The stereotyped pattern of veins in the Drosophila wing is generated in response to local EGF signalling. Mutations in the rhomboid (rho) gene, which encodes a sevenpass membrane protein required to enhance signalling transmitted by the EGF receptor (Egfr), inhibit vein development and disrupt the vein pattern. By contrast, net mutations produce ectopic veins in intervein regions. We have cloned the net gene and show that it encodes a basic HLH protein that probably acts as a transcriptional repressor. net and rho are expressed in mutually exclusive patterns during the development of the wing imaginal disc. Lack of net activity causes rho expression to expand, and vice versa. Furthermore, ectopic expression of net or rho results in their mutual repression and thus suppresses vein formation or generates tube-like wings composed of vein-like tissue. Egfr signalling and net exert mutually antagonising activities during the specification of vein versus intervein fate. While Egfr signalling represses net transcription, net exhibits a two-tiered control by repressing rho transcription and interfering with Egfr signalling downstream of Rho. Our results further suggest that net is required to maintain intervein development by restricting Egfr signalling, which promotes vein development, to the Net-free vein regions of the wing disc.

Alifragis
P.
,
Poortinga
G.
,
Parkhurst
S. M.
,
Delidakis
C.
(
1997
)
A network of interacting transcriptional regulators involved in Drosophila neural fate specification revealed by the yeast two-hybrid system.
Proc. Natl. Acad. Sci. USA
94
,
13099
13104
Altschul
S. F.
,
Gish
W.
,
Miller
W.
,
Myers
E. W.
,
Lipman
D. J.
(
1990
)
Basic local alignment search tool.
J. Mol. Biol
215
,
403
410
Artavanis-Tsakonas
S.
,
Simpson
P.
(
1991
)
Choosing a cell fate: a view from the Notch locus.
Trends Genet
7
,
403
408
Artavanis-Tsakonas
S.
,
Muskavitch
M. A. T.
,
Yedvobnick
B.
(
1983
)
Molecular cloning of Notch, a locus affecting neurogenesis in Drosophila melanogaster.
Proc. Natl. Acad. Sci. USA
80
,
1977
1981
Artavanis-Tsakonas
S.
,
Matsuno
K.
,
Fortini
M. E.
(
1995
)
Notch signaling.
Science
268
,
225
232
Barolo
S.
,
Levine
M.
(
1997
)
hairy mediates dominant repression in the Drosophila embryo.
EMBO J
16
,
2883
2891
Biehs
B.
,
Sturtevant
M. A.
,
Bier
E.
(
1998
)
Boundaries in the Drosophila wing imaginal disc organize vein-specific genetic programs.
Development
125
,
4245
4257
Bier
E.
(
1998
)
Localized activation of RTK/MAPK pathways during Drosophila development.
BioEssays
20
,
189
194
Bier
E.
,
Jan
L. Y.
,
Jan
Y. N.
(
1990
)
rhomboid, a gene required for dorsoventral axis establishment and peripheral nervous system development in Drosophila melanogaster.
Genes Dev
4
,
190
203
Brand
A. H.
,
Perrimon
N.
(
1993
)
Targeted gene expression as a means of altering cell fates and generating dominant phenotypes.
Development
118
,
401
415
Campos-Ortega
J. A.
(
1997
)
Neurogenesis in Drosophila: an historical perspective and some prospects.
Perspect. Dev. Neurobiol
4
,
267
271
Campuzano
S.
,
Carramolino
L.
,
Cabrera
C. V.
,
Ruíz-Gomez
M.
,
Villares
R.
,
Boronat
A.
,
Modolell
J.
(
1985
)
Molecular genetics of the achaete-scute gene complex of D. melanogaster.
Cell
40
,
327
338
Cowell
I. G.
(
1994
)
Repression versus activation in the control of gene transcription.
Trends Biochem. Sci
19
,
38
42
Cubadda
Y.
,
Heitzler
P.
,
Ray
R. P.
,
Bourouis
M.
,
Ramain
P.
,
Gelbart
W.
,
Simpson
P.
,
Haenlin
M.
(
1997
)
u-shaped encodes a zinc finger protein that regulates the proneural genes achaete and scute during the formation of bristles in Drosophila.
Genes Dev
11
,
3083
3095
Dawson
S. R.
,
Turner
D. L.
,
Weintraub
H.
,
Parkhurst
S. M.
(
1995
)
Specificity for the hairy/enhancer of split basic helix-loop-helix (bHLH) proteins maps outside the bHLH domain and suggests two separable modes of transcriptional repression.
Mol. Cell. Biol
15
,
6923
6931
de Celis
J. F.
,
Llimargas
M.
,
Casanova
J.
