Allele Dmel\sn³

General Information
Symbol	Dmel\sn³	Species	D. melanogaster
Name		FlyBase ID	FBal0015773
Feature type	allele	Associated gene	Dmel\sn

Allele class
Mutagen	spontaneous
Recent Updates
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FB2013_03
FB2013_02
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Nature of the Allele
Allele class
Mutagen	spontaneous (Roiha et al., 1988, Cant et al., 1994)
Mutations Mapped to the Genome

Type Location Additional Notes References
Associated Sequence Data
DDBJ / EMBL / GenBank	DNA sequence Protein sequence Name

UniProtKB/Swiss-Prot
UniProtKB/TrEMBL

Progenitor genotype
Nature of the lesion	Statement Reference 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) 0.3 kb deletion in -0.9 to 0.0 kb; coordinates according to Roiha, Rubin and O'Hare (1988)
Carried on aberration	Dp(1;1)Gr
Cytology
Phenotypic Data
Phenotypic Class
	female fertile (Paterson and O'Hare, 1991, Roiha et al., 1988, O'Hare et al., 1998) fertile (Cant et al., 1994) male fertile (Paterson and O'Hare, 1991) neuroanatomy defective \| third instar larval stage (Nagel et al., 2012) viable (Bejsovec and Chao, 2012) visible (He and Adler, 2002, Paterson and O'Hare, 1991, O'Hare et al., 1998, Dickinson and Thatcher, 1997) visible \| recessive (Tilney et al., 2000)
Phenotype Manifest In
	actin filament & neuron (with sn^X2) (Kraft et al., 2006) arista (He and Adler, 2002) denticle (Chanut-Delalande et al., 2006) denticle belt (Dickinson and Thatcher, 1997) lateral multidendritic neuron ldaB \| third instar larval stage (Nagel et al., 2012) macrochaeta (Paterson and O'Hare, 1991, Tilney et al., 1996, Roiha et al., 1988, Cant et al., 1994, O'Hare et al., 1998, Tilney et al., 1995, Guild et al., 2003) macrochaeta \| adult stage (Zanet et al., 2009) microchaeta (Tilney et al., 2000, Tilney et al., 2004, Tilney et al., 1995) microchaeta & actin filament (Tilney et al., 2003) neuron (Kraft et al., 2006) neuron (with sn^X2) (Kraft et al., 2006) wing hair (Guild et al., 2005)
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 sn[3] adults. (Zanet et al., 2009) sn[3] 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 sn[3]/sn[3] 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
Linkouts
Interactions
	Show the genetic interaction network for Enhancers & Suppressors
Phenotypic Class
NOT Enhancer of
Statement Reference sn³ is a non-enhancer of optomotor response defective phenotype of ebo⁶⁷⁸ (Ilius et al., 2007)
NOT Suppressor of
Statement Reference sn³ is a non-suppressor of optomotor response defective phenotype of ebo⁶⁷⁸ (Ilius et al., 2007)
Other
Statement Reference f^36a, sn³ has visible phenotype (Fei et al., 2002)
Phenotype Manifest In
Enhanced by
Statement Reference f^36a, m¹, sn³ has abdominal dorsal trichome phenotype, enhanceable by sha^V15 (Chanut-Delalande et al., 2006) f^36a, m¹, sn³ has abdominal dorsal trichome phenotype, enhanceable by WASp³ (Chanut-Delalande et al., 2006) f^36a, m¹, sn³ has denticle phenotype, enhanceable by sha^V15 (Chanut-Delalande et al., 2006) f^36a, m¹, sn³ has denticle phenotype, enhanceable by WASp³ (Chanut-Delalande et al., 2006) m¹, sn³ has denticle phenotype, enhanceable by f^36a (Chanut-Delalande et al., 2006) sn³ has denticle phenotype, enhanceable by m¹ (Chanut-Delalande et al., 2006) sn³ has macrochaeta phenotype, enhanceable by f^36a (Guild et al., 2003) sn³ has microchaeta & actin filament phenotype, enhanceable by f^36a (Tilney et al., 2003) sn³ has microchaeta phenotype, enhanceable by f^36a (Tilney et al., 2004)
NOT Enhanced by
Statement Reference sn³ has arista phenotype, non-enhanceable by f^36a (He and Adler, 2002)
NOT suppressed by
Statement Reference sn³ has arista phenotype, non-suppressible by f^36a (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 f^36a, 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 macrochaeta phenotype of f^36a (Guild et al., 2003) sn³ is an enhancer of microchaeta & actin filament phenotype of f^36a (Tilney et al., 2003) sn³ is an enhancer of microchaeta phenotype of f^36a (Tilney et al., 2004)
NOT Enhancer of
