scholarly journals Two nested gonadal inductions of the vulva in nematodes

Development ◽  
1997 ◽  
Vol 124 (1) ◽  
pp. 253-259 ◽  
Author(s):  
M.A. Felix ◽  
P.W. Sternberg
Keyword(s):  
Caenorhabditis Elegans ◽  
Nematode Species ◽  
Precursor Cells ◽  
Evolutionary Change ◽  
Cell Interactions ◽  
Cell Fates ◽  
Anchor Cell

How do intercellular signals that pattern cell fates vary in evolution? During nematode vulva development, precursor cells acquire one of three fates in a pattern centered around the gonadal anchor cell. Non-vulval fates are at the periphery, outer and inner vulval fates are towards the center. In Caenorhabditis elegans, the three fates are specified around the same time by an induction by the anchor cell and lateral signaling between the vulva precursor cells. We find that, in three other nematode species (Panagrolaimus, Oscheius and Rhabditella spp.) spanning two families, the centered pattern is obtained by two temporally distinct gonadal inductions. The first induction specifies vulval fates; the second induction specifies the inner vulval fates in a subset of the precursors' daughters. This evolutionary change in the spatiotemporal connectivity of cell interactions allows centering of the pattern between two precursors in Panagrolaimus.

Comparative developmental studies using Oscheius/Dolichorhabditis sp. CEW1 (Rhabditidae)

Nematology ◽  
2000 ◽  
Vol 2 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Marie Delattre ◽  
Marie-Laure Dichtel ◽  
Marie-Anne Félix
Keyword(s):  
Caenorhabditis Elegans ◽  
Genetic Analysis ◽  
Precursor Cells ◽  
Developmental Studies ◽  
Morphological Markers ◽  
Molecular Tools ◽  
Ras Gene ◽  
C Elegans ◽  
Vulval Precursor Cells ◽  
Anchor Cell

AbstractIn order to study the evolution of nematode vulva development, we focus on Oscheius/Dolichorhabditis sp. CEW1 (Rhabditidae) in comparison with Caenorhabditis elegans. In this species, the fates of the vulval precursor cells are determined by two successive nested inductions by the uterine anchor cell (instead of a single one in C. elegans). This hermaphroditic species can be cultured and handled like C. elegans. We review vulva development in this species. We present some molecular tools and the sequence of the Ras gene. This species is amenable to genetic analysis and we discuss the isolation of morphological markers. Afin d’étudier l’évolution du développement de la vulve des nématodes, nous nous concentrons sur l’espèce Oscheius/Dolichorhabditis sp. CEW1 (Rhabditidae) en la comparant à Caenorhabditis elegans. Dans cette espèce, les destinées des cellules précurseurs de la vulve sont déterminées par deux inductions emboîtées provenant de la cellule ancre de l’utérus (au lieu d’une seule chez C. elegans). Cette espèce hermaphrodite peut être élévée et manipulée comme C. elegans. Nous décrivons le développement de la vulve dans cette espèce. Nous présentons des outils moléculaires et la séquence du gène Ras. Les analyses génétiques sont possibles dans cette espèce et nous discutons l’isolement de marqueurs morphologiques.

scholarly journals Genetic Analysis of the Caenorhabditis elegans MAP Kinase Gene mpk-1

Genetics ◽  
1998 ◽  
Vol 150 (1) ◽  
pp. 103-117 ◽  
Author(s):  
Mark R Lackner ◽  
Stuart K Kim
Keyword(s):  
Transcription Factor ◽  
Caenorhabditis Elegans ◽  
Map Kinase ◽  
Double Mutant ◽  
Cell Fates ◽  
Gain Of Function ◽  
Kinase Gene ◽  
Epistasis Analysis ◽  
Anchor Cell ◽  
Ets Transcription Factor

Abstract The Caenorhabditis elegans mpk-1 gene encodes a MAP kinase protein that plays an important role in Ras-mediated induction of vulval cell fates. We show that mutations that eliminate mpk-1 activity result in a highly penetrant, vulvaless phenotype. A double mutant containing a gain-of-function mpk-1 mutation and a gain-of-function mek mutation (MEK phosphorylates and activates MPK-1) exhibits a multivulva phenotype. These results suggest that mpk-1 may transduce most or all of the anchor cell signal. Epistasis analysis suggests that mpk-1 acts downstream of mek-2 (encodes a MEK homolog) and upstream of lin-1 (encodes an Ets transcription factor) in the anchor cell signaling pathway. Finally, mpk-1 may act together with let-60 ras in multiple developmental processes, as mpk-1 mutants exhibit nearly the same range of developmental phenotypes as let-60 ras mutants.

