Allele Dmel\crb^11A22

General Information
Symbol	Dmel\crb^11A22	Species	D. melanogaster
Name		FlyBase ID	FBal0001817
Feature type	allele	Associated gene	Dmel\crb
Also Known As	crb², crb^11A, crumbs^11A22

Allele class	loss of function allele, amorphic allele - genetic evidence
Mutagen	ethyl methanesulfonate
Recent Updates
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FB2013_03
FB2013_02
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Nature of the Allele
Allele class	amorphic allele - genetic evidence (Tepass and Knust, 1993, Wodarz et al., 1993) loss of function allele (Pellikka et al., 2002)
Mutagen	ethyl methanesulfonate (Tearle and Nusslein-Volhard, 1987, Tepass and Knust, 1990, Wodarz et al., 1993)
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
Cytology	Polytene chromosomes normal. (Tepass and Knust, 1990)
Phenotypic Data
Phenotypic Class
	cell polarity defective (Dunlop et al., 2004) lethal \| embryonic stage \| recessive (Wodarz et al., 1993, Tepass et al., 1990, Tepass and Knust, 1990) visible \| cell autonomous \| somatic clone (Herranz et al., 2006)
Phenotype Manifest In
	adherens junction (Harris and Peifer, 2004) adherens junction \| embryonic stage 9 (Harris and Peifer, 2005) adherens junction \| embryonic stage 10 (Harris and Peifer, 2005) adherens junction \| somatic clone (Izaddoost et al., 2002) amnioserosa (Grawe et al., 1996) ectoderm (Dunlop et al., 2004) embryonic/first instar larval cuticle (Cox et al., 1996, Tanentzapf and Tepass, 2003) embryonic/larval salivary gland \| embryonic stage (Grawe et al., 1996) embryonic/larval tracheal system \| embryonic stage 17 (Stümpges and Behr, 2011) embryonic epidermis (Grawe et al., 1996) eye photoreceptor cell (Bachmann et al., 2008) eye photoreceptor cell \| somatic clone (Gambis et al., 2011) eye photoreceptor cell stalk (Laprise et al., 2006) eye photoreceptor cell stalk \| cell autonomous \| somatic clone (Johnson et al., 2002) eye photoreceptor cell stalk \| somatic clone (Izaddoost et al., 2002, Pellikka et al., 2002) follicle cell \| somatic clone (Tanentzapf et al., 2000) interommatidial bristle \| somatic clone (Pellikka et al., 2002) ommatidium \| somatic clone (Pellikka et al., 2002) retina \| cell autonomous \| conditional \| somatic clone (Johnson et al., 2002) rhabdomere \| cell autonomous \| somatic clone (Johnson et al., 2002) rhabdomere \| somatic clone (Izaddoost et al., 2002, Pellikka et al., 2002, Gambis et al., 2011) secondary pigment cell \| somatic clone (Pellikka et al., 2002) spot adherens junction (Grawe et al., 1996) tertiary pigment cell \| somatic clone (Pellikka et al., 2002) trachea (Grawe et al., 1996) wing margin \| cell autonomous \| somatic clone (Herranz et al., 2006) wing vein \| cell autonomous \| somatic clone (Herranz et al., 2006) zonula adherens (Grawe et al., 1996, Tepass, 1996, Tanentzapf and Tepass, 2003) zonula adherens & photoreceptor \| somatic clone (Pellikka et al., 2002)
Detailed Description
	Statement Reference Homozygous clones in the adult eye show abnormal rhabdomere morphology and some photoreceptor cells are missing. (Gambis et al., 2011) Stage 17 crb[2] mutant embryos show defects in the transition from luminal liquid-clearance to air-filled airways. Tube size defects and defective airway protein clearance are also seen. No air-filling defects are observed in crb[2] heterozygotes. (Stümpges and Behr, 2011) Homozygous clones in the wing disc do not have a growth advantage or disadvantage; the ratio of mutant clone area: area of the wild-type twin spot is approximately 1. (Genevet et al., 2009) Photoreceptor cells of mutant flies kept in the dark for 13 days do not have a wild-type morphology. The mutants also show severe light-dependent retinal degeneration which can be prevented by raising the flies on a medium lacking vitamin A. (Bachmann et al., 2008) Homozygous clones that cover large areas of the wing can be recovered, indicating that loss of crb function does not compromise cell viability. Homozygous clones in the wing that abut the dorsoventral boundary produce a broadening of the wing margin in a cell-autonomous manner. Homozygous clones in the wing lose wing veins in a cell-autonomous manner. (Herranz et al., 2006) crb[2] mutant photoreceptor