The C. elegans lag-2 gene is required for several cell-cell interactions that rely on the receptors GLP-1 and LIN-12. In this paper, we report that lag-2 encodes a putative membrane protein with sequence similarity to Drosophila Delta, a proposed ligand for the Notch receptor. Furthermore, we show that the lag-2 promoter drives expression of a reporter protein in the signaling distal tip cell (DTC) of the DTC/germline interaction. By in situ hybridization, we have found that endogenous lag-2 mRNA is present in the DTC but not the germ line. One fusion protein, called LAG-2::beta-gal(intra), rescues a lag-2 null mutant and can be detected in both DTC and germ line. Taking these results together, we propose that lag-2 may encode a signaling ligand for GLP-1/LIN-12 and that the entire LAG-2 protein may be taken up into the receiving cell during induction by GLP-1 and lateral signaling by LIN-12.
REFERENCES
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
Aorian
R. V.
, Levy
A. D.
, Koga
M.
, Oshima
Y.
, Kramer
J. M.
, Sternberg
P. W.
(1993
) Splicing in C. elegans does not require an AG at the 3splice site.
Mol. Cell. Biol
13
, 626
–637
Artavanis-Tsakonas
S.
, Delidakis
C.
, Fehon
R. G.
(1991
) The Notch locus and the cell biology of neuroblast segregation.
Ann. Rev. Genet
7
, 427
–452
Austin
J.
, Kimble
J.
(1987
) glp-1 is required in the germline for regulation of the decision between mitosis and meiosis in C. elegans.
Cell
51
, 589
–599
Austin
J.
, Kimble
J.
(1989
) Transcript analysis of glp-1 and lin-12, homologous genes required for cell interactions during development of C. elegans.
Cell
58
, 565
–571
Brenner
S.
(1974
) The genetics of Caenorhabditis elegans.
Genetics
77
, 71
–94
Cagan
R. L.
, Kramer
H.
, Hart
A.C.
, Zipursky
S. L.
(1992
) The bride of sevenless and sevenless interaction: internalization of a transmembrane ligand.
Cell
69
, 393
–399
Crittenden
S. E.
, Troemel
E.
, Evans
T. C.
, Kimble
J.
(1994
) GLP-1 is localized to the mitotic region of C. elegans germline.
Development,
120
, 2901
–2911
Evans
T. C.
, Crittenden
S. E.
, Kodoyianni
V.
, Kimble
J.
(1994
) Translational control of maternal glp-1 mRNA establishes an asymmetry in the C. elegans embryo.
Cell
77
, 183
–194
Fehon
R. G.
, Kooh
P. J.
, Rebay
I.
, Regan
C.L.
, Xu
T.
, Muskavitch
M. A. T.
, Artavanis-Tsakonas
S.
(1990
) Molecular interactions betweeen the protein products of the neurogenic loci Notch and Delta, two EGF-homolgous genes in Drosophila.
Cell
61
, 523
–534
Fire
A.
, Harrison
S. W.
, Dixon
D.
(1990
) A modular set of lacZ fusion vectors for studying gene expression in Caenorhabditis elegans.
Gene
93
, 189
–198
Fitzgerald
K.
, Wilkinson
H. A.
, Greenwald
I.
(1993
) glp-1 can substitute for lin-12 in specifying cell fate decisions in Caenorhabditis elegans.
Development
119
, 1019
–1027
Fleming
R. J.
, Scottgale
T. N.
, Diederich
R.J.
, Artavanis-Tsakonas
S.
(1990
) The gene Serrate encodes a putative EGF-like transmembrane protein essential for proper ectodermal development in Drosophila melanogaster.
Genes Dev
4
, 2188
–2201
Fortini
M. E.
, Artavanis-Tsakonas
S.
(1993
) Notch, neurogenesis is only part of the picture.
Cell
75
, 1245
–1247
Greenwald
I.
, Rubin
G. M.
(1992
) Making a difference: the role of cell-cell interactions in establishing separate identities for equivalent cells.
Cell
68
, 271
–281
Greenwald
I.
, Sternberg
P. W.
, Horvitz
H. R.
(1983
) The lin-12 locus specifies cell fates in C. elegans.
Cell
34
, 435
–444
Heitzler
P.
, Simpson
P.
(1991
) The choice of cell fate in the epidermis of Drosophila.
Cell
64
, 1083
–1092
Huang
X. Y.
, Hirsh
D.
(1989
) A second trans-spliced RNA leader sequence in the nematode Caenorhabditis elegans.
Proc. Natl. Acad. Sci. USA
86
, 8640
–8644
Kidd
S.
, Kelley
M. R.
, Young
M. W.
(1986
) Sequence of the Notch locus of Drosophila: relationship of the encoded protein to mammalian clotting and growth factors.
Mol. Cell Biol
6
, 3094
–3108
Kimble
J.
, White
J. G.
(1981
) On the control of germ cell development in Caenorhabditiselegans.
Dev. Biol
81
, 208
–219
Kodoyianni
V.
, Maine
E. M.
, Kimble
J.
(1992
) Molecular basis of loss-of-function mutations in the glp-1 gene of Caenorhabditis elegans.
Mol.Biol. Cell
3
, 1199
–1213
Kooh
P. J.
, Fehon
R. G.
, Muskavitch
M. A. T.
(1993
) Implications of dynamic patterns of Delta and Notch expression for cellular interactions during Drosophila development.
Development
117
, 493
–507
Kopczynski
C. C.
, Alton
A. K.
, Fechtel
K.
, Kooh
P.J.
, Muskavitch
M. A. T.
(1988
) Delta, a Drosophila neurogenic gene, is transcriptionally complex and encodes a protein related to blood coagulation factors and epidermal growth factor of vertebrates.