(
1995
)
ventral veinless, the gene encoding the Cf1a transcription factor, links positional information and cell differentiation during embryonic and imaginal development in Drosophila melanogaster.
Development
121
,
3405
3416
de Celis
J. F.
,
de Celis
J.
,
Ligoxygakis
P.
,
Preiss
A.
,
Delidakis
C.
,
Bray
S.
(
1996
)
Functional relationship between Notch, Su(H) and the bHLH genes of the E(spl) complex: the E(spl) genes mediate only a subset of Notch activities during imaginal development.
Development
122
,
2719
2728
de Celis
J. F.
,
Bray
S.
,
García-Bellido
A.
(
1997
)
Notch signalling regulates veinlet expression and establishes boundaries between veins and interveins in the Drosophila wing.
Development
124
,
1919
1928
Delidakis
C.
,
Artavanis-Tsakonas
S.
(
1992
)
The Enhancer of split [E(spl)] locus of Drosophila encodes seven independent helix-loop-helix proteins.
Proc. Natl. Acad. Sci. USA
89
,
8731
8735
Díaz-Benjumea
F. J.
,
García-Bellido
A.
(
1990
)
Behavior of cell mutant for an EGF receptor homologue of Drosophila in genetic mosaics.
Proc. R. Soc. London Biol. Sci
242
,
36
44
Díaz-Benjumea
F. J.
,
Cohen
S. M.
(
1993
)
Interaction between dorsal and ventral cells in the imaginal disc directs wing development in Drosophila.
Cell
75
,
741
752
Ferre-D'Amare
A. R.
,
Prendergast
G. C.
,
Ziff
E. B.
,
Burley
S. K.
(
1993
)
Recognition by Max of its cognate DNA through a dimeric b/HLH/Z domain.
Nature
363
,
38
45
Fisher
A. L.
,
Ohsako
S.
,
Caudy
M.
(
1996
)
The WRPW motif of the hairy -related basic helix-loop-helix repressor proteins acts as a 4-amino-acid transcription repression and protein-protein interaction domain.
Mol. Cell. Biol
16
,
2670
2677
Frei
E.
,
Baumgartner
S.
,
Edström
J.-E.
,
Noll
M.
(
1985
)
Cloning of the extra sex combs gene of Drosophila and its identification by P-element-mediated gene transfer.
EMBO J
4
,
979
987
Fristrom
D.
,
Gotwals
P.
,
Eaton
S.
,
Kornberg
T. B.
,
Sturtevant
M.
,
Bier
E.
,
Fristrom
J. W.
(
1994
)
blistered: a gene required for vein/intervein formation in wings of Drosophila.
Development
120
,
2661
2671
Fu
W.
,
Noll
M.
(
1997
)
The Pax2 homolog sparkling is required for development of cone and pigment cells in the Drosophila eye.
Genes Dev
11
,
2066
2078
Gabay
L.
,
Seger
R.
,
Shilo
B.-Z.
(
1997
)
In situ activation pattern of Drosophila EGF receptor pathway during development.
Science
277
,
1103
1106
García-Bellido
A.
,
de Celis
J. F.
(
1992
)
Developmental genetics of the venation pattern of Drosophila.
Annu. Rev. Genet
26
,
277
304
Guichard
A.
,
Biehs
B.
,
Sturtevant
M. A.
,
Wickline
L.
,
Chacko
J.
,
Howard
K.
,
Bier
E.
(
1999
)
rhomboid and Star interact synergistically to promote EGFR/MAPK signaling during Drosophila wing vein development.
Development
126
,
2663
2676
Guillen
I.
,
Mullor
J. L.
,
Capdevila
J.
,
Sanchez-Herrero
E.
,
Morata
G.
,
Guerrero
I.
(
1995
)
The function of engrailed and the specification of Drosophila wing pattern.
Development
121
,
3447
3456
Hanna-Rose
W.
,
Hansen
U.
(
1996
)
Active repression mechanisms of eukaryotic transcription repressors.
Trends Genet
12
,
229
234
Hidalgo
A.
(
1994
)
Three distinct roles for the engrailed gene in Drosophila wing development.
Curr. Biol
4
,
1087
1098
Hidalgo
A.
(
1998
)
Growth and patterning from the engrailed interface.
Int. J. Dev. Biol
42
,
317
324
Horimoto
K.
,
Yamamoto
H.
,
Yanagi
K.
,
Ohshima
K.
,
Otsuka
J.
(
1994
)
A simple procedure for assigning a sequence motif with an obscure pattern: application to the basic/helix-loop-helix motif.
Protein Eng
7
,
1433
1440
Ishibashi
M.
,
Moriyoshi
K.
