The growth regulators warts/lats and melted interact in a bistable loop to specify opposite fates in Drosophila R8 photoreceptors.
Color vision in Drosophila relies on the comparison between two color-sensitive photoreceptors, R7 and R8. Two types of ommatidia in which R7 and R8 contain different rhodopsins are distributed stochastically in the retina and appear to discriminate short (p-subset) or long wavelengths (y-subset). The choice between p and y fates is made in R7, which then instructs R8 to follow the corresponding fate, thus leading to a tight coupling between rhodopsins expressed in R7 and R8. Here, we show that warts, encoding large tumor suppressor (Lats) and melted encoding a PH-domain protein, play opposite roles in defining the yR 8 or pR8 fates. By interacting antagonistically at the transcriptional level, they form a bistable loop that insures a robust commitment of R8 to a single fate, without allowing ambiguity. This represents an unexpected postmitotic role for genes controlling cell proliferation (warts and its partner hippo and salvador) and cell growth (melted).
Mikeladze-Dvali
Tamara
T
Department of Biology, Center for Developmental Genetics, New York University, New York, New York 10003, USA.
Wernet
Mathias F
MF
Pistillo
Daniela
D
Mazzoni
Esteban O
EO
Teleman
Aurelio A
AA
Chen
Ya-Wen
YW
Cohen
Stephen
S
Desplan
Claude
C
D000818:Animals; D002454:Cell Differentiation; D049109:Cell Proliferation; D004330:Drosophila / Q000378:metabolism*; D029721:Drosophila Proteins / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D010641:Phenotype; D010786:Photoreceptor Cells / Q000166:cytology / Q000502:physiology*; D011494:Protein Kinases / Q000378:metabolism*; D012243:Rhodopsin / Q000737:chemistry / Q000378:metabolism
D029721:Drosophila Proteins; D047908:Intracellular Signaling Peptides and Proteins; C505057:melt protein, Drosophila; D012243:Rhodopsin; D011494:Protein Kinases; C093503:wts protein, Drosophila