scholarly journals Cell fate patterning during C. elegans vulval development

Development ◽  
1993 ◽  
Vol 119 (Supplement) ◽  
pp. 9-18 ◽  
Author(s):  
Russell J. Hill ◽  
Paul W. Sternberg
Keyword(s):  
Cell Fate ◽  
Short Range ◽  
Precursor Cells ◽  
Cell Fates ◽  
Vulval Development ◽  
C Elegans ◽  
Vulval Precursor Cells ◽  
Combined Action ◽  
Anchor Cell ◽  
Inductive Signal

Precursor cells of the vulva of the C. elegans hermaphrodite choose between two vulval cell fates (1° and 2°) and a non-vulval epidermal fate (3°) in response to three intercellular signals. An inductive signal produced by the anchor cell induces the vulval precursors to assume the 1° and 2° vulval fates. This inductive signal is an EGF-like growth factor encoded by the gene lin-3. An inhibitory signal mediated by lin-15, and which may originate from the surrounding epidermis, prevents the vulval precursors from assuming vulval fates in the absence of the inductive signal. A short range lateral signal, which acts through the gene lin-12, regulates the pattern of 1° and 2° fates assumed by the induced vulval precursors. The combined action of the three signals precisely directs the six vulval precursors to adopt a 3° 3° 2° 1° 2 ° 3° pattern of fates. The amount of inductive signal produced by the anchor cell appears to determine the number or vulval precursors that assume vulval fates. The three induced vulval precursors most proximal to the anchor cell are proposed to adopt the 2° 1° 2° pattern of fates in response to a gradient of the inductive signal and also in response to lateral signalling that inhibits adjacent vulval precursor cells from both assuming the 1° fate.

Asymmetric movements of cytoplasmic components in Caenorhabditis elegans zygotes

Development ◽  
1986 ◽  
Vol 97 (Supplement) ◽  
pp. 15-29
Author(s):  
Susan Strome
Keyword(s):  
Caenorhabditis Elegans ◽  
Cell Types ◽  
Cell Interactions ◽  
Asymmetric Distribution ◽  
Cell Fates ◽  
Internal Factors ◽  
Important Observation ◽  
Determinant Theory ◽  
Cytoplasmic Determinants ◽  
Cell Cell

One of the central problems facing developmental biologists is understanding how the unicellular zygote develops into a multicellular embryo composed of different tissue types. It is now clear that differentiated cell types differ because they express different sets of genes. However, how cells become instructed to express different sets of genes remains a mystery. One popular model for how cell fates are determined invokes the existence and asymmetric distribution of cytoplasmic ‘determinants’ of cell fates (for reviews see Wilson, 1925; Davidson, 1976). According to this model, the developmental programmes of embryonic blastomeres are specified by internal factors that are differentially segregated to different blastomeres during the early cleavages of the zygote. Alternatively, cells may be instructed by extrinsic signals, in which case the positions of cells in the embryo and cell-cell interactions would be important. Observation and manipulation of embryos that show ‘mosaic’ development provide indirect support for the cell determinant theory.

Cell cycle-dependent sequencing of cell fate decisions in Caenorhabditis elegans vulva precursor cells

Development ◽  
1999 ◽  
Vol 126 (9) ◽  
pp. 1947-1956 ◽  
Author(s):  
V. Ambros
Keyword(s):  
Cell Cycle ◽  
Caenorhabditis Elegans ◽  
Cell Fate ◽  
Precursor Cells ◽  
S Phase ◽  
Cycle Phase ◽  
Cell Fates ◽  
Cell Fate Decisions ◽  
Cycle Arrest ◽  
Cycle Dependent

In Caenorhabditis elegans, the fates of the six multipotent vulva precursor cells (VPCs) are specified by extracellular signals. One VPC expresses the primary (1 degrees) fate in response to a Ras-mediated inductive signal from the gonad. The two VPCs flanking the 1 degrees cell each express secondary (2 degrees) fates in response to lin-12-mediated lateral signaling. The remaining three VPCs each adopt the non-vulval tertiary (3 degrees) fate. Here I describe experiments examining how the selection of these vulval fates is affected by cell cycle arrest and cell cycle-restricted lin-12 activity. The results suggest that lin-12 participates in two developmental decisions separable by cell cycle phase: lin-12 must act prior to the end of VPC S phase to influence a 1 degrees versus 2 degrees cell fate choice, but must act after VPC S phase to influence a 3 degrees versus 2 degrees cell fate choice. Coupling developmental decisions to cell cycle transitions may provide a mechanism for prioritizing or ordering choices of cell fates for multipotential cells.

