The structure of the polytene X chromosome of male Iswi¹/Iswi² larvae is much shorter and broader than normal. This alteration in structure of the X chromosome is highly penetrant and is never seen in female Iswi¹/Iswi² larvae. The polytene autosomes are often thinner than normal in both male and female mutant larvae. The structure of mitotic chromosomes of hemizygous larvae appears relatively normal.

(Deuring et al., 2000)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Enhanced by

Statement

Reference

Iswi² has visible | somatic clone phenotype, enhanceable by Acf¹

(Arancio et al., 2010)

Iswi² has visible | somatic clone phenotype, enhanceable by E(bx)^Nurf301-2

(Arancio et al., 2010)

Suppressed by

Statement

Reference

Iswi² has decreased body size | third instar larval stage phenotype, suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has decreased body size | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has decreased body size | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has abnormal neuroanatomy | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has decreased occurrence of cell division | third instar larval stage phenotype, suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has visible | third instar larval stage phenotype, suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has visible | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has visible | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^elav.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi²/Iswi¹ has lethal | larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PI/lncRNA:Hsrω^RNAi.Sym.UAS

(Onorati et al., 2011)

Iswi² has visible | somatic clone phenotype, suppressible by lncRNA:Hsrω^RNAi.Sym.UAS/Scer\GAL4^ey.PH

(Onorati et al., 2011)

Iswi² has visible | somatic clone phenotype, suppressible by ttk^EP3314/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has visible | somatic clone phenotype, suppressible by mbf1^EP3684/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has visible | somatic clone phenotype, suppressible by eff^EP3627/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has visible | somatic clone phenotype, suppressible by wun[+]/wun^PBacF48

(Arancio et al., 2010)

Iswi² has abnormal mitotic cell cycle phenotype, suppressible by casp^PBacG75α

(Arancio et al., 2010)

Iswi² has abnormal mitotic cell cycle phenotype, suppressible by wun^PBacF48

(Arancio et al., 2010)

Iswi² has abnormal mitotic cell cycle phenotype, suppressible by eff^EP3627/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has abnormal mitotic cell cycle phenotype, suppressible by ttk^EP3314/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has abnormal mitotic cell cycle phenotype, suppressible by mbf1^EP3684/Scer\GAL4^ey.PH

(Arancio et al., 2010)

NOT suppressed by

Statement

Reference

Iswi² has abnormal neuroanatomy | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has abnormal neuroanatomy | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has decreased occurrence of cell division | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has decreased occurrence of cell division | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has neoplasia phenotype, non-suppressible by Df(2R)ED3921

(Ragab, 2006)

Suppressor of

Statement

Reference

Iswi[+]/Iswi² is a suppressor of visible | adult stage phenotype of Marcal1^UAS.cBa, Scer\GAL4^Tub.PU

(Morimoto et al., 2016)

Iswi[+]/Iswi² is a suppressor of visible | adult stage phenotype of Hsap\SMARCAL1^UAS.cBa, Scer\GAL4^Bx-MS1096

(Morimoto et al., 2016)

Other

Statement

Reference

Iswi²/Iswi¹, Scer\GAL4^Act5C.PI, lncRNA:Hsrω^RNAi.Sym.UAS has lethal | pharate adult stage phenotype

(Onorati et al., 2011)

Acf[+]/Acf⁵, Iswi²/Iswi¹ has abnormal developmental rate phenotype

(Liu et al., 2008)

Phenotype Manifest In

Enhanced by

Statement

Reference

Iswi² has eye | somatic clone phenotype, enhanceable by Acf¹

(Arancio et al., 2010)

Iswi² has eye | somatic clone phenotype, enhanceable by E(bx)^Nurf301-2

(Arancio et al., 2010)

Suppressed by

Statement

Reference

Iswi² has embryonic/larval brain | third instar larval stage phenotype, suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has embryonic/larval brain | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has embryonic/larval brain | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has larval dorsal multidendritic neuron ddaC | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has larval ventral multidendritic neuron vdaA | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi² has dendrite | third instar larval stage phenotype, suppressible | partially by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^UAS.cGa

(Li et al., 2021)

Iswi²/Iswi¹ has polytene chromosome | male limited phenotype, suppressible by lncRNA:Hsrω^RNAi.Sym.UAS/Scer\GAL4^ey.PH

(Onorati et al., 2011)

Iswi² has eye | somatic clone phenotype, suppressible by lncRNA:Hsrω^RNAi.Sym.UAS/Scer\GAL4^ey.PH

(Onorati et al., 2011)

Iswi² has eye | somatic clone phenotype, suppressible by ttk^EP3314/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has eye | somatic clone phenotype, suppressible by mbf1^EP3684/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has eye | somatic clone phenotype, suppressible by eff^EP3627/Scer\GAL4^ey.PH

(Arancio et al., 2010)

Iswi² has eye | somatic clone phenotype, suppressible by wun[+]/wun^PBacF48

(Arancio et al., 2010)

