The expanded gene was first identified by a spontaneous mutation that causes broad wings. We have identified an enhancer-trap insertion within expanded and used it to generate additional mutations, including one null allele. expanded is an essential gene, necessary for proper growth control of imaginal discs and, when mutant, causes either hyperplasia or degeneration depending on the disc. Wing overgrowth in expanded hypermorphs is limited to specific regions along the anterior-posterior and dorsal-ventral axis. expanded encodes a novel 1429 amino acid protein that is localized to the apical surface of disc cells and contains three potential SH3-binding sites. Together, these observations suggest that the Expanded protein engages in protein-protein interactions regulating cell proliferation in discs.

Reference

Reference
Bennet
R. L.
,
Hoffman
F. M.
(
1992
)
Increased levels of the Drosophilaabelson tyrosine kinase in nerves and muscles: subcellular localization and mutant phenotypes imply a role in cell-cell interactions.
Development
116
,
953
966
Bier
E.
,
Vaessin
H.
,
Shepherd
S.
,
Lee
K.
,
McCall
K.
,
Barbel
S.
,
Ackerman
L.
,
Carretto
R.
,
Uemura
T.
,
Grell
E.
(
1989
)
Searching for pattern and mutation in the Drosophila genome with a P-lacZ vector.
Genes Dev
3
,
1273
1287
Blair
S.
(
1992
)
engrailed expression in the anterior lineage compartment of the developing wing blade of Drosophila.
Development
115
,
21
33
Bonner
T. I.
,
Buckley
N. J.
,
Young
A. C.
,
Brann
M. R.
(
1987
)
Identification of a family of Muscarinic Acetylcholine Receptor genes.
Science
237
,
527
532
Brower
D. L.
(
1986
)
engrailed expression in Drosophila imaginal discs.
EMBO J
5
,
2649
2656
Bryant
P. J.
,
Huettner
B.
,
Held
L. I.
Jr.
,
Ryerse
J.
,
Szidonya
J.
(
1988
)
Mutations at the fat locus interfere with cell proliferation control and epithelial morphogenesis in Drosophila.
Dev. Biol
129
,
541
554
Bryant
P. J.
,
Levinson
P. Y.
(
1985
)
Intrinsic growth control in the imaginal primordia of Drosophila and the autonomous action of a lethal mutation causing overgrowth.
Dev. Biol
107
,
355
363
Bryant
P. J.
,
Schmidt
O.
(
1990
)
The genetic control of cell proliferation in Drosophila imaginal discs.
J. Cell Science
13
,
169
189
Bryant
P. J.
,
Simpson
P.
(
1984
)
Intrinsic and extrinsic control of growth in developing organs.
Quart. Rev. Biol
59
,
387
415
Cavener
D. R.
(
1987
)
Comparison of the consensus sequence flanking translational start sites in Drosophila and vertebrates.
Nucleic Acids Research
15
,
1353
1361
Clark
S. G.
,
Stern
M. J.
,
Horvitz
H. R.
(
1992
)
C. elegans cell signalling gene sem-5 encodes a protein with SH2 and SH3 domains.
Nature
356
,
340
344
Cousso
J. P.
,
Bate
M.
,
Martinez-Arias
A.
(
1993
)
A wingless dependent polar coordinate system in Drosophila imaginal discs.
Science
259
,
484
490
Duchesne
M.
,
Schweighoffer
F.
,
Parker
F.
,
Clerc
F.
,
Frobert
Y.
,
Thang
M. N.
,
Tocque
B.
(
1993
)
Identification of the SH3 domainof GAP as an essential sequence for Ras-GAP-mediated signaling.
Science
259
,
525
528
Franz
W. M.
,
Berger
P.
,
Wang
J. Y. J.
(
1989
)
Deletion of an N-terminal regulatory domain of the c-abl tyrosine kinase activates its oncogenic potential.
EMBO J
8
,
137
147
Gateff
E. A.
,
Mechler
B. M.
(
1989
)
Tumor-suppressor genes of Drosophila melanogaster.
Crit. Rev. Oncogen
1
,
221
245
Huettner
B.
,
Bryant
P. J.
(
1988
)
l(2)ey: lethal(2)eyeless.
Drosophila Information Service
67
,
110
–.
James
A. A.
,
Bryant
P. J.
(
1981
)
Mutations causing pattern deficiencies and duplications in the imaginal wing disk of Drosophila melanogaster.
Dev. Biol
85
,
39
54
Jursnich
V. A.
,
Fraser
S. E.
,
Held
L. I.
Jr.
,
Ryerse
J.
,
Bryant
P. J.
(
1990
)
Defective gap-junctional communication associated with imaginal disc overgrowth and degeneration caused by mutations of the dco gene in Drosophila.
Dev. Biol
140
,
413
429
Klambt
C.
,
Muller
S.
,
Lutzelschwab
R.
,
Rossa
R.
,
Totzke
F.
,
Schmidt
O.
(
1989
)
The Drosophila melanogaster l(2)gl gene encodes a protein homologous to the cadherin cell-adhesion molecule family.
Dev. Biol
133
,
425
436
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
Lutzelschwab
R.
,
Klämbt
C.
,
Rossa
R.
,
Schmidt
O.