cells display shortened stalk membranes that are reduced to approximately 50% of their normal length. (Laprise et al., 2006) The adherens junctions in stage 9 and 10 crb² zygotic mutants fragment and become randomly positioned around the cell cortex and along the basolateral membrane as epidermal cells dissociate. The gut epithelium of crb² mutants maintains basic epithelial structure at stage 10. (Harris and Peifer, 2005) crb²/+ embryos show normal cardiac cell alignment. (Qian et al., 2005) Homozygous embryos show a disruption in ectodermal cell polarity from stage 8. Stage 13 homozygous embryos have a relatively normal central nervous system. (Dunlop et al., 2004) Adherens junctions are fragmented in stage 9 crb² zygotic mutant embryos. (Harris and Peifer, 2004) Most cuticle is absent in mutant embryos and the remaining cuticle forms many small granules. The zonula adherens never assembles from spot adherens junctions. (Tanentzapf and Tepass, 2003) Clones in the eye show lack of rhabdomere elongation. The rhabdomeres remain at the top of the retina and appear thicker than wild-type rhabdomeres. Adherens junctions stretch further basolaterally than in wild type. Those at the distal portion of the retina are variable in size and those that are proximal are discontinuous and thin. The adherens junctions attaching the photoreceptors to the floor of the retina remain relatively intact. (Izaddoost et al., 2002) When flies with eyes containing homozygous clones are kept in constant light conditions for 7 days, the retina shows massive degeneration. This phenotype is not seen under low light conditions, instead their rhabdomeres are thicker and shorter compared to wild-type and are often found in close contact with other rhabdomeres of the same ommatidium. The rhabdomeres fail to reach the basal lamina and extend from the distal pole near the lens to only about one third of the normal length. In addition, the stalk membrane is reduced in length, however the tightly stacked internal structure of the rhabdomere is unaffected. When grown in vitamin A-deficient conditions in continuous light, mutant photoreceptors cells show smaller. thinner rhabdomeres, other morphogenetic defects similar to mutant animals raised on standard medium in the dark. However only minor signs to photoreceptor degeneration is seen. (Johnson et al., 2002) In mutant clones in the eye the ommatidia show minor irregularities in arrangement and interommatidial bristle number and position. Rhabdomere shape, zonula adherens integrity and stalk membrane formation are all affected. Rhabdomeres extend only 40-60% of their normal length and are confined to the distal part of the retina. Secondary and tertiary pigment cells die, though not until well after eclosion. Rhabdomeres are larger than normal and may touch each other. At 50% of pupal development zonula adherens are fragmented though by 70% pd they have mostly recovered. Defects in photoreceptor cells are more pronounced proximally than distally. Photoreceptor cell stalk membrane is 50% shorter than wild type. Even in crb²/+ photoreceptors there is a 10% reduction in stalk membrane length. (Pellikka et al., 2002) Homozygous follicle cell clones induced before formation of the follicular epithelium (FE) may lead to epithelial discontinuities or multilayering defects in posterior follicle cells. Small homozygous follicle clones, induced after the FE has formed, show no morphological defects. (Tanentzapf et al., 2000) arm⁴; crb² double mutants exhibit a severe crb-like cuticle phenotype. (Cox et al., 1996) Epithelial cells of ectodermal origin lose their apicobasal polarity resulting in the loss of epithelial integrity and cell death. Both epidermal and amnioserosa cells of stage 10 lack zonula adherens junctions (ZA) and the number of spot adherens junctions (SAJ) is lower. The structure of all ectodermally derived epithelia is affected to varying extents. (Grawe et al., 1996) First defects in zonula adherens formation are seen at the onset of germband extension on the dorsal side of the embryo in the developing amnioserosa. The distribution of adherens junction material at the apicolateral boundary is more irregular. (Tepass, 1996) Ectopic acridine orange and nile blue staining in epidermis. (Abrams et al., 1993) Strong crb phenotype. Embryos almost completely lack cuticle due to cell death in epidermal primordium. P{lacZ}6-81 enhancer detection line specifically expresses Ecol\lacZ in the tracheal system, and reveals that morphogenetic abnormalities in the developing tracheal system result in a only a few aggregates of tracheal cells. Morphogenetic abnormalities and cell death were detected in the presumptive foregut and hindgut by fkh protein staining. Salivary glands also undergo cell death. (Tepass and Knust, 1990)