Iswi² has X chromosome | male phenotype, suppressible by mle¹

(Corona et al., 2002)

NOT suppressed by

Statement

Reference

Iswi² has larval dorsal multidendritic neuron ddaC | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has larval ventral multidendritic neuron vdaA | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has dendrite | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^R592Q.UAS

(Li et al., 2021)

Iswi² has larval dorsal multidendritic neuron ddaC | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has larval ventral multidendritic neuron vdaA | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has dendrite | third instar larval stage phenotype, non-suppressible by Scer\GAL4^Act5C.PU/Hsap\SMARCA5^{del268-319.UAS}

(Li et al., 2021)

Iswi² has embryonic/larval hemocyte | increased number phenotype, non-suppressible by Df(2R)ED3921

(Ragab, 2006)

Enhancer of

Statement

Reference

Iswi[+]/Iswi² is an enhancer of dorsal appendage | maternal effect phenotype of EcR^{B1-ΔC655.F645A.UAS}, Scer\GAL4^slbo.2.6

(Badenhorst et al., 2005)

Iswi² is an enhancer of dorsocentral bristle phenotype of pnr^VX1

(Vanolst et al., 2005)

Iswi² is an enhancer of dorsocentral bristle phenotype of Chi^E

(Vanolst et al., 2005)

Suppressor of

Statement

Reference

Iswi[+]/Iswi² is a suppressor of wing vein | adult stage phenotype of Marcal1^UAS.cBa, Scer\GAL4^Tub.PU

(Morimoto et al., 2016)

Iswi[+]/Iswi² is a suppressor of wing vein | adult stage phenotype of Hsap\SMARCAL1^UAS.cBa, Scer\GAL4^Bx-MS1096

(Morimoto et al., 2016)

Iswi² is a suppressor of dorsocentral bristle phenotype of pnr^D1

(Vanolst et al., 2005)

Other

Statement

Reference

Acf¹, Iswi² has abdomen phenotype

(Fyodorov et al., 2004)

Acf¹, Iswi² has abdominal tergite 4 phenotype

(Fyodorov et al., 2004)

Acf¹, Iswi² has abdominal tergite 5 phenotype

(Fyodorov et al., 2004)

Acf¹, Iswi[+]/Iswi² has abdomen phenotype

(Fyodorov et al., 2004)

Acf¹, Iswi[+]/Iswi² has abdominal tergite 4 phenotype

(Fyodorov et al., 2004)

Acf¹, Iswi[+]/Iswi² has abdominal tergite 5 phenotype

(Fyodorov et al., 2004)

Iswi², msl-2^Hsp83.PK has X chromosome | female phenotype

(Corona et al., 2002)

Additional Comments

Genetic Interactions

Statement

Reference

The formation of ectopic wing veins observed in adult flies expressing Marcal1^Scer\UAS.cBa under the control of Scer\GAL4^tub.PU is ameliorated by combination with a single copy of Iswi².

(Morimoto et al., 2016)

One copy of Iswi² does not enhance the loss of His2Av⁸¹⁰ mutant germline stem cells (GSCs) in the testis. A similar proportion of testes contain His2Av⁸¹⁰ mutant GSC clones as with His2Av⁸¹⁰ alone.

(Morillo Prado et al., 2013)

Expression of Hsrω^{dsRNA.Sym.Scer\UAS} under the control of Scer\GAL4^ey.PH suppresses the defects seen in homozygous Iswi² eyes.

Expression of Hsrω^{dsRNA.Sym.Scer\UAS} under the control of Scer\GAL4^ey.PH suppresses the X chromosome condensation defects seen in the polytene chromosomes of Iswi¹/Iswi² male larvae.

(Onorati et al., 2011)

Acf1¹ and E(bx)^Nurf301-2 each enhance the eye defects seen in flies in which the eyes are homozygous for Iswi² in an otherwise heterozygous background (generated using the EGUF technique).

The defects seen in homozygous Iswi² eyes (generated using the EGUF technique) are dominantly suppressed by wun^PBacF48.

The defects seen in homozygous Iswi² eyes (generated using the EGUF technique) are dominantly suppressed by ttk^EP3314, mbf1^EP3684 or eff^EP3627 expressed under the control of Scer\GAL4^ey.PH.

casp^PBacG75α and wun^PBacF48 each suppress the shortening of the S phase, but not the G[[2]]/M increase which is seen in Iswi² larval brain neuroblast cell populations.

casp^PBacG75α and wun^PBacF48 each suppress the pre-G1 defects seen in Iswi² imaginal disc cell populations, restoring a cell cycle profile similar to wild type.

Expression of either eff^EP3627 or ttk^EP3314 under the control of Scer\GAL4^ey.PH weakly suppresses the pre-G[[1]] and G[[1]]-G[[2]]/M defects seen in Iswi² eye disc cell populations.

Expression of mbf1^EP3684 under the control of Scer\GAL4^ey.PH strongly suppresses the pre-G[[1]] and G[[1]]-G[[2]]/M defects seen in Iswi² eye disc cell populations.

