FlyBase Allele Report: Dmel\Incenp[QA26]

General Information

Symbol

Dmel\Incenp^QA26

Species

D. melanogaster

Name

FlyBase ID

FBal0012084

Feature type

allele

Associated gene

Dmel\Incenp

Associated Insertion(s)

Carried in Construct

Key Links

Genomic Maps

JBrowse

Allele class

Mutagen

ethyl methanesulfonate

Nature of the Allele

Allele class

Mutagen

ethyl methanesulfonate

(Schupbach and Wieschaus, 1989)

Progenitor genotype

Cytology

Description

Point mutation which alters a conserved residue within the IN box.

(Colombié et al., 2008)

Amino acid replacement: D675V.

(Resnick et al., 2006)

Mutations Mapped to the Genome

Curation Data

Type

Location

Additional Notes

References

point_mutation

2R:7,281,087..7,281,087 [+]

Nucleotide change:

A7281087T

Amino acid change:

D675V | Incenp-PA; D675V | Incenp-PB; D674V | Incenp-PC

Reported amino acid change:

D675V

Comment:

Site of nucleotide substitution in mutant inferred by FlyBase based on reported amino acid change.

(Resnick et al., 2006)

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 ( 0 )

Disease

Interaction

References

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

Disease-implicated variant(s)

Phenotypic Data

Phenotypic Class

abnormal meiotic cell cycle | oogenesis

(Radford et al., 2012)

female sterile | recessive

(Schupbach and Wieschaus, 1989)

lethal - all die during embryonic stage | non-rescuable maternal effect | recessive

(Schupbach and Wieschaus, 1989)

male semi-sterile

(Resnick et al., 2006)

some die during embryonic stage | recessive

(Schupbach and Wieschaus, 1989)

viable

(Resnick et al., 2006)

Phenotype Manifest In

chromosome & meiotic primary spermatocyte

(Resnick et al., 2006)

chromosome & meiotic secondary spermatocyte

(Resnick et al., 2006)

oocyte

(Radford et al., 2012)

oocyte | oogenesis stage S12

(Resnick et al., 2009)

oocyte | oogenesis stage S13

(Resnick et al., 2009)

spindle midzone & oocyte

(Colombié et al., 2008)

spindle pole & oocyte

(Colombié et al., 2008)

Detailed Description

Statement

Reference

Incenp^QA26 oocytes exhibit only one focus for each pair of centromeres and mono-orientation of homologous chromosomes while they exhibit chromosome movements and bipolar spindles (in majority) as compared to controls.

(Radford et al., 2012)

55% of stage 12 and 13 oocytes show prometaphase I configurations with separated chromosomes in homozygous females, but by stage 14, the oocytes have configurations comparable to those seen in wild-type control oocytes.

Embryos derived from Incenp^QA26 females arrest early, with defects such as chromosome bridging in the first anaphase.

The condensed chromosomes normally present in the polar body rosette structure of early embryos have aberrant morphology in embryos derived from Incenp^QA26 females; the chromosomes are elongated and fragmented.

(Resnick et al., 2009)

The morphology of the metaphase-I arrested spindle in female meiosis is disrupted in over 50% of oocytes in Incenp^QA26 females. Typical defects include the formation of one or more ectopic spindle poles, usually around the equator or next to the main poles. Chromosome alignment or location is abnormal in 32% of mutant metaphase-I arrested oocytes, compared to 15% of control oocytes.

Live-imaging analysis of metaphase I-arrested spindles in Incenp^QA26 oocytes indicates that approximately 40% have an abnormal morphology, typically ectopic or split poles, at the beginning of the observation. Half of these abnormal spindles become bipolar during the observation (typically 20-40 minutes), whereas some of the others change their morphology but remain abnormal. Conversely, most of the initially bipolar spindles remain bipolar during the observation, but some lose their bipolarity, mostly through the appearance of ectopic poles, or, less often, splitting of poles. Ectopic poles usually grow from the spindle equatorial region, and spindle bipolarity is restored by disassembling the ectopic pole or merging it with one of the main poles. In total, more than one-third of the observed spindles show at least one interconversion between bipolar and abnormal morphology during the period of observation.

Spindle microtubules are assembled around the chromosomes after nuclear envelope breakdown in the mutant oocytes and multiple transitory poles appear at the beginning of spindle formation, as occurs in wild type. However, unlike in wild type, even after one spindle axis has become dominant, other poles continue to be formed in the mutant oocytes. In addition, the time between nuclear envelope breakdown and the first appearance of microtubules around the chromosomes is significantly increased in the mutant oocytes compared to wild type.

The spindle equatorial region is defective in the mutant oocytes, having a significantly reduced tubulin intensity at the midzone relative to the poles compared to wild-type oocytes.

The length of the metaphase I spindle in mutant oocytes is not significantly different from that of wild type.

(Colombié et al., 2008)

Homozygous female complete meiosis without detectable defects, but there are defects in embryonic mitoses.

Homozygous males have reduced fertility.

Mutant males show defects in meiosis I; small bits of chromatin that could result from chromosome fragmentation or aberrant condensation are seen.

Homozygous males show increased nondisjunction of the sex chromosomes during meiosis (15.8%) compared to controls (0.6%).

