The gut of C. elegans derives from all the progeny of the E blastomere, a cell of the eight cell stage. Previous work has shown that gut specification requires an induction during the four cell stage (Goldstein, B. (1992) Nature 357, 255–257). Blastomere isolation and recombination experiments were done to determine which parts of the embryo can respond to gut induction. Normally only the posterior side of the EMS blastomere contacts the inducing cell, P2. When P2 was instead placed in a random position on an isolated EMS, gut consistently differentiated from the daughter of EMS contacting P2, indicating that any side of EMS can respond to gut induction. Additionally, moving P2 around to the opposite side of EMS in an otherwise intact embryo caused EMS's two daughter cells to switch lineage timings, and gut to differentiate from the descendents of what normally would be the MS blastomere. The other cells of the four cell stage, ABa, ABp, and P2, did not form gut when placed in contact with the inducer. To determine whether any other inductions are involved in gut specification, timed blastomere isolations were done at the two and eight cell stages. In the absence of cell contact at the two cell stage, segregation of gut fate proceeded normally at both the two and four cell stages. Gut fate also segregated properly in the absence of cell contact at the eight cell stage. A model is presented for the roles of lineage-dependent mechanisms and cell interactions in establishing gut fate in the E lineage.

Reference

Aamodt
E. J.
,
Chung
M. A.
,
McGhee
J. D.
(
1991
)
Spatial control of gut-specific gene expression during Caenorhabditis elegans development.
Science
252
,
579
582
Albertson
D. G.
(
1984
)
Formation of the first cleavage spindle in nematode embryos.
Dev. Biol
101
,
61
72
Babu
P.
(
1974
)
Biochemical genetics of Caenorhabditis elegans.
Mol. Gen. Genet
135
,
39
44
Babu
P.
,
Siddiqui
S.
(
1980
)
Genetic mosaics of Caenorhabditis elegans: A tissue-specific fluorescent mutant.
Science
210
,
330
332
Bowerman
B.
,
Eaton
B. A.
,
Priess
J. R.
(
1992
)
skn-1, a maternally expressed gene required to specify the fate of ventral blastomeres in the early C. elegans embryo.
Cell
68
,
1061
1075
Bowerman
B.
,
Tax
F. E.
,
Thomas
J. H.
,
Priess
J. R.
(
1992
)
Cell interactions involved in development of the bilaterally symmetrical intestinal valve cells during embryogenesis in Caenorhabditis elegans.
Development
116
,
1112
1122
Brenner
S.
(
1974
)
The genetics of Caenorhabditis elegans.
Genetics
77
,
71
94
Deppe
U.
,
Schierenberg
E.
,
Cole
T.
,
Krieg
C.
,
Schmitt
D.
,
Yoder
B.
,
von Ehrenstein
G.
(
1978
)
Cell lineages of the embryo of the nematode Caenorhabditis elegans.
Proc. Natl. Acad. Sci. USA
75
,
376
380
Edgar
L. G.
,
McGhee
J. D.
(
1986
)
Embryonic expression of a gut-specific esterase in Caenorhabditis elegans.
Dev. Biol
114
,
109
118
Goldstein
B.
(
1992
)
Induction of gut in Caenorhabditis elegans embryos.
Nature
357
,
255
257
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
Hirsh
D.
,
Oppenheim
D.
,
Klass
M.
(
1976
)
Development of the reproductive system of Caenorhabditis elegans.
Dev. Biol
49
,
200
219
Horvitz
H. R.
,
Herskowitz
I.
(
1992
)
Mechanisms of asymmetric cell division: two Bs or not two Bs, that is the question.
Cell
68
,
237
255
Jacobson
A. G.
(
1966
)
Inductive processes in embryonic development.
Science
152
,
25
34
Jessell
T. M.
,
Melton
D. A.
(
1992
)
Diffusible factors in vertebrate embryonic induction.
Cell
68
,
257
270
Jones
E. A.
,
Woodland
H. R.
(
1987
)
The development of animal cap cells in Xenopus: a measure of the start of animal cap competence to form mesoderm.
Development
101
,
557
563
Kemphues
K. J.
,
Priess
J. R.
,
Morton
D. G.
,
Cheng
N.
(
1988
)
Identification of genes required for cytoplasmic localization in early embryos of C. elegans.
Cell
52
,
311
320
Kimble
J.
,
Hirsh
D.
(
1979
)
The post-embryonic cell lineages of the hermaphrodite and male gonads in Caenorhabditis elegans.
Dev. Biol
70
,
396
417
Laufer
J. S.
,
Bazzicalupo
P.
,
Wood
W. B.
(
1980
)
Segregation of developmental potential in early embryos of Caenorhabditis elegans.
Cell
19
,
569
577
Mello
C. C.
,
Draper
B. W.
,
Krause
M.
,
Weintraub
H.
,
Priess
J. R.
(
1992
)
The pie-1 and mex-1 genes and maternal control of blastomere identity in early C. elegans embryos.
Cell
70
,
163
176
Morton
D. G.
,
Roos
J. M.
,
Kemphues
K. J.
(
1992
)
par-4, a gene required for cytoplasmic localization and determination of specific cell types in Caenorhabditis elegans embryogenesis.
Genetics
130
,
771
790
Nigon
V.
,
Guerrier
P.
,
Monin
H.
(
1960
)
L'Architecture polaire de l'oeuf et movements des constituants cellulaires au cour des premieres etapes du developpement chez quelque nematodes.
Bull. Biol. Fr. Belg
94
,
132
201
Priess
J. R.
,
Thomson
J. N.
(
1987
)
Cellular interactions in early C. elegans embryos.
Cell
48
,
241
250
Rose
S. M.
(
1939
)
Embryonic induction in the Ascidia.
Biol. Bull
77
,
216
232
Schierenberg
E.
(
1987
)
Reversal of cellular polarity and early cell-cell interactions in the embryo of Caenorhabditis elegans.
Dev. Biol
122
,
452
463
Siddiqui
S.
,
Babu
P.
(
1980
)
Kynurenine hydroxylase mutants of the nematode Caenorhabditis elegans.
Mol. Gen. Genet
179
,
21
24
Strome
S.
(
1986
)
Fluorescence visualization of the distribution of microfilaments in gonads and early embryos of the nematode Caenorhabditis elegans.
J. Cell Biol
103
,
2241
2252
Strome
S.
,
Wood
W. B.
(
1983
)
Generation of asymmetry and segregation of germ-line granules in early Caenorhabditis elegans embryos.
Cell
35
,
15
25
Sulston
J. E.
,
Horvitz
H. R.
(
1977
)
Post-embryonic cell lineages of the nematode Caenorhabditis elegans.
Dev. Biol
56
,
110
156
Sulston
J. E.
,
Schierenberg
E.
,
White
J. G.
,
Thomson
J. N.
(
1983
)
The embryonic cell lineage of the nematode Caenorhabditis elegans.
Dev. Biol
100
,
64
119
Wood
W. B.
,
Schierenberg
E.
,
Strome
S.
(
1984
)
Localization and determination in early embryos of Caenorhabditis elegans. UCLA Symp.
Mol. Cell. Biol
19
,
37
49
This content is only available via PDF.