SUP-17, a Caenorhabditis elegans ADAM protein related to Drosophila KUZBANIAN, and its role in LIN-12/NOTCH signalling

Development ◽  
1997 ◽  
Vol 124 (23) ◽  
pp. 4759-4767 ◽  
Author(s):  
C. Wen ◽  
M.M. Metzstein ◽  
I. Greenwald
Keyword(s):  
Caenorhabditis Elegans ◽  
Genetic Analysis ◽  
Extracellular Domain ◽  
Notch Signalling ◽  
Cell Interactions ◽  
Cell Fates ◽  
Cell Ablation ◽  
Adam Family ◽  
Mediate Cell ◽  
Cell Cell

LIN-12/NOTCH proteins mediate cell-cell interactions that specify cell fates. Previous work suggested that sup-17 facilitates lin-12 signalling in Caenorhabditis elegans. Here, we show that sup-17 encodes a member of the ADAM family of metalloproteases. SUP-17 is highly similar to Drosophila KUZBANIAN, which functions in Drosophila neurogenesis, and the vertebrate ADAM10 protein. Furthermore, we show by genetic analysis that the extracellular domain of LIN-12 appears to be necessary for sup-17 to facilitate lin-12 signalling and that sup-17 does not act downstream of lin-12. Finally, we show by cell ablation experiments that sup-17 can act cell autonomously to facilitate lin-12 activity. We discuss the implications of our observations for LIN-12/NOTCH signalling and how our results complement and extend results obtained from genetic analysis of kuz in Drosophila.

scholarly journals The Caenorhabditis elegans lin-12 gene mediates induction of ventral uterine specialization by the anchor cell

Development ◽  
1995 ◽  
Vol 121 (2) ◽  
pp. 263-271 ◽  
Author(s):  
A.P. Newman ◽  
J.G. White ◽  
P.W. Sternberg
Keyword(s):  
Caenorhabditis Elegans ◽  
Cell Fate ◽  
Lateral Inhibition ◽  
Critical Role ◽  
Egg Laying ◽  
Cell Interactions ◽  
The Other ◽  
Cell Type ◽  
Specialized Cell ◽  
Anchor Cell

The anchor cell (AC) of the Caenorhabditis elegans gonad has a critical role in the development of a functional egg-laying system, which is accomplished through cell-cell interactions. Lateral inhibitory lin-12-mediated signaling among two bipotential cells causes one to adopt the ventral uterine precursor (VU) cell fate while the other becomes the AC. The AC then induces formation of vulval tissue. We find that the AC also induces a particular ventral uterine intermediate precursor fate (pi) by a mechanism that is genetically and temporally distinct from vulval induction. This process requires lin-12, but unlike previously described lin-12-mediated decisions, signaling is unidirectional, is between dissimilar cells and does not involve lateral inhibition. The pi fates are necessary for egg laying and appear to produce a distinct specialized cell type. Thus, patterning of the ventral uterus by the AC is crucial to the development of a functional egg-laying system.

scholarly journals Reciprocal EGFR signaling in the anchor cell ensures precise inter-organ connection during Caenorhabditis elegans vulval morphogenesis

Development ◽  
2022 ◽  
Vol 149 (1) ◽  
Author(s):  
Silvan Spiri ◽  
Simon Berger ◽  
Louisa Mereu ◽  
Andrew DeMello ◽  
Alex Hajnal
Keyword(s):  
Caenorhabditis Elegans ◽  
Egf Receptor ◽  
Adherens Junctions ◽  
Egfr Signaling ◽  
Cell Fates ◽  
Vulval Development ◽  
Sequence Of Events ◽  
Epidermal Growth ◽  
Short And Long Term ◽  
Anchor Cell

ABSTRACT During Caenorhabditis elegans vulval development, the uterine anchor cell (AC) first secretes an epidermal growth factor (EGF) to specify the vulval cell fates and then invades the underlying vulval epithelium. By doing so, the AC establishes direct contact with the invaginating primary vulF cells and attaches the developing uterus to the vulva. The signals involved and the exact sequence of events joining these two organs are not fully understood. Using a conditional let-23 EGF receptor (EGFR) allele along with novel microfluidic short- and long-term imaging methods, we discovered a specific function of the EGFR in the AC during vulval lumen morphogenesis. Tissue-specific inactivation of let-23 in the AC resulted in imprecise alignment of the AC with the primary vulval cells, delayed AC invasion and disorganized adherens junctions at the contact site forming between the AC and the dorsal vulF toroid. We propose that EGFR signaling, activated by a reciprocal EGF cue from the primary vulval cells, positions the AC at the vulval midline, guides it during invasion and assembles a cytoskeletal scaffold organizing the adherens junctions that connect the developing uterus to the dorsal vulF toroid. Thus, EGFR signaling in the AC ensures the precise alignment of the two developing organs.

Sign in / Sign up

Export Citation Format

Share Document