Statement Reference sn³ is a non-enhancer of arista phenotype of f^36a (He and Adler, 2002) 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)
NOT Suppressor of
Statement Reference sn³ is a non-suppressor of arista phenotype of f^36a (He and Adler, 2002) 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)
Other
Statement Reference f^36a, m¹, sn³ has abdominal dorsal trichome phenotype (Chanut-Delalande et al., 2006) f^36a, sn³ has ocellar bristle phenotype (Fei et al., 2002)
Additional Comments
Genetic Interactions
Statement Reference ebo[678] sn[3] 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 ebo[678] 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 ebo[678] sn[3] 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 ebo[678] sn[3] 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, f^36a triple mutants have small, highly misshapen denticles that are more affected than those of m¹, f^36a or m¹, sn³ double mutants. sn³, m¹, f^36a; sha^V15 and sn³, m¹, f^36a; WASp³ quadruple mutants show further impairment to denticle formation compared to sn³, m¹, f^36a 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, f^36a 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, f^36a; WASp³ quadruple mutants and is even more severe in sn³, m¹, f^36a; sha^V15 mutants in which most dorsal hairs are absent, leaving naked cuticle. (Chanut-Delalande et al., 2006) sn³, f^36a double mutants have bristles that are short, like f^36a mutants, and twisted, like sn³ mutants. (Tilney et al., 2004) In f^36a 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 f^36a, 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 f^36a, 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 f^36a 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 f^36a 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 f^36a flies. The frequency of split bristles is increased by injection of cytochalasin D. Bristle elongation in sn³ f^36a flies is more sensitive to vinblastine than in wild-type flies. (Geng et al., 2000)
Xenogenetic Interactions
Statement Reference
Complementation & Rescue Data
Rescued by	sn³ is rescued by sn^{S52A.Scer\UAS.P\T.T:Avic\GFP-EGFP}/Scer\GAL4^hs.PB (Zanet et al., 2009) sn³ is rescued by sn^{Scer\UAS.P\T.T:Avic\GFP-EGFP}/Scer\GAL4^hs.PB (Zanet et al., 2009)
Not rescued by	sn³ is not rescued by sn^{S52E.Scer\UAS.P\T.T:Avic\GFP-EGFP}/Scer\GAL4^hs.PB (Zanet et al., 2009)
Comments	Scer\GAL4[hs.PB]-driven expression of sn[Scer\UAS.P\T.T:Avic\GFP-EGFP] fully rescues the gnarled bristle phenotype exhibited by sn[3] mutants. Scer\GAL4[hs.PB]-driven expression of sn[S52A.Scer\UAS.P\T.T:Avic\GFP-EGFP] fully rescues the gnarled bristle phenotype exhibited by sn[3] mutants. Scer\GAL4[hs.PB]-driven expression of sn[S52E.Scer\UAS.P\T.T:Avic\GFP-EGFP] fails to rescue the gnarled bristle phenotype exhibited by sn[3] mutants. (Zanet et al., 2009)
Stocks ( 89 )
Bloomington	113 sn³ 147 w¹ sn³ m¹ 1514 w¹ sn³ mit¹ 963 Df(1)KA10, sn³ m¹/FM7c 1740 w¹¹¹⁸ sn³ P{neoFRT}19A
Kyoto	105742 sn³ 101202 w¹ sn³ 105758 w¹ sn³ m¹ 101197 w¹ cv¹ sn³ 101205 w¹¹¹⁸ sn³ P{neoFRT}19A 106145 Df(1)KA10, sn³ m¹/FM7c 106480 w¹¹¹⁸ sn³ P{neoFRT}19A
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Notes on Origin
Discoverer	Mohr, 11th June 1922.

External Crossreferences & Linkouts
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Synonyms & Secondary IDs ( 1 )
Reported As
Symbol Synonym	sn³ (Chanut-Delalande et al., 2006, Fei et al., 2002, Guild et al., 2005, Kraft et al., 2006, Tilney et al., 2004, Zanet et al., 2009, Nagel et al., 2012, Bejsovec and Chao, 2012, Ilius et al., 2007)
Name Synonym
Secondary FlyBase IDs

References ( 34 )

Generate a list of	All references relating to this allele ( 34 )

List References by type	Research paper ( 31 ) Abstract ( 1 ) Book ( 1 ) Stock list ( 1 )
Recent research papers ( 2 )
	Bejsovec and Chao, 2012, Development 139(4): 690--698 crinkled reveals a new role for Wingless signaling in Drosophila denticle formation. [FBrf0217282] Nagel et al., 2012, Development 139(16): 2999--3009 Fascin controls neuronal class-specific dendrite arbor morphology. [FBrf0219030] Show all research papers ...

Allele Dmel\sn3

Allele Dmel\sn³