FlyBase Allele Report: Dmel\piwi[1]

General Information

Symbol

Dmel\piwi¹

Species

D. melanogaster

Name

FlyBase ID

FBal0024637

Feature type

allele

Associated gene

Dmel\piwi

Associated Insertion(s)

P{PZ}piwi¹

Carried in Construct

Also Known As

piwi1

Key Links

Genomic Maps

JBrowse

Allele class

Mutagen

P-element activity

Nature of the Allele

Allele class

Mutagen

P-element activity

(Lin and Spradling, 1997)

Progenitor genotype

Associated Insertion(s)

P{PZ}piwi¹

Cytology

Description

P{PZ} is inserted in first exon. The orientation of the P{PZ} is opposite to that of the gene.

(Cox et al., 1998)

Allele components

Component

Use(s)

Inserted element

P{PZ}

enhancer trap

Encoded product / tool

lacZ

reporter enzyme

Tagged with

Tag:NLS(P)

nuclear protein localization tag

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

transposable_element_insertion_site

2L:10,987,117..10,987,453

(Lin et al., 2020, Handler et al., 2011, Poulton et al., 2011, Wang and Elgin, 2011, Smulders-Srinivasan et al., 2010, Li and Lu, 2009, Spradling et al., 1999, Cox et al., 1998, Lin and Spradling, 1997)

Variant Molecular Consequences

Associated Sequence Data

DDBJ / EMBL / GenBank

DNA sequence

Protein sequence

UniProtKB/Swiss-Prot

UniProtKB/TrEMBL

Expression Data

Reporter Expression

Additional Information

Statement

Reference

Marker for

Reflects expression of

Reporter construct used in assay

Human Disease Associations

Disease Ontology (DO) Annotations

Models Based on Experimental Evidence ( 0 )

Disease

Evidence

References

Modifiers Based on Experimental Evidence ( 1 )

Disease

Interaction

References

ameliorates brain cancer

modeled by l(3)mbt^ts1

(Janic et al., 2010)

exacerbates frontotemporal dementia and/or amyotrophic lateral sclerosis 7

modeled by Hsap\CHMP2B^{Intron5.13xlexAop}

(Fort-Aznar et al., 2020)

Comments on Models/Modifiers Based on Experimental Evidence ( 0 )

Disease-implicated variant(s)

Phenotypic Data

Phenotypic Class

abnormal mitotic cell cycle | germline clone

(Cox et al., 1998)

decreased fecundity | female | recessive

(Cox et al., 2000)

female sterile

(Lin and Spradling, 1997)

female sterile | recessive

(Cox et al., 2000, Spradling et al., 1999)

fertile (with piwi²), with piwi^nls.Tag:FLAG

(Chen et al., 2025)

fertile (with piwi^DUO.Tag:MYC)

(Darricarrère et al., 2013)

increased cell death (with piwi²)

(Zamparini et al., 2011)

lethal | non-rescuable maternal effect

(Cox et al., 1998)

male sterile

(Lin and Spradling, 1997)

male sterile | recessive

(Cox et al., 2000)

non-suppressor of variegation | dominant, with P{hsp26-pt-T}8-M76

(Wang et al., 2014)

non-suppressor of variegation | dominant, with P{hsp26-pt-T}39C-66

(Wang et al., 2014)

non-suppressor of variegation | dominant, with P{w⁺(-1360)}1250

(Wang et al., 2014)

non-suppressor of variegation | dominant, with P{w⁺(FRT.attP.1360)}1250

(Wang et al., 2014)

sterile (with piwi²), with piwi^{YK.nls.Tag:FLAG}

(Chen et al., 2025)

suppressor of variegation

(Pal-Bhadra et al., 2004)

suppressor of variegation, with P{T1(-FRT)}T190-177

(Haynes et al., 2006)

suppressor of variegation, with P{T1}T190-177

(Haynes et al., 2006)

viable (with piwi^DUO.Tag:MYC)

(Darricarrère et al., 2013)

