Rough eye is a gain-of-function allele of amos that disrupts regulation of the proneural gene atonal during Drosophila retinal differentiation.
The regular organization of the ommatidial lattice in the Drosophila eye originates in the precise regulation of the proneural gene atonal (ato), which is responsible for the specification of the ommatidial founder cells R8. Here we show that Rough eye (Roi), a dominant mutation manifested by severe roughening of the adult eye surface, causes defects in ommatidial assembly and ommatidial spacing. The ommatidial spacing defect can be ascribed to the irregular distribution of R8 cells caused by a disruption of the patterning of ato expression. Disruptions in the recruitment of other photoreceptors and excess Hedgehog production in differentiating cells may further contribute to the defects in ommatidial assembly. Our molecular characterization of the Roi locus demonstrates that it is a gain-of-function mutation of the bHLH gene amos that results from a chromosomal inversion. We show that Roi can rescue the retinal developmental defect of ato1 mutants and speculate that amos substitutes for some of ato's function in the eye or activates a residual function of the ato1 allele.
Chanut
Françoise
F
Department of Anatomy, University of California, San Francisco, California 94143, USA. chanut@itsa.ucsf.edu
Woo
Katherine
K
Pereira
Shalini
S
Donohoe
Terrence J
TJ
Chang
Shang-Yu
SY
Laverty
Todd R
TR
Jarman
Andrew P
AP
Heberlein
Ulrike
U
D000483:Alleles; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics* / Q000502:physiology; D004843:Epistasis, Genetic; D018507:Gene Expression Regulation, Developmental; D009414:Nerve Growth Factors / Q000235:genetics* / Q000502:physiology; D009419:Nerve Tissue Proteins; D012160:Retina / Q000196:embryology* / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D019076:Transgenes / Q000235:genetics / Q000502:physiology
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; C405512:Amos protein, Drosophila; C082142:ato protein, Drosophila