FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Allele: Dmel\Larbola2
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General Information
Symbol
Dmel\Larbola2
Species
D. melanogaster
Name
bola2
FlyBase ID
FBal0095666
Feature type
allele
Associated gene
Associated Insertion(s)
Carried in Construct
Key Links
Allele class
Nature of the Allele
Allele class
Progenitor genotype
Associated Insertion(s)
Cytology
Description

Insertion in the first intron of Lar, 5.4 kb downstream of the 3' end of exon 1.

Allele components
Component
Use(s)
Inserted element
Encoded product / tool
Mutations Mapped to the Genome
Curation Data
Type
Location
Additional Notes
References
Variant Molecular Consequences
Associated Sequence Data
DNA sequence
Protein sequence
 
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
Phenotype Manifest In
Detailed Description
Statement
Reference

Larbola1/Larbola2 transheterozygous eggs are rounder than controls (Larbola1/+, Larbola2/+ and wild-type). Follicular epithelium stress fibers are highly misaligned in stage 5 egg chambers, but become less misaligned at stage 7, as compared to wild-type and Larbola2 heterozygous controls.

In Larbola2 heterozygotes, follicular epithelium migration is severely increased in stage 7 egg chambers, as compared to controls.

Larbola1/Larbola2 follicular epithelia show a fully penetrant yet variable defect in their migration motility, as compared to controls, with around half of these mutant epithelia exhibiting no migration, while the rest migrate slower than controls.

In mutant females 20-70% of the follicles fail to elongate, despite transferring their nurse cell contents normally. Unelongated follicles develop into eggs that are nearly round, resembling a football (sensu UK) and contain unelongated follicle cells, but enclose a normal volume. Stage 10A bola follicles reveal normal actin microfilament bundles in their nurse cells. Their basal actin filaments are indistinguishable from wild-type in the germarium and stage 2-4 egg chambers. However in 30-90% of follicles, the filaments, the filaments never become aligned perpendicular to the anterior posterior axis, although intracellularly, the number and size of actin bundles appear normal. Nearly half of mutant follicles contain an average of 2.3 anterior polar cells and 2.6 posterior polar cells (compared to two pairs in wild-type). Moreover 3.3% of the follicles contain an ectopic polar cell cluster from 2-12 cells. All the follicles with extra pole cells, whether located at the poles or ectopically, fail to undergo actin alignment. However the converse is not true. Many follicles are observed in which the number and location of polar cells is normal, but the actin fibres are not aligned. Germaria from mutant females are frequently found top be abnormal. In 57% of these germaria the cysts in region 2b remain two-across and never become lens shaped. Egg chamber budding is slowed and occurs abnormally, frequently causing additional round cysts to accumulate in region 3 of the germarium, and occasionally producing composite follicles containing two cysts. Although mutants oocytes never initiate embryonic development, anterior posterior polarity is seen do be disrupted (as seen by osk localisation).

Mutants produce round eggs. The organisation of the cytoskeleton within the follicle cells is disrupted; the actin bundles are still aligned within each cell, but these bundles are not always perpendicular to the anterior/posterior axis, as seen in wild type.

External Data
Interactions
Show genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Enhancer of
Statement
Reference
Suppressor of
Statement
Reference

Larbola2/Lar[+] is a suppressor of abnormal size | oogenesis phenotype of Sema5cK175

Larbola2/Lar[+] is a suppressor of visible | oogenesis phenotype of Sema5cK175

NOT Suppressor of
Statement
Reference

Larbola2/Lar[+] is a non-suppressor of abnormal cell migration | oogenesis phenotype of Sema5cK175

Phenotype Manifest In
Enhancer of
Statement
Reference

Larbola2/Lar[+] is an enhancer of egg phenotype of PlexAHM05221, Scer\GAL4NP1624

Suppressor of
Statement
Reference

Larbola2/Lar[+] is a suppressor | partially of follicle cell phenotype of Sema5cK175

Larbola2/Lar[+] is a suppressor of egg phenotype of Sema5cK175

Larbola2/Lar[+] is a suppressor | partially of stress fiber | oogenesis phenotype of Sema5cK175

NOT Suppressor of
Statement
Reference

Larbola2/Lar[+] is a non-suppressor | partially of follicle cell phenotype of Sema5cK175

Additional Comments
Genetic Interactions
Statement
Reference
Xenogenetic Interactions
Statement
Reference
Complementation and Rescue Data
Comments
Images (0)
Mutant
Wild-type
Stocks (1)
Notes on Origin
Discoverer
Comments
Comments

Etymology: 'bola' is Portuguese for ball, after the ball-like eggs laid by mutants.

External Crossreferences and Linkouts ( 0 )
Synonyms and Secondary IDs (4)
Reported As
Name Synonyms
Secondary FlyBase IDs
    References (4)