Phenotype Manifest In

cephalopharyngeal skeleton | embryonic stage | maternal effect

(Rouget et al., 2010)

cystoblast | non-rescuable maternal effect

(Cox et al., 1998)

egg

(Cox et al., 2000)

embryo | embryonic stage 4 | germline clone | non-rescuable maternal effect

(Cox et al., 1998)

embryo | germline clone | non-rescuable maternal effect

(Cox et al., 1998)

embryonic/larval cuticle | embryonic stage | germline clone | maternal effect

(Rouget et al., 2010)

embryonic head | germline clone | non-rescuable maternal effect

(Cox et al., 1998)

female germline stem cell

(Lin and Spradling, 1997)

female germline stem cell | cell autonomous | somatic clone

(Cox et al., 2000)

female germline stem cell | non-rescuable maternal effect

(Cox et al., 1998)

germarium

(Szakmary et al., 2005)

germarium | non-rescuable maternal effect

(Cox et al., 1998)

germline cyst | non-rescuable maternal effect

(Cox et al., 1998)

male germline stem cell

(Lin and Spradling, 1997)

ovariole

(Szakmary et al., 2005)

ovariole (with piwi^EP1024)

(Szakmary et al., 2005)

ovariole | non-rescuable maternal effect

(Cox et al., 1998)

ovary (with piwi²)

(Chen et al., 2025, Ku et al., 2016, Zamparini et al., 2011)

ovary (with piwi^EP1024)

(Cox et al., 2000)

primordial germ cell | germline clone | maternal effect

(Megosh et al., 2006)

testis (with piwi^EP1024)

(Cox et al., 2000)

Detailed Description

Statement

Reference

piwi¹/piwi² mutants show defects in the ovaries.

(Ku et al., 2016)

piwi¹/piwi² ovaries show abnormal cell death.

(Zamparini et al., 2011)

Only 2% of embryos from piwi¹ germline clones are able to produce cuticle. Of those with cuticle 22/23 have head skeleton defects.

(Rouget et al., 2010)

Projection neuron morphogenesis is normal in mutant animals.

(Berdnik et al., 2008)

piwi¹ flies show a disruption of the heterochromatic silencing of the P{T1} reporter in line P{T1}T190-177 and of the P{T1(-FRT)} reporter in line P{T1(-FRT)}T190-177.

(Haynes et al., 2006)

Embryos produced by females with piwi¹ germline clones contain on average 7.5 pole cells at mitotic cycle 14, as compared to 24 pole cells in wild-type embryos at the same stage. 33% of the embryos from the piwi¹ clones have no pole cells at all.

(Megosh et al., 2006)

Ovarioles in mutant females typically contain a germlineless germarium and two to three egg chambers.

(Szakmary et al., 2005)

Suppressor of repeat-induced silencing, as seen at heterochromatic tandem arrays of insertions of the P{lacW} transposon.

(Pal-Bhadra et al., 2004)

Homozygous females do not lay eggs. The small number of eggs that they do produce are retained in the ovary and eventually atrophy. Homozygous germline stem cells (GSCs) (induced by mitotic recombination immediately prior to oogenesis) are present three weeks following oogenesis. The homozygous GSCs divide four-fold slower than their wild-type counterparts. Cysts and postgerminal egg chambers derived from these homozygous GSCs usually develop normally. piwi^EP1024/piwi¹ ovaries and testes show a typical piwi¹ mutant phenotype.

(Cox et al., 2000)

Female germ-line stem cells are of normal number but are mispositioned in third instar ovaries. Number of ovariole in most adult ovaries is within the normal range. Germ line stem cells differentiate without self-renewing divisions immediately following the initiation of oogenesis. Germ line stem cells and cystoblasts are undetectable in mutant ovaries, as indicated by the absence of spectrosome-containing germ cells. Most ovaries contain differentiated germ-line cysts whose number approximately equals that of the germ line stem cells. Cysts are much larger in size and contain two- to multicell stage fusomes, indicating their differentiated state. Adult ovaries contain only 2 normal or abnormal egg chambers connected to a germarium lacking other germ line cells. Embryos derived from germ-line clones are arrested in embryogenesis, and cannot be rescued by paternal piwi⁺. They have various defects, including mitotic defects during cleavage stage or later severe deformation of head region. Somatic clonal analysis reveals that piwi function is not required in follicle cells for egg chamber development.

(Cox et al., 1998)

Mutant males show severe defects in spermatogenesis. Mutant testes only contain 1-6 bundles of mature sperm but no other germline cells. Ovarioles are almost completely devoid of germline cells. Individual ovarioles are present but difficult to recognise. At low frequency some ovarioles contain a few developing egg chambers or mature eggs.