External Data
Linkouts
Interactions
	Show the genetic interaction network for Enhancers & Suppressors
Phenotypic Class
Enhancer of
Statement Reference crb^11A22/crb[+] is an enhancer of lethal phenotype of kst¹/kst² (Medina et al., 2002) crb^11A22/crb[+] is an enhancer of lethal phenotype of kst^B1-14.1/kst¹ (Medina et al., 2002) crb^11A22/crb[+] is an enhancer of lethal phenotype of kst^B1-14.1/kst² (Medina et al., 2002) crb^11A22/crb[+] is an enhancer of visible phenotype of CycE^JP (Brumby et al., 2004) crb^11A22 is an enhancer of visible phenotype of Ret^MEN2B.GMR (Read et al., 2005)
NOT Enhancer of
Statement Reference crb^11A22 is a non-enhancer of visible phenotype of Ret^MEN2A.GMR (Read et al., 2005)
NOT Suppressor of
Statement Reference crb^11A22 is a non-suppressor of visible phenotype of Ret^MEN2A.GMR (Read et al., 2005)
Other
Statement Reference crb^11A22, gkt^G85 has cell polarity defective phenotype (Dunlop et al., 2004) crb^11A22/crb[+], gkt^G85 has cell polarity defective phenotype (Dunlop et al., 2004)
Phenotype Manifest In
Suppressed by
Statement Reference crb^11A22 has embryonic/first instar larval cuticle \| germline clone phenotype, suppressible by yrt⁷⁵ (Laprise et al., 2006) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| germline clone \| partially by scrib⁶⁷³/scrib⁶⁷³ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by dlg1[+]/dlg1¹⁴ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by dlg1¹⁴/dlg1¹⁴ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by l(2)gl[+]/l(2)gl⁴ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by l(2)gl[+]/l(2)gl²⁷⁵ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by l(2)gl⁴/l(2)gl⁴ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by l(2)gl²⁷⁵/l(2)gl²⁷⁵ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible \| partially by scrib[+]/scrib⁶⁷³ (Tanentzapf and Tepass, 2003) crb^11A22 has embryonic/first instar larval cuticle phenotype, suppressible by yrt⁷⁵ (Laprise et al., 2006) crb^11A22 has retina \| conditional \| somatic clone \| cell autonomous phenotype, suppressible by BacA\p35^GMR.PH (Johnson et al., 2002) crb^11A22 has zonula adherens phenotype, suppressible \| partially by l(2)gl⁴ (Tanentzapf and Tepass, 2003) crb^11A22 has zonula adherens phenotype, suppressible \| partially by scrib⁶⁷³ (Tanentzapf and Tepass, 2003)
NOT suppressed by
Statement Reference crb^11A22 has eye photoreceptor cell stalk \| somatic clone \| cell autonomous phenotype, non-suppressible by BacA\p35^GMR.PH (Johnson et al., 2002) crb^11A22 has eye photoreceptor cell stalk phenotype, non-suppressible by yrt⁷⁵ (Laprise et al., 2006) crb^11A22 has rhabdomere \| somatic clone \| cell autonomous phenotype, non-suppressible by BacA\p35^GMR.PH (Johnson et al., 2002)
Enhancer of
Statement Reference crb^11A22/crb[+] is an enhancer of embryonic/larval cuticle phenotype of baz⁴ (Shao et al., 2010) crb^11A22/crb[+] is an enhancer of eye phenotype of CycE^JP (Brumby et al., 2004) crb^11A22/crb[+] is an enhancer of eye photoreceptor cell stalk phenotype of kst¹/kst² (Pellikka et al., 2002) crb^11A22/crb[+] is an enhancer of rhabdomere \| somatic clone phenotype of kst¹/kst² (Pellikka et al., 2002) crb^11A22 is an enhancer of eye phenotype of Ret^MEN2B.GMR (Read et al., 2005)
NOT Enhancer of
Statement Reference crb^11A22 is a non-enhancer of eye phenotype of Ret^MEN2A.GMR (Read et al., 2005)
NOT Suppressor of
Statement Reference crb^11A22 is a non-suppressor of eye phenotype of Ret^MEN2A.GMR (Read et al., 2005) crb^11A22 is a non-suppressor of wing disc \| somatic clone phenotype of wts^x1 (Genevet et al., 2009)
Other
