FB2024_03 , released June 25, 2024
Allele: Dmel\sn3
Open Close
General Information
Symbol
Dmel\sn3
Species
D. melanogaster
Name
FlyBase ID
FBal0015773
Feature type
allele
Associated gene
Dmel\sn
Associated Insertion(s)
Carried in Construct
Also Known As
singed3
Key Links
Allele class
Mutagen
Nature of the Allele
Allele class
Mutagen
spontaneous
(Cant et al., 1994, Roiha et al., 1988)
Progenitor genotype
Cytology
Description

0.3kb deletion from 1184bp to 1475bp of the wild-type sequence. This deletion is in the 5' end of the gene, and the coding region is intact.

(Paterson and O'Hare, 1991)
Mutations Mapped to the Genome
Curation Data
Type
Location
Additional Notes
References
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
      Phenotype Manifest In
      Detailed Description
      Statement
      Reference

      The number and density of spiked protrusions on the dendrites of class III ldaB neurons is reduced in mutant third instar larvae compared to wild type, while the total branch length of the dendritic tree is normal. The fraction of spiked protrusions that exceed 10 μm in length is increased in the mutant larvae.

      (Nagel et al., 2012)

      Sensory bristles are gnarled and wavy in sn3 adults.

      (Zanet et al., 2009)

      sn3 mutants exhibit a normal looking ellipsoid body.

      (Ilius et al., 2007)

      The cuticles of sn3 mutants show thin, crooked, abnormal denticles.

      (Chanut-Delalande et al., 2006)

      Neurons cultured from sn3/sn3 brains have a distinctive abnormal morphology. Axons curl, creating a filagree pattern. Filamentous axon distribution within these neurons is abnormal.

      (Kraft et al., 2006)

      The wing hairs of sn3 mutants show a 12-14% reduction in length compared to wild-type hairs. Few actin bundles are present in transverse or longitudinal sections taken through sn3 hairs; rather, the actin filaments are present in an almost diffuse cortical layer.

      (Guild et al., 2005)

      The bristles of sn3 mutants are twisted; bristles can twist either to the right, to the left, or first in one direction and then the other. These mutant bristles have large gaps between flutes, reflecting abnormal distribution of the actin bundles. Apart from where twisting occurs, the curvature of sn3 bristles is similar to wild type. Additionally, sn3 mutant bristles lie flat over the surface of the thorax, instead of pointing away from the thorax, as in wild type.

      (Tilney et al., 2004)

      sn3 adults exhibit bent and twisted bristles of normal length. This phenotype is more pronounced in macrochaetes than microchaetes. Each macrochaete flute is not equally spaced nor equal in size and is twisted. Particularly in the lower half of the bristle, a honeycomb of short ridges 5-10υm in length is found, most of which is connected to a major longitudinal ridge. Overall, the ridges and valleys have a collective longitudinal orientation and continuous ridges of over 50υm in length and are common on most bristles, especially near the tip.

      (Guild et al., 2003)

      The longitudinal actin bundles of wild-type bristle cells are composed of a hexagonally-packed array of actin filaments that form a triangular shape at the plasma membrane. sn3 mutants lack the fascin cross-bridges that usually form between actin filaments within a bundle. The longitudinal bundles of sn3 bristle cells contain fewer filaments than wild type; these filaments are liquid ordered not hexagonally-packed. These defects cause the bundles to form a rectangular shape that does not extend as far into the cytoplasm as the wild-type triangular bundle.

      (Tilney et al., 2003)

      The arista laterals are shorter than normal and weakly curved in mutant flies.

      (He and Adler, 2002)

      Actin bundles in the bristles of heterozygous flies are comparable in number and size to wild type and the area occupied by the filaments is not significantly different from wild type. The filaments are hexagonally packed. The bristles are the same length as in wild-type flies. Bristles of homozygotes are shorter than wild type.

      (Tilney et al., 2000)

      Strong bristle phenotype.

      (O'Hare et al., 1998)

      Mutation causes a severe denticle phenotype. Denticles tend to be smaller and have thinner hooks than wild-type denticles. They are also less orderly along each row and sometimes have a floppy appearance.

      (Dickinson and Thatcher, 1997)

      Actin bundles are twisted in sn3 bristles.

      (Tilney et al., 1996)

      Macrochaetae are bent, gnarled, twisted and considerably shorter than in wild-type flies. Microchaetae are often irregularly bent, and are shorter and less rigid than in wild-type flies. The ridges and valleys on the surface of the microchaetae are distorted. Actin bundles within the bristle cells are smaller and flatter than normal, and the filaments within them are disordered.