(Lin and Spradling, 1997)

male-sterile female-sterile ovaries rudimentary, degenerate

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Enhancer of

Statement

Reference

piwi[+]/piwi¹ is an enhancer of visible phenotype of Kr^If-1

(Gangaraju et al., 2011)

Suppressor of

Statement

Reference

piwi²/piwi¹ is a suppressor of male semi-fertile | progressive phenotype of Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰

(Ku et al., 2016)

piwi¹ is a suppressor | partially of neoplasia phenotype of l(3)mbt^ts1

(Janic et al., 2010)

piwi¹ is a suppressor of visible phenotype of E2f1^RNAi.C.UAS, Scer\GAL4^I-76-D

(Li and Lu, 2009)

NOT Suppressor of

Statement

Reference

piwi¹ is a non-suppressor of neoplasia phenotype of brat^k06028

(Janic et al., 2010)

piwi¹ is a non-suppressor of abnormal eye color phenotype of w^RNAi.GMR

(Pelisson et al., 2007)

Phenotype Manifest In

NOT Enhanced by

Statement

Reference

piwi¹ has germline stem cell phenotype, non-enhanceable by fs(1)Yb¹

(King et al., 2001)

Suppressed by

Statement

Reference

piwi²/piwi¹ has ovary phenotype, suppressible | partially by Ssrp^GFP.FPTB

(Chen et al., 2025)

piwi²/piwi¹ has ovary phenotype, suppressible | partially by Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰

(Ku et al., 2016)

NOT suppressed by

Statement

Reference

piwi¹ has germline stem cell phenotype, non-suppressible by fs(1)Yb¹

(King et al., 2001)

Enhancer of

Statement

Reference

piwi[+]/piwi¹ is an enhancer of eye phenotype of Kr^If-1

(Gangaraju et al., 2011)

NOT Enhancer of

Statement

Reference

piwi¹ is a non-enhancer of germline stem cell phenotype of fs(1)Yb¹

(King et al., 2001)

Suppressor of

Statement

Reference

piwi²/piwi¹ is a suppressor | partially of testis phenotype of Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰

(Ku et al., 2016)

piwi[+]/piwi¹ is a suppressor | partially of testis phenotype of Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰

(Ku et al., 2016)

piwi¹ is a suppressor of eye phenotype of E2f1^RNAi.C.UAS, Scer\GAL4^I-76-D

(Li and Lu, 2009)

piwi¹ is a suppressor of antenna phenotype of E2f1^RNAi.C.UAS, Scer\GAL4^I-76-D

(Li and Lu, 2009)

piwi¹ is a suppressor of wing phenotype of sd^Fab-X

(Grimaud et al., 2006)

NOT Suppressor of

Statement

Reference

piwi¹/piwi¹ is a non-suppressor of eye phenotype of w^RNAi.GMR

(Pelisson et al., 2007)

piwi¹ is a non-suppressor of germline stem cell phenotype of fs(1)Yb¹

(King et al., 2001)

Additional Comments

Genetic Interactions

Statement

Reference

piwi¹/+ (or even more so, piwi¹/piwi²) significantly partially suppresses the swollen apical tip of the testis phenotype seen in Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰ males. piwi¹/piwi² suppresses infertility seen in Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰ males. Tudor-SN⁰⁶¹⁴/Tudor-SN¹¹²⁰ partially suppresses ovary defects in piwi¹/piwi² females.

(Ku et al., 2016)

piwi¹/+ enhances the eye outgrowth phenotype phenotype of Kr^If-1; approximately 7% of the progeny have an eye outgrowth phenotype in a cross of piwi¹/+ females to Kr^If-1/+ males. However, the reciprocal cross of Kr^If-1/+ females to piwi¹/+ males does not result in progeny with an eye outgrowth phenotype, indicating a maternal effect.

(Gangaraju et al., 2011)

The frequency with which l(3)mbt^ts1 larval brain tissue develops into tumours after allograft into adult host flies (taking over the entire abdomen of the host) is markedly reduced if the transplanted tissue is also homozygous for piwi¹.

The frequency with which brat^k06028 larval brain tissue develops into tumours after allograft into adult host flies (taking over the entire abdomen of the host) is not significantly altered if the transplanted tissue is also homozygous for piwi¹.

(Janic et al., 2010)

piwi¹ suppresses the eye and antenna traits of flies expressing E2f^{dsRNA.C.Scer\UAS} under the control of Scer\GAL4^I-76-D.

(Li and Lu, 2009)

The yellowish eye colour caused by expression of one copy of w^dsRNA.GMR in a wild-type background is not altered if the flies are also homozygous for piwi¹.