Statement Reference crb^11A22, kst¹/kst² has eye photoreceptor cell stalk phenotype (Pellikka et al., 2002) crb^11A22, kst¹/kst² has rhabdomere \| somatic clone phenotype (Pellikka et al., 2002) crb^11A22/crb[+], kst¹/kst² has eye photoreceptor cell stalk phenotype (Pellikka et al., 2002) crb^11A22/crb[+], kst¹/kst² has rhabdomere \| somatic clone phenotype (Pellikka et al., 2002) crb^11A22/crb[+], wus^G0162 has embryonic/larval tracheal system \| embryonic stage 17 phenotype (Stümpges and Behr, 2011) Df(3L)H99, crb^11A22 has presumptive embryonic salivary gland phenotype (Xu et al., 2008)
Additional Comments
Genetic Interactions
Statement Reference Transheterozygous wus[G0162] crb[2] stage 17 embryos show defects in in the transition from luminal liquid-clearance to air-filled airways. (Stümpges and Behr, 2011) The cuticle phenotype of dead embryos derived from baz[4]/+ embryos derived from a cross of baz[4]/+ females to wild-type males is enhanced if the females also carry one copy of crb[11A22]. (Shao et al., 2010) The growth advantage of wts[x1] clones in the wing disc over their wild-type twin spots is not affected if the clones are also homozygous for crb[2]. (Genevet et al., 2009) 68.7% of salivary glands fail to invaginate, 25.6% partially invaginate and 5.7% completely invaginate in crb[2] Df(3L)H99 double mutant embryos. (Xu et al., 2008) The loss of wing margin and wing vein thickening seen in Df(1)N-8/+ animals is suppressed by crb[2]/+. (Herranz et al., 2006) yrt[75], crb[2] double mutant photoreceptor cells show shortened stalk membranes. There is no significant difference between stalk length in double mutants compared to crb[2] single mutants. yrt[75] suppresses the cuticle phenotype of crb[2] maternal or zygotic mutant embryos. Defects in junctional integrity and cellular organization of the epidermis are strongly rescued in double mutants compared to crb[2] mutant embryos. (Laprise et al., 2006) 96% of sli²/+, crb²/+ embryos show normal cardiac cell alignment. (Qian et al., 2005) gkt^G85/gkt^G85 ; crb²/+ embryos show a severe disruption in epithelial polarity at stage 11. (Dunlop et al., 2004) l(2)gl⁴ shows marked rescue of the crb² phenotype, as the majority of the cuticle is restored in the double mutant embryos. Embryos lacking both crb and scrib maternal and zygotic function (derived from scrib⁶⁷³ crb² homozygous germline clones) have a phenotype similar to that of embryos derived from scrib⁶⁷³ homozygous germline clones (lacking scrib maternal and zygotic function). Formation of the zonula adherens is largely rescued in crb² ; l(2)gl⁴ or crb² scrib⁶⁷³ double mutant embryos. crb² ; Df(3L)H99 double mutant embryos have crb-mutant like cuticle defects, but the number of cuticle vesicles produced is greatly increased compared to crb² single mutants. These cuticle vesicles have a normal junctional complex containing a zonula adherens and a septate junction. (Tanentzapf and Tepass, 2003) The addition of BacA\p35^GMR.PH to crb² animals suppresses the light sensitive degeneration phenotype seen in mutant clones in the eye, though the phenotypes associated with low light conditions remain. (Johnson et al., 2002) crb²/crb⁺, kst¹/kst² mutants have normal zonula adherens but photoreceptor stalk membranes are much shorter than in wild type, kst homozygous or crb heterozygous photoreceptor cells. (Pellikka et al., 2002)
Xenogenetic Interactions
Statement Reference
Complementation & Rescue Data
Fails to complement	crb^j1B5 (Moussian, 2000.12.7) crb^S010409 (Harden et al., 2002) crb^S025807b (Harden et al., 2002) crb^S025817 (Harden et al., 2002) crb^S025819 (Harden et al., 2002) crb^S050920 (Harden et al., 2002)
Rescued by	crb^11A22 is rescued by crb^+t33 (Tepass et al., 1990) crb^11A22 is rescued by Scer\GAL4^{Scer\FRT.Act5C}/crb^{Scer\UAS.intra.T:Hsap\MYC} (Li et al., 2008) crb^11A22 is rescued by Scer\GAL4^unspecified/crb^{intra.Scer\UAS.T:Hsap\MYC} (Wodarz et al., 1995)
Partially rescued by	crb^11A22 is partially rescued by crb^intra.GMR (Johnson et al., 2002)
Not rescued by	crb^11A22 is not rescued by Scer\GAL4^{Scer\FRT.Act5C}/crb^{intra.SV40.3'UTR.Scer\UAS} (Li et al., 2008)
Comments
Stocks ( 2 )
Bloomington	3448 ru¹ h¹ th¹ st¹ cu¹ sr¹ e^s crb^11A22 ca¹/TM3, Sb¹ Ser¹
Kyoto	107045 ru¹ h¹ th¹ st¹ cu¹ sr¹ e^s crb^11A22 ca¹/TM3, Sb¹ Ser¹
Notes on Origin
Discoverer