      (Tilney et al., 1995)

      Bristles are gnarled due to disrupted actin filament bundles.

      (Cant et al., 1994)

      Extreme bristle phenotype.

      (Paterson and O'Hare, 1991)

      Extreme bristle phenotype, female fertile.

      (Roiha et al., 1988)

      sn68/sn3 females have a sn mutant phenotype and are fertile.

      (Kaufman, 1969)

      class 3 - female fertile with gnarled macrochaetae and kinky microchaetae

      External Data
      Interactions
      Show genetic interaction network for Enhancers & Suppressors
      Phenotypic Class
      NOT Enhancer of
      Statement
      Reference

      sn3 is a non-enhancer of abnormal optomotor response phenotype of ebo678

      (Ilius et al., 2007)
      NOT Suppressor of
      Statement
      Reference

      sn3 is a non-suppressor of abnormal optomotor response phenotype of ebo678

      (Ilius et al., 2007)
      Other
      Statement
      Reference

      f36a, sn3 has visible phenotype

      (Fei et al., 2002)
      Phenotype Manifest In
      Enhanced by
      Statement
      Reference

      m1, sn3 has denticle phenotype, enhanceable by f36a

      (Chanut-Delalande et al., 2006)

      f36a, m1, sn3 has denticle phenotype, enhanceable by shaV15

      (Chanut-Delalande et al., 2006)

      f36a, m1, sn3 has larval abdominal dorsal trichome phenotype, enhanceable by shaV15

      (Chanut-Delalande et al., 2006)

      f36a, m1, sn3 has denticle phenotype, enhanceable by WASp3

      (Chanut-Delalande et al., 2006)

      f36a, m1, sn3 has larval abdominal dorsal trichome phenotype, enhanceable by WASp3

      (Chanut-Delalande et al., 2006)

      sn3 has denticle phenotype, enhanceable by m1

      (Chanut-Delalande et al., 2006)

      sn3 has microchaeta phenotype, enhanceable by f36a

      (Tilney et al., 2004)

      sn3 has macrochaeta phenotype, enhanceable by f36a

      (Guild et al., 2003)

      sn3 has microchaeta & actin filament phenotype, enhanceable by f36a

      (Tilney et al., 2003)
      NOT Enhanced by
      Statement
      Reference

      sn3 has arista phenotype, non-enhanceable by f36a

      (He and Adler, 2002)
      NOT suppressed by
      Statement
      Reference

      sn3 has arista phenotype, non-suppressible by f36a

      (He and Adler, 2002)

      sn3 has phenotype, non-suppressible by su(Hw)2

      (Lindsley and Grell, 1968)
      Enhancer of
      Statement
      Reference

      sn3 is an enhancer of denticle phenotype of f36a, m1

      (Chanut-Delalande et al., 2006)

      sn3 is an enhancer of denticle phenotype of m1

      (Chanut-Delalande et al., 2006)

      sn3 is an enhancer of microchaeta phenotype of f36a

      (Tilney et al., 2004)

      sn3 is an enhancer of macrochaeta phenotype of f36a

      (Guild et al., 2003)

      sn3 is an enhancer of microchaeta & actin filament phenotype of f36a

      (Tilney et al., 2003)
      NOT Enhancer of
      Statement
      Reference

      sn[+]/sn3 is a non-enhancer of scutellar bristle phenotype of IKKεDN.UAS, Scer\GAL4sca.PU

      (Otani et al., 2011)

      sn3 is a non-enhancer of ellipsoid body phenotype of ebo678

      (Ilius et al., 2007)

      sn3 is a non-enhancer of fan-shaped body phenotype of ebo678

      (Ilius et al., 2007)

      sn3 is a non-enhancer of arista phenotype of f36a

      (He and Adler, 2002)
      NOT Suppressor of
      Statement
      Reference

      sn[+]/sn3 is a non-suppressor of scutellar bristle phenotype of IKKεDN.UAS, Scer\GAL4sca.PU

      (Otani et al., 2011)

      sn3 is a non-suppressor of ellipsoid body phenotype of ebo678

      (Ilius et al., 2007)

      sn3 is a non-suppressor of fan-shaped body phenotype of ebo678

      (Ilius et al., 2007)

      sn3 is a non-suppressor of arista phenotype of f36a

      (He and Adler, 2002)
      Other
      Additional Comments
      Genetic Interactions
      Statement
      Reference

      In f36a sn3 double homozygous embryos, tracheal actin rings are formed properly similar to controls.