(Arancio et al., 2010)

Iswi¹/Iswi²; Acf1[5]/+ animals have a significant developmental delay compared to Iswi¹/Iswi² single mutants, surviving to late third larval instar or early pupation.

(Liu et al., 2008)

Df(2R)ED3921 fails to suppress the melanotic tumour and increased larval hemocyte number of Iswi² mutants.

(Ragab, 2006)

The frequency of abnormal dorsal appendages in embryos derived from females carrying EcR^{B1-ΔC655.F645A.Scer\UAS} under the control of Scer\GAL4^slbo.2.6 (23%) is increased if the females are also heterozygous for Iswi² (45%).

(Badenhorst et al., 2005)

Iswi²/+ ; pnr^D1/+ flies display on average 2.84 dorsocentral bristles per heminotum, so reducing the number observed in pnr^D1/+ single mutants. Iswi²/+ ; pnr^VX1/+ flies display on average 1.61 dorsocentral bristles per heminotum, so aggravating the pnr^D1/+ single mutant phenotype (1.86 bristles/heminotum). Iswi²/+ ; Chi^E/+ flies display on average 1.29 dorsocentral bristles per heminotum, so accentuating the pnr^D1/+ single mutant phenotype (1.6 per heminotum).

(Vanolst et al., 2005)

When heterozygous Iswi¹ or Iswi² is combined with homozygous Acf1¹, animals exhibit a homeotic transformation in the abdomen of males. This phenotype is manifested as ectopic reduced pigmentation of the abdominal A5 tergites, consistent with an A4 to A5 transformation. The penetrance (in Acf1¹/Acf1¹, Iswi²/+ animals) is 26%. In addition mutant flies often display an aberrant, asymmetric segmentation of the lower abdomen.

(Fyodorov et al., 2004)

mle¹ completely suppresses the morphological defects of the X chromosome that are seen in salivary gland polytene chromosome preparations from Iswi² males.

Expression of msl-2^Hsp83.PK in a Iswi² background (but not in a wild-type background) results in the X chromosome having a bloated morphology in salivary gland polytene chromosome preparations from female larvae. In approximately 30% of the salivary gland nuclei, the phenotype is so severe that the X chromosome is almost completely dispersed and detaches from the chromocenter.

(Corona et al., 2002)

Xenogenetic Interactions

Statement

Reference

The formation of ectopic wing veins observed in adult flies expressing Hsap\SMARCAL1^Scer\UAS.cBa under the control of Scer\GAL4^Bx-MS1096 is ameliorated by combination with a single copy of Iswi².

(Morimoto et al., 2016)

Complementation and Rescue Data

Rescued by

Iswi² is rescued by Iswi^+t12

(Arancio et al., 2010)

Iswi²/Iswi¹ is rescued by Iswi^UAS.Tag:TAP

(Burgio et al., 2008)

Iswi² is rescued by Iswi^Tag:HA

(Xi and Xie, 2005)

Iswi² is rescued by Iswi^Tag:HA

(Deuring et al., 2000)

Iswi² is rescued by Iswi^+t12

(Deuring et al., 2000)

Not rescued by

Iswi² is not rescued by Iswi^K159R.Tag:HA

(Arancio et al., 2010)

Iswi² is not rescued by Iswi^tBR7

(Deuring et al., 2000)

Iswi² is not rescued by Iswi^K159R.Tag:HA

(Deuring et al., 2000)

Iswi² is not rescued by Iswi^tBR5

(Deuring et al., 2000)

Comments

The eye defects seen in flies in which the eyes are homozygous for Iswi² in an otherwise heterozygous background (generated using the EGUF technique) are fully rescued by Iswi^+t12.

The eye defects seen in flies in which the eyes are homozygous for Iswi² in an otherwise heterozygous background (generated using the EGUF technique) are not rescued by Iswi^{K159R.T:Ivir\HA1}.

(Arancio et al., 2010)

Expression of Iswi^{Scer\UAS.T:Zzzz\TAP} under the control of Scer\GAL4^Act5C.PU rescues the lethality of Iswi¹/Iswi² animals.

(Burgio et al., 2008)

Loss of Iswi² homozygous clones from their stem cell niche is supressed by Iswi^T:Ivir\HA1.

(Xi and Xie, 2005)

Images (0)

Mutant

Wild-type

Stocks (0)

Notes on Origin

Discoverer

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (3)

Reported As

Symbol Synonym

ISWI²

(Morillo Prado et al., 2013, Onorati et al., 2011, Sala et al., 2011, Arancio et al., 2010, Burgio et al., 2008, Sala et al., 2008, Corona et al., 2002)

Iswi²

(Kwon et al., 2021, Li et al., 2021, Morimoto et al., 2016, Mengoli et al., 2014, Kugler and Nagel, 2010, Siriaco et al., 2009, Corona et al., 2007)

iswi²

(Liu et al., 2008, Shcherbata et al., 2007, Xi and Xie, 2005)

Name Synonyms

Secondary FlyBase IDs

References (23)

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