Comments
	The phenotype of amorphic crb mutants is essentially the same as the phenotype of amorphic sdt mutants. Embryos doubly mutant for sdt and crb mutants show the same phenotype as embryos singly mutant for either gene. Double mutants for Egfr and sdt or crb show an enhancement of the sdt or crb mutant phenotype. Phenotype can be alleviated by a duplication for sdt⁺, Dp(1;2)sn⁺72d. (Tepass and Knust, 1993) Strong crb allele. (Tepass and Knust, 1990)
External Crossreferences & Linkouts
Other Crossreferences

Linkouts

Synonyms & Secondary IDs ( 5 )
Reported As
Symbol Synonym	crb² (Harris and Peifer, 2004, Harris and Peifer, 2005, Shao et al., 2010, Morais-de-Sá et al., 2010, Ling et al., 2010, Stümpges and Behr, 2011) crb^11A22 (Qian et al., 2005, Dunlop et al., 2004, Harden et al., 2002, Nam and Choi, 2003, Tanentzapf and Tepass, 2003, Johnson et al., 2002, Izaddoost et al., 2002, Pellikka et al., 2002, Fusse and Hoch, 2002, Hong et al., 2001, Lu et al., 2001, Tanentzapf et al., 2000, Brodsky et al., 2000, Klebes and Knust, 2000, Yu et al., 1999, Nordstrom et al., 1996, Tepass, 1996, Cox et al., 1996, Grawe et al., 1996, Knust et al., 1993, Wodarz et al., 1993, Abrams et al., 1993, Tepass and Knust, 1993, Tepass and Knust, 1990, Tepass et al., 1990, Bachmann et al., 2001, Fletcher et al., 2012, Campbell et al., 2009, Herranz et al., 2006, Xu et al., 2008, Laprise et al., 2006, Li et al., 2008, Bachmann et al., 2008, Wang and Riechmann, 2007, Krahn et al., 2010, Huang et al., 2009, Horne-Badovinac and Bilder, 2008, ) crb^11a22 (Genevet et al., 2009) crb^11A (Jack and Myette, 1999, Pereira et al., 1995, Wodarz et al., 1995, Tearle and Nusslein-Volhard, 1987, ) crumbs^11A22 (Medina et al., 2002, Gambis et al., 2011)
Name Synonym
Secondary FlyBase IDs

References ( 54 )

Generate a list of	All references relating to this allele ( 54 )

List References by type	Research paper ( 50 ) Review ( 1 ) Personal communication to FlyBase ( 2 ) Stock list ( 1 )
Recent research papers ( 3 )
	Fletcher et al., 2012, Curr. Biol. 22(12): 1116--1122 Positive feedback and mutual antagonism combine to polarize crumbs in the Drosophila follicle cell epithelium. [FBrf0218646] Gambis et al., 2011, Dev. Biol. 351(1): 128--134 Two-color in vivo imaging of photoreceptor apoptosis and development in Drosophila. [FBrf0213000] Stümpges and Behr, 2011, FEBS Lett. 585(20): 3316--3321 Time-specific regulation of airway clearance by the Drosophila J-domain transmembrane protein Wurst. [FBrf0216409] Show all research papers ...
Recent reviews (0)
	All reviews listed in FlyBase were published before 2011 Show reviews ...

Allele Dmel\crb11A22

Allele Dmel\crb^11A22