      (Öztürk-Çolak et al., 2016)

      ebo678 sn3 double mutants exhibit differences in the appearance of the ellipsoid and fan-shaped bodies, compared to wild-type and exhibit behavioral defects as found in ebo678 single mutants. The ellipsoid body defect is clearly visible in 100% of the animals but is more variable, ranging from just open at the bottom, to totally dissociated into two lumps of neuropil.

      No correlation is observed between the severity of the structural and behavioral defects in ebo678 sn3 gynandromorphs. Of those gynandromorphs in which the central complex can be distinguished, roughly half exhibit abnormal ellipsoid bodies and behavioral defects. Mutant yaw torque activity and torque spike frequency is found in about 39% and 64% of ebo678 sn3 gynandromorphs.

      (Ilius et al., 2007)

      The denticles of m1, sn3 mutants show splitting in addition to the defects seen in either single mutant. sn3, m1, f36a triple mutants have small, highly misshapen denticles that are more affected than those of m1, f36a or m1, sn3 double mutants. sn3, m1, f36a; shaV15 and sn3, m1, f36a; WASp3 quadruple mutants show further impairment to denticle formation compared to sn3, m1, f36a triple mutants, with mutants exhibiting regions of naked cuticle where denticles lie in wild-type animals.

      The dorsal hairs on the abdominal segments of sn3, m1, f36a triple mutants are severly reduced in size, and in some cases, hairs are abrogated leaving abnormal naked regions. This phenotype is more severe in sn3, m1, f36a; WASp3 quadruple mutants and is even more severe in sn3, m1, f36a; shaV15 mutants in which most dorsal hairs are absent, leaving naked cuticle.

      (Chanut-Delalande et al., 2006)

      sn3, f36a double mutants have bristles that are short, like f36a mutants, and twisted, like sn3 mutants.

      (Tilney et al., 2004)

      In f36a sn3 double mutants, bristle ridges of length more than 10υm (45% of wild-type length) are not found. Instead, a variety of short ridges 3-10υm in length are found. Some of these are parallel to the longitudinal axis of the bristle, whereas others are perpendicular or oblique. These ridges are seldom connected to one another but terminate freely on the surface.

      (Guild et al., 2003)

      In f36a, sn3 double mutants, bristle cells contain tiny rafts of membrane-attached actin filament clusters, which consist of a monolayer of filament. This is a more extreme phenotype than that observed with either of the single mutants. When these f36a, sn3 mutant cells are treated with jasplakinolide, large clusters of actin filaments appear internally, most of which run parallel to the longitudinal axis of the bristle. These clusters have an irregular shape and have a liquid ordered packing of filaments, instead of wild-type hexagonal packing.

      (Tilney et al., 2003)

      sn3 f36a double mutants have ocellar bristles which are shorter and have a smaller volume than normal.

      (Fei et al., 2002)

      The arista lateral phenotype of sn3 f36a double mutants is not substantially stronger than either single mutant. Double mutant arista laterals are thinner than wild type. At a low frequency, branched laterals are seen. The mutant laterals start to extend at the normal time, but their rate of extension is slower than normal.

      (He and Adler, 2002)

      Only 2% of postvertical bristles are split in sn3 f36a flies. The frequency of split bristles is increased by injection of cytochalasin D. Bristle elongation in sn3 f36a flies is more sensitive to vinblastine than in wild-type flies.

      (Geng et al., 2000)
      Xenogenetic Interactions
      Statement
      Reference
      Complementation and Rescue Data
      Rescued by

      sn3 is rescued by snUASp.EGFP/Scer\GAL4hs.PB

      (Zanet et al., 2009)

      sn3 is rescued by snS52A.UASp.EGFP/Scer\GAL4hs.PB

      (Zanet et al., 2009)
      Not rescued by

      sn3 is not rescued by snS52E.UASp.EGFP/Scer\GAL4hs.PB

      (Zanet et al., 2009)
      Comments

      Scer\GAL4hs.PB-driven expression of snScer\UAS.P\T.T:Avic\GFP-EGFP fully rescues the gnarled bristle phenotype exhibited by sn3 mutants.

      Scer\GAL4hs.PB-driven expression of snS52A.Scer\UAS.P\T.T:Avic\GFP-EGFP fully rescues the gnarled bristle phenotype exhibited by sn3 mutants.

      Scer\GAL4hs.PB-driven expression of snS52E.Scer\UAS.P\T.T:Avic\GFP-EGFP fails to rescue the gnarled bristle phenotype exhibited by sn3 mutants.

      (Zanet et al., 2009)
      Images (1)
      Stocks (98)
      Notes on Origin
      Discoverer

      Mohr, 11th June 1922.

      External Crossreferences and Linkouts ( 0 )
      Synonyms and Secondary IDs (3)
      References (42)