Mutant spermatocytes show defective chromosome condensation in meiosis; prophase I figures with loosely packed and minimally condensed chromosomes are seen in 34% of mutant spermatocytes compared to 14% of wild-type spermatocytes. The mutant spermatocytes also show premature loss of sister chromatid cohesion in prometaphase I; bivalents that are compacted into blobs but have protruding arms that appear to be single sister chromatids are seen. Anaphase I spermatocytes contain completely separated sister chromatids at the poles and prometaphase II cells with separated sister chromatids are also seen. Precocious sister chromatid separation is seen in 34% of mutant spermatocytes in which the chromosome arrangement allows cohesion to be assessed. Aneuploid meiosis II spermatocytes are also seen.

(Resnick et al., 2006)

Eggs derived from homozygous females show no visible sign of embryonic development when observed under transmitted light in a stereo microscope. After 4-6 hours after egg deposition the originally unformly dense (like wild type) yolk mass starts to disintegrate into a network of darker and lighter yolk droplets. The defect may be in fertilisation or very early in embryonic development.

(Schupbach and Wieschaus, 1989)

External Data

Linkouts

Interactions

Show genetic interaction network for Enhancers & Suppressors

Phenotypic Class

Suppressor of

Statement

Reference

Incenp[+]/Incenp^QA26 is a suppressor | partially of abnormal cell cycle phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Phenotype Manifest In

Enhanced by

Statement

Reference

Incenp^QA26 has oocyte | oogenesis stage S12 phenotype, enhanceable by ord[+]/ord¹⁰

(Resnick et al., 2009)

Incenp^QA26 has oocyte | oogenesis stage S13 phenotype, enhanceable by ord[+]/ord¹⁰

(Resnick et al., 2009)

Suppressor of

Statement

Reference

Incenp[+]/Incenp^QA26 is a suppressor | partially of egg chamber phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Incenp[+]/Incenp^QA26 is a suppressor | partially of ring canal phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Incenp[+]/Incenp^QA26 is a suppressor | partially of nurse cell phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Incenp[+]/Incenp^QA26 is a suppressor | partially of oocyte phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Incenp[+]/Incenp^QA26 is a suppressor | partially of female germline cyst phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Incenp[+]/Incenp^QA26 is a suppressor | partially of female fusome phenotype of Det^{S125E.UASp.GFP}, Scer\GAL4^{VP16.nanos.UTR}

(Mathieu et al., 2013)

Other

Statement

Reference

Df(2L)Exel7049/+, Incenp^QA26 has synaptonemal complex phenotype

(Resnick et al., 2009)

Df(2L)Exel7049/+, Incenp^QA26 has oocyte | oogenesis stage S12 phenotype

(Resnick et al., 2009)

Df(2L)Exel7049/+, Incenp^QA26 has oocyte | oogenesis stage S13 phenotype

(Resnick et al., 2009)

Incenp^QA26, ord[+]/ord¹⁰ has synaptonemal complex phenotype

(Resnick et al., 2009)

Incenp^QA26, ord[+]/ord¹⁰ has oocyte | oogenesis stage S14 phenotype

(Resnick et al., 2009)

Additional Comments

Genetic Interactions

Statement

Reference

A Incenp^QA26/+ background partially rescues the extra germline cells phenotype found in females expressing Det^{S125E.Scer\UAS.P\T.T:Avic\GFP} under the control of Scer\GAL4^{nos.UTR.T:Hsim\VP16}.

(Mathieu et al., 2013)

Assembly of the synaptonemal complex is unaffected in the ovaries of Incenp^QA26 Df(2L)Exel7049/Incenp^QA26 females. However, these females show premature disassembly of the synaptonemal complex.

69% of stage 12 and 13 oocytes show prometaphase I configurations with separated chromosomes in Incenp^QA26 Df(2L)Exel7049/Incenp^QA26 females, but by stage 14, only 17% of oocytes have aberrant metaphase I chromosome configurations.

Premature sister chromatid separation is not seen in metaphase I oocytes from Incenp^QA26 Df(2L)Exel7049/Incenp^QA26 females. However, the X chromosomes often fail to biorient and are oriented towards the same pole (80% of cases). The fourth chromosomes are most often bioriented, but sometimes they are also monooriented.

Assembly of the synaptonemal complex is normal in the ovaries of Incenp^QA26 ord¹⁰/Incenp^QA26 females. However, these females show premature disassembly of the synaptonemal complex.

85% of stage 12 and 13 oocytes show prometaphase I configurations with separated chromosomes in Incenp^QA26 ord¹⁰/Incenp^QA26 females, and at stage 14, 53% of the oocytes have aberrant metaphase I chromosome configurations. The X and fourth chromosomes show a failure of bivalent biorientation.

(Resnick et al., 2009)

Xenogenetic Interactions

Statement

Reference

Complementation and Rescue Data

Fails to complement

Incenp^EC3747

(Colombié et al., 2008)

Comments

Images (0)

Mutant

Wild-type

Stocks (1)

Bloomington

5032

cn¹ Incenp^QA26 bw¹/CyO, l(2)DTS513¹

Notes on Origin

Discoverer

External Crossreferences and Linkouts ( 0 )

Synonyms and Secondary IDs (6)

Reported As

Symbol Synonym

Incenp^QA26

(Hasan et al., 2024, Das et al., 2016, Radford et al., 2012)

QA26

(Resnick et al., 2006)

incenp^QA26

(Mathieu et al., 2013, Resnick et al., 2009, Colombié et al., 2008)

mat(2)ea-C¹

mat(2)eaQA26

mat(2)earlyQA26

(Schupbach and Wieschaus, 1989)

Name Synonyms

Secondary FlyBase IDs

References (8)

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