(Pelisson et al., 2007)

piwi¹/+ does not impair cytotype-mediated repression of P-element excision.

(Simmons et al., 2007)

The wing phenotype of sd^Fab-X flies is suppressed in sd^Fab-X;piwi¹ flies.

(Grimaud et al., 2006)

piwi¹ ; bam^Δ86 double mutant ovarioles have mildly tumorous germaria filled with 50-300 undifferentiated germ cells with no apparent egg chamber development.

(Szakmary et al., 2005)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Rescued by

piwi²/piwi¹ is rescued by piwi^nls.Tag:FLAG

(Chen et al., 2025)

piwi¹ is rescued by piwi^DUO.Tag:MYC

(Darricarrère et al., 2013)

piwi¹ is rescued by piwi^{bcd.3'UTR.Tag:MYC}

(Megosh et al., 2006)

piwi^EP1024/piwi¹ is rescued by Scer\GAL4^hs.PB, piwi^EP1024

(Cox et al., 2000)

piwi¹ is rescued by piwi^+t6.8

(Cox et al., 1998)

Partially rescued by

piwi²/piwi¹ is partially rescued by piwi^{YK.nls.Tag:FLAG}

(Chen et al., 2025)

Not rescued by

piwi²/piwi¹ is not rescued by piwi^YK.GFP

(Le Thomas et al., 2013)

piwi¹ is not rescued by piwi^3'Tag:MYC

(Cox et al., 2000)

piwi¹ is not rescued by piwi^RLD

(Cox et al., 1998)

Comments

Expression of two copies of piwi^{DUO.T:Hsap\MYC} rescues the ovary phenotypes and egg laying defects seen in homozygous piwi¹ mutant flies.

Expression of two copies of piwi^5'T:Hsap\MYC rescues the ovary phenotypes and egg laying defects seen in homozygous piwi¹ mutant flies.

(Darricarrère et al., 2013)

When piwi^EP1024 is overexpressed under the control of Scer\GAL4^hs.PB using heat shock treatment (1 hour at 37^oC every day starting from the larval stage) in a piwi^EP1024/piwi¹ background, significant rescue of the piwi^EP1024/piwi¹ mutant phenotype is seen in both females and males. Specifically, in females, germline stem cells are maintained and a string of developing egg chambers are observed, while in males, germline stem cells are also rescued and spermatogenesis is fully restored. Fertility is rescued to wild-type levels. Heat shock starting at the pupal stage does not rescue fertility.

(Cox et al., 2000)

Embryos derived from germ-line clones are arrested in embryogenesis, and cannot be rescued by paternal piwi⁺.

(Cox et al., 1998)

Images (0)

Mutant

Wild-type

Stocks (1)

Bloomington

43637

w¹¹¹⁸; P{PZ}piwi¹/CyO, P{ActGFP}JMR1

Notes on Origin

Discoverer

Comments

Mobilisation of the P{PZ} insertion reverts the mutant phenotype.

(Lin and Spradling, 1997)

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (3)

Reported As

Symbol Synonym

fs(2)P-1

(Beaton, 1999.12.12, Spradling et al., 1999)

piwi1

(Le Thomas et al., 2013, Brennecke et al., 2007)

piwi¹

(Chavan et al., 2025, Chen et al., 2025, Lim et al., 2022, Fort-Aznar et al., 2020, Lin et al., 2020, Stein et al., 2019, Wakisaka et al., 2019, Teixeira et al., 2017, Klein et al., 2016, Ku et al., 2016, Basquin et al., 2014, Minakhina et al., 2014, Wang et al., 2014, Darricarrère et al., 2013, Dönertas et al., 2013, Jin et al., 2013, Li et al., 2013, Sienski et al., 2012, Simmons et al., 2012, Gangaraju et al., 2011, Handler et al., 2011, Poulton et al., 2011, Zamparini et al., 2011, Janic et al., 2010, Olivieri et al., 2010, Rouget et al., 2010, Simmons et al., 2010, Smulders-Srinivasan et al., 2010, Habayeb et al., 2009, Li and Lu, 2009, Berdnik et al., 2008, Josse et al., 2007, Pelisson et al., 2007, Simmons et al., 2007, Yin and Lin, 2007, Grimaud et al., 2006, Haynes et al., 2006, Megosh et al., 2006, Megosh et al., 2006)

Name Synonyms

Secondary FlyBase IDs

References (52)

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