Genes Dev
2
, 1723
–1735
Kramer
H.
, Cagan
R. L.
, Zipursky
S. L.
(1991
) Interaction of bride of sevenless membrane-bound ligand and the sevenless tyrosine-kinase receptor.
Nature
352
, 207
–212
Krause
M.
, Hirsh
D.
(1984
) A trans-spliced leader sequence on actin mRNA in Caenorhabditiselegans.
Cell
49
, 753
–761
Kyte
J.
, Doolittle
R. F.
(1982
) A simple method for displaying the hydropathic character of a protein.
J. Mol. Biol
157
, 105
–132
Lambie
E. J.
, Kimble
J.
(1991
) Two homologous regulatory genes, lin-12 and glp-1, have overlapping functions.
Development
112
, 231
–240
Maine
E. M.
, Kimble
J.
(1993
) Suppressors of glp-1, a gene required for cell communication during development in Caenorhabditiselegans, define a set of interacting genes.
Genetics
135
, 1011
–1022
Mango
S. E.
, Maine
E. M.
, Kimble
J.
(1991
) Carboxy-terminaltruncation activates glp-1 protein to specify vulval fates in Caenorhabditis elegans.
Nature
352
, 811
–815
Mello
C. C.
, Draper
B. W.
, Priess
J. R.
(1994
) The maternal genes apx-1 and glp-1 and establishment of dorsal-ventral polarity in the early C. elegans embryo.
Cell
77
, 95
–106
Mello
C. C.
, Kramer
J. M.
, Stinchcomb
D.
, Ambros
V.
(1991
) Efficient gene transfer inC. elegans: extrachromosomal maintenance and integration of transforming sequences.
EMBOJ
10
, 3959
–3970
Neuman-Silberberg
F. S.
, Schupbach
T.
(1993
) The Drosophila dorsoventral patterning gene gurken produces a dorsally localized RNA and encodes a TGF alpha-like protein.
Cell
75
, 165
–174
Orita
M.
, Suzuki
Y.
, Sekiya
T.
, Hayashi
K.
(1989
) Rapid and sensitive detection of point mutations and DNA polymorphisms using the polymerase chain reaction.
Genomics
5
, 874
–879
Priess
J. R.
, Schnabel
H.
, Schnabel
R.
(1987
) The glp-1 locus and cellular interactions in early C. elegans embryos.
Cell
51
, 610
–611
Rebay
I.
, Fleming
R. J.
, Fehon
R. G.
, Cherbas
P.
, Artavanis-Tsakonas
S.
(1991
) Specific EGF repeats of Notch mediate interactions with Delta and Serrate, implication for Notch as a multifunctional receptor.
Cell
67
, 687
–699
Roehl
H.
, Kimble
J.
(1993
) Control of cell fate in C. elegans by a Glp-1 peptide consisting primarily of ankyrin repeats.
Nature
264
, 632
–635
Rogers
S.
, Wells
R.
, Rechsteiner
M.
(1986
) Amino acid sequences common to rapidly degraded proteins: the PEST hypothesis.
Science
234
, 364
–368
Selander-Sunnerhagen
M.
, Ullner
M.
, Persson
E.
, Teleman
O.
, Stenflo
J.
, Drakenberg
T.
(1992
) How an epidermal growth factor (EGF)-like domain binds calcium.
J. Biol. Chem
267
, 19642
–19649
Seydoux
G.
, Greenwald
I.
(1989
) Cell autonomy of lin-12 function in a cell fate decision in C. elegans.
Cell
57
, 1237
–1245
Sternberg
P. W.
, Horvitz
H. R.
(1991
) Signal transduction during C. elegans vulval induction.
Trends Genet
7
, 366
–371
Struhl
G.
, Fitzgerald
K.
, Greenwald
I.
(1993
) Intrinsic activity of the lin-12 and Notch intracellular domains in vivo.
Cell
74
, 331
–345
Sundaram
M.
, Greenwald
I.
(1993
) Suppressors of a lin-12 hypomorph define genes that interact with both lin-12 and glp-1 in Caenorhabditis elegans.
Genetics
135
, 765
–783
Tax
F. E.
, Yeargers
J.J.
, Thomas
J. H.
(1994
) Sequence of C. elegans lag-2 reveals a cell-signaling domain shared with Delta and Serrate of Drosophila.
Nature
368
, 150
–154
Thomas
U.
, Speicher
S. A.
, Knust
E.
(1991
) The Drosophila gene Serrate encodes an EGF-like transmembrane protein with a complex expression pattern in embryos and wing discs.
Development
111
, 749
–761
Vassin
H.
, Bremer
K. A.
, Knust
E.
, Campos-Ortega
J. A.
(1987
) The neurogenic gene Delta of Drosophila melanogaster is expressed in neurogenic territories and encodes a putative transmembrane protein with EGF-like repeats.
EMBO J
6
, 3431
–3440
von Heijne
G.
(1985
) Signal sequences, the limits of variation.
J. Mol. Biol
184
, 99
–105
Wharton
K. A.
, Johansen
K. M.
, Xu
T.
, Artavanis-Tsakonas
S.
(1985
) Nucleotide sequence from the neurogenic locus Notch implies a gene product which shares homology with proteins containing EFG-like repeats.
Cell
43
, 567
–581
Yochem
J.
, Greenwald
I.
(1989
) glp-1 and lin-12, genes implicated in distinct cell-cell interactions in C. elegans, encode similar transmembrane proteins.
Cell
58
, 553
–563
Yochem
J.
, Weston
K.
, Greenwald
I.
(1988
) The Caenorhabditis elegans lin-12 gene encodes a transmembrane protein with overall similarity to DrosophilaNotch.
Nature
335
, 547
–550
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1994