,
Sasai
Y.
,
Shiota
K.
,
Nakanishi
S.
,
Kageyama
R.
(
1994
)
Persistent expression of helix-loop-helix factor HES-1 prevents mammalian neural differentiation in the central nervous system.
EMBO J
13
,
1799
1805
Jimenez
G.
,
Paroush
Z.
,
Ish-Horowicz
D.
(
1997
)
Groucho acts as a corepressor for a subset of negative regulators, including Hairy and Engrailed.
Genes Dev
11
,
3072
3082
Karim
F. D.
,
Rubin
G. M.
(
1998
)
Ectopic expression of activated Ras1 induces hyperplastic growth and increased cell death in Drosophila imaginal tissues.
Development
125
,
1
9
Kilchherr
F.
,
Baumgartner
S.
,
Bopp
D.
,
Frei
E.
,
Noll
M.
(
1986
)
Isolation of the paired gene of Drosophila and its spatial expression during early embryogenesis.
Nature
321
,
493
499
Klemenz
R.
,
Weber
U.
,
Gehring
W. J.
(
1987
)
The white gene as a marker in a new P-element vector for gene transfer in Drosophila.
Nucleic Acids Res
15
,
3947
3959
Knust
E.
,
Schrons
H.
,
Grawe
F.
,
Campos-Ortega
J. A.
(
1992
)
Seven genes of the Enhancer of split complex of Drosophila melanogaster encode helix-loop-helix proteins.
Genetics
132
,
505
518
Kornberg
T.
,
Siden
I.
,
O'Farrell
P.
,
Simon
M.
(
1985
)
The engrailed locus of Drosophila: in situ localization of transcripts reveals compartment-specific expression.
Cell
40
,
45
53
Lawrence
P. A.
,
Morata
G.
(
1976
)
Compartments in the wing of Drosophila: A study of the engrailed gene.
Dev. Biol
50
,
321
337
Lecuit
T.
,
Brook
J.
,
Ng
M.
,
Calleja
M.
,
Sun
H.
,
Cohen
S. M.
(
1996
)
Two distinct mechanisms for long-range patterning by Decapentaplegic in the Drosophila wing.
Nature
381
,
387
393
Lunde
K.
,
Biehs
B.
,
Nauber
U.
,
Bier
E.
(
1998
)
The knirps and knirps-related genes organize development of the second wing vein in Drosophila.
Development
125
,
4145
4154
Matakatsu
H.
,
Tadokoro
R.
,
Gamo
S.
,
Hayashi
S.
(
1999
)
Repression of the wing vein development in Drosophila by the nuclear matrix protein Plexus.
Development
126
,
5207
5216
Mechler
B. M.
,
McGinnis
W.
,
Gehring
W. J.
(
1985
)
Molecular cloning of lethal(2)giant larvae, a recessive oncogene of Drosophila melanogaster.
EMBO J
4
,
1551
1557
Milán
M.
,
Baonza
A.
,
García-Bellido
A.
(
1997
)
Wing surface interactions in venation patterning in Drosophila.
Mech. Dev
67
,
203
213
Milán
M.
,
Díaz-Benjumea
F. J.
,
Cohen
S. M.
(
1998
)
Beadex encodes an LMO protein that regulates Apterous LIM-homeodomain activity in Drosophila wing development: a model for LMO oncogene function.
Genes Dev
12
,
2912
2920
Montagne
J.
,
Groppe
J.
,
Guillemin
K.
,
Krasnow
M. A.
,
Gehring
W. J.
,
Affolter
M.
(
1996
)
The Drosophila Serum Response Factor gene is required for the formation of intervein tissue of the wing and is allelic to blistered.
Development
122
,
2589
2597
Murre
C.
,
Bain
G.
,
van Dijk
M. A.
,
Engel
I.
,
Furnari
B. A.
,
Massari
M. E.
,
Matthews
J. R.
,
Quong
M. W.
,
Rivera
R. R.
,
Stuiver
M. H.
(
1994
)
Structure and function of helix-loop-helix proteins.
Biochim. Biophys. Acta
1218
,
129
135
Nellen
D.
,
Burke
R.
,
Struhl
G.
,
Basler
K.
(
1996
)
Direct and long-range action of a DPP morphogen gradient.
Cell
85
,
357
368
Noll
M.
(
1993
)
Evolution and role of Pax genes.
Curr. Opin. Genet. Dev
3
,
595
605
Noll
R.
,
Sturtevant
M. A.
,
Gollapudi
R. R.
,
Bier
E.
(
1994
)
New funtions of the Drosophila rhomboid gene during embryonic and adult development are revealed by a novel genetic method, enhancer piracy.