(
1987
)
A protein product of the Drosophila recessive tumor gene, lethal(2)giant larvae, potentially has cell adhesion properties.
EMBO J
6
,
1791
1797
Mahoney
P. A.
,
Weber
U.
,
Onofrechuk
P.
,
Biessmann
H.
,
Bryant
P. J.
,
Goodman
C. S.
(
1991
)
The fat tumor suppressor gene in Drosophila encodes a novel member of the cadherin gene superfamily.
Cell
67
,
853
868
Maniatis
T.
,
Hardison
R. C.
,
Lacy
E.
,
Lauer
J.
,
O'Connell
C.
,
Quon
D.
,
Sim
G. K.
,
Efstratiadis
A.
(
1978
)
The isolation of structural genes from libraries of eucaryotic DNA.
Cell
15
,
687
701
Martin
P.
,
Martin
A.
,
Shearn
A.
(
1977
)
Studies of l(3)c43 hs1a polyphasic, temperature-sensitive mutant of Drosophila melanogaster with a variety of imaginal disc defects.
Dev. Biol
55
,
213
232
Massucci
J. D.
,
Miltenberger
R. J.
,
Hoffman
F. M.
(
1990
)
Pattern-specific expression of the Drosophiladecapentaplegic gene in imaginal disks is regulated by 3cis-regulatory elements.
Genes Dev
4
,
2011
2023
Mechler
B. M.
,
Strand
D.
,
Kalmes
A.
,
Merz
R.
,
Schmidt
M.
,
Torok
I.
(
1991
)
Drosophila as a model system for molecular analysis of tumorigenesis.
Environ. Health Perspect
93
,
63
71
Mitchell
P. J.
,
Tjian
R.
(
1989
)
Transcriptional regulation in mammalian cells by sequence-specific DNA binding proteins.
Science
245
,
371
378
O'Brochta
D. A.
,
Bryant
P. J.
(
1987
)
Distribution of S-phase cells during the regeneration of Drosophila imaginal wing discs.
Dev. Biol
119
,
137
142
Pawson
T.
,
Gish
G. D.
(
1992
)
SH2 and SH3 domains: from structure to function.
Cell
71
,
359
362
Ren
R.
,
Mayer
B. J.
,
Cicchetti
P.
,
Baltimore
D.
(
1993
)
M. Boedigheimer and A. Laughon1301expandedand growth control in imaginal discsIdentification of a ten-amino acid proline-rich SH3 binding site.
Science
259
,
1157
1161
Rosenberg
A. H.
,
Lade
B. N.
,
Chui
D.
,
Lin
S.
,
Dunn
J. J.
,
Studier
F. W.
(
1987
)
Vectors for selective expression of cloned DNAs by T7 RNA polymerase.
Gene
56
,
125
135
Ryerse
J. S.
,
Nagel
B. A.
(
1984
)
Gap junction distribution in the Drosophila wing disc mutants vg, l(2)gd, l(3)c43 hs1 , and l(2)gl 4.
Dev. Biol
105
,
396
403
Schubiger
M.
,
Palka
J.
(
1987
)
Changing spatial patterns of DNA replication in the developing wing of Drosophila.
Dev. Biol
123
,
145
153
Shearn
A.
(
1977
)
Mutational dissection of imaginal disc development in Drosophila melanogaster.
Amer. Zool
17
,
585
594
Simpson
P.
,
Carteret
C.
(
1989
)
A study of shaggy reveals spatial domains of expression of achaete-scute alleles on the thorax of Drosophila.
Development
106
,
57
66
Stern
C.
,
Bridges
C. P.
(
1926
)
The mutants on the extreme left arm of chromosome two of Drosophila melanogaster.
Genetics
11
,
503
530
Stewart
M.
,
Murphy
C.
,
Fristrom
J.
(
1972
)
The recovery and preliminary characterization of x-chromosome mutants affecting imaginal discs of Drosophila melanogaster.
Dev. Biol
27
,
71
83
Strand
D.
,
Torok
I.
,
Kalmes
A.
,
Schmidt
M.
,
Merz
R.
,
Mechler
B. M.
(
1991
)
Transcriptional and translational regulation of the expression of the l(2)gl tumor suppressor gene of Drosophila melanogaster.
Adv. Enz. Reg
31
,
339
350
Waddington
C. H.
(
1940
)
The genetic control of wing development in Drosophila.
J. Genetics
41
,
75
139
Williams
J. A.
,
Paddock
S. W.
,
Carroll
S. B.
(
1993
)
Pattern formation in a secondary field: a hierarchy of regulatory genes subdivides the developing Drosophila wing disc into discrete subregions.
Development
117
,
571
584
Woychik
R. P.
,
Maas
R. L.
,
Zeller
R.
,
Vogt
T. F.
,
Leder
P.
(
1990
)
‘Formins’: proteins deduced from the alternative transcripts of the limb deformity gene.
Nature
346
,
850
853
Woods
D. F.
,
Bryant
P. J.
(
1989
)
Molecular cloning of the lethal(1)discs large-1 oncogene of Drosophila.
Dev. Biol
134
,
222
235
Woods
D. F.
,
Bryant
P. J.
(
1991
)
The discs-large tumor suppressor gene of Drosophila encodes a guanylate kinase homolog localized at septate junctions.
Cell
66
,
451
464
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