Development
120
,
2329
2338
Ohsako
S.
,
Hyer
J.
,
Panganiban
G.
,
Oliver
I.
,
Caudy
M.
(
1994
)
Hairy function as a DNA-binding helix-loop-helix repressor of Drosophila sensory organ formation.
Genes Dev
8
,
2743
2755
Paroush
Z.
,
Finley
R. L.
Jr
,
Kidd
T.
,
Wainwright
S. M.
,
Ingham
P. W.
,
Brent
R.
,
Ish-Horowicz
D.
(
1994
)
Groucho is required for Drosophila neurogenesis, segmentation, and sex determination and interacts directly with Hairy-related bHLH proteins.
Cell
79
,
805
815
Phillips
S. E.
(
1994
)
Built by association: structure and function of helix-loop-helix DNA-binding proteins.
Structure
2
,
1
4
Roch
F.
,
Baonza
A.
,
Martín-Blanco
E.
,
García-Bellido
A.
(
1998
)
Genetic interactions and cell behaviour in blistered mutants duringproliferation and differentiation of the Drosophila wing.
Development
125
,
1823
1832
Rørth
P.
(
1996
)
A modular misexpression screen in Drosophila detecting tissue-specific phenotypes.
Proc. Natl. Acad. Sci. USA
93
,
12418
12422
Rubin
G. M.
,
Spradling
A. C.
(
1982
)
Genetic transformation of Drosophila with transposable element vectors.
Science
218
,
348
353
Schneitz
K.
,
Spielmann
P.
,
Noll
M.
(
1993
)
Molecular genetics of aristaless, a prd -type homeo box gene involved in the morphogenesis of proximal and distal pattern elements in a subset of appendages in Drosophila.
Genes Dev
7
,
114
129
Schnepp
B.
,
Grumbling
G.
,
Donaldson
T.
,
Simcox
A.
(
1996
)
Vein is a novel component in the Drosophila epidermal growth factor receptor pathway with similarity to the neuregulins.
Genes Dev
10
,
2302
2313
Simcox
A.
(
1997
)
Differential requirement for EGF-like ligands in Drosophila wing development.
Mech. Dev
62
,
41
50
Simcox
A. A.
,
Grumbling
G.
,
Schnepp
B.
,
Bennington-Mathias
C.
,
Hersperger
E.
,
Shearn
A.
(
1996
)
Molecular, phenotypic, and expression analysis of vein, a gene required for growth of the Drosophila wing disc.
Dev. Biol
177
,
475
489
Sturtevant
M. A.
,
Bier
E.
(
1995
)
Analysis of the genetic hierarchy guiding wing vein development in Drosophila.
Development
121
,
785
801
Sturtevant
M. A.
,
Roark
M.
,
Bier
E.
(
1993
)
The Drosophila rhomboid gene mediates the localized formation of wing veins and interacts genetically with components of the EGF-R signaling pathway.
Genes Dev
7
,
961
973
Sturtevant
M. A.
,
O'Neill
J. W.
,
Bier
E.
(
1994
)
Down-regulation of Drosophila Egf-r mRNA levels following hyperactivated receptor signaling.
Development
120
,
2593
2600
Sturtevant
M. A.
,
Biehs
B.
,
Marin
E.
,
Bier
E.
(
1997
)
The spalt gene links the A/P compartment boundary to a linear adult structure in the Drosophila wing.
Development
124
,
21
32
Tabata
T.
,
Kornberg
T. B.
(
1994
)
Hedgehog is a signaling protein with a key role in patterning Drosophila imaginal discs.
Cell
76
,
89
102
Tabata
T.
,
Schwartz
C.
,
Gustavson
E.
,
Ali
Z.
,
Kornberg
T. B.
(
1995
)
Creating a Drosophila wing de novo, the role of engrailed, and the compartment border hypothesis.
Development
121
,
3359
3369
Tautz
D.
,
Pfeifle
C.
(
1989
)
A non-radioactive in situ hybridization method for the localization of specific RNAs in Drosophila embryos reveals translational control of the segmentation gene hunchback.
Chromosoma
98
,
81
85
Worley
K. C.
,
Wiese
B. A.
,
Smith
R. F.
(
1995
)
BEAUTY: an enhanced BLAST-based search tool that integrates multiple biological information resources into sequence similarity search results.
Genome Res
5
,
173
184
Yu
K.
,
Sturtevant
M. A.
,
Biehs
B.
,
François
V.
,
Padgett
R. W.
,
Blackman
R. K.
,
Bier
E.
(
1996
)
The Drosophila decapentaplegic and short gastrulation genes function antagonistically during adult wing vein development.
Development
122
,
4033
4044
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