Discovering Functional ERK Substrates Regulating Caenorhabditis elegans Germline Development

The Caenorhabditis elegans germline is composed of mitotically dividing cells at the distal end that give rise to meiotic cells more proximally. Specification of the distal region as mitotic relies on induction by the somatic distal tip cell and the glp-1 signal transduction pathway. However, the genetic control over the transition from mitosis to meiosis is not understood. In this paper, we report the identification of a gene, gld-2, that has at least two functions in germline development. First, gld-2 is required for normal progression through meiotic prophase. Second, gld-2 promotes entry into meiosis from the mitotic cell cycle. With respect to this second function, gld-2 appears to be functionally redundant with a previously described gene, gld-1 (Francis, R., Barton, M. K., Kimble, J. and Schedl, T. (1995) Genetics 139, 579–606). Germ cells in gld-1(o) and gld-2 single mutants enter meiosis at the normal time, but germ cells in gld-2 gld-1(o) double mutants do not enter meiosis. Instead, the double mutant germline is mitotic throughout and forms a large tumor. We suggest that gld-1 and gld-2 define two independent regulatory pathways, each of which can be sufficient for entry into meiosis. Epistasis analyses show that gld-1 and gld-2 work downstream of the glp-1 signal transduction pathway. Therefore, we hypothesize that glp-1 promotes proliferation by inhibiting the meiosis-promoting functions of gld-1 and gld-2.

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mRNA localization is linked to translation regulation in the Caenorhabditis elegans germ lineage

10.1101/2020.01.09.900498 ◽

2020 ◽

Cited By ~ 2

Author(s):

Dylan M. Parker ◽

Lindsay P. Winkenbach ◽

Samuel P. Boyson ◽

Matthew N. Saxton ◽

Camryn Daidone ◽

...

Keyword(s):

Caenorhabditis Elegans ◽

Rna Binding ◽

Rna Binding Proteins ◽

Regulatory Control ◽

Translational Repression ◽

Translation Regulation ◽

Germline Development ◽

P Granules ◽

C Elegans ◽

Early Embryos

AbstractCaenorhabditis elegans early embryos generate cell-specific transcriptomes despite lacking active transcription. This presents an opportunity to study mechanisms of post-transcriptional regulatory control. In seeking the mechanisms behind this patterning, we discovered that some cell-specific mRNAs accumulate non-homogenously within cells, localizing to membranes, P granules (associated with progenitor germ cells in the P lineage), and P-bodies (associated with RNA processing). Transcripts differed in their dependence on 3’UTRs and RNA Binding Proteins, suggesting diverse regulatory mechanisms. Notably, we found strong but imperfect correlations between low translational status and P granule localization within the progenitor germ lineage. By uncoupling these, we untangled a long-standing question: Are mRNAs directed to P granules for translational repression or do they accumulate there as a downstream step? We found translational repression preceded P granule localization and could occur independent of it. Further, disruption of translation was sufficient to send homogenously distributed mRNAs to P granules. Overall, we show transcripts important for germline development are directed to P granules by translational repression, and this, in turn, directs their accumulation in the progenitor germ lineage where their repression can ultimately be relieved.SummaryMaternally loaded mRNAs localize non-homogeneously within C. elegans early embryos correlating with their translational status and lineage-specific fates.

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A single histone H1 isoform (H1.1) is essential for chromatin silencing and germline development in Caenorhabditis elegans

Development ◽

10.1242/dev.128.7.1069 ◽

2001 ◽

Vol 128 (7) ◽

pp. 1069-1080 ◽

Cited By ~ 1

Author(s):

M.A. Jedrusik ◽

E. Schulze

Keyword(s):

Caenorhabditis Elegans ◽

Gene Family ◽

Molecular Mechanisms ◽

Histone H1 ◽

Specific Aspect ◽

Polycomb Group ◽

Germline Development ◽

C Elegans ◽

Proliferation And Differentiation ◽

Germline Proliferation

In remarkable contrast to somatic cells, the germline of the nematode Caenorhabditis elegans efficiently silences transgenic DNA. The molecular mechanisms responsible for this have been shown to implicate chromatin proteins encoded by the mes genes (Kelly, W. G. and Fire, A. (1998) Development 125, 2451–2456), of which two are the C. elegans homologs of Polycomb Group gene transcriptional repressors. We have analyzed the contribution of the histone H1 gene family to this specific aspect of germ cells in C. elegans. We show with isotype-specific double stranded RNA-mediated interference (RNAi) that a single member of this gene family (H1.1) is essential for the repression of a silenced reporter-transgene in the germline of hermaphrodites and males, whereas no change is found in the somatic expression of this reporter. Additionally, RNA-mediated interference with H1.1 gene expression can cause a phenotype with severe affection of germline proliferation and differentiation in the hermaphrodite, and even sterility (5%-11% penetrance). These and further features observed in histone H1.1 RNAi experiments are also characteristic of the mes phenotype (Garvin, C., Holdeman, R. and Strome, S. (1998) Genetics 148, 167–185), which is believed to result from the desilencing of genes required for somatic differentiation in the germline. Our observations therefore support this interpretation of the mes phenotype and they identify a single histone H1 isoform (H1.1) as a new component specifically involved in chromatin silencing in the germline of C. elegans.

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An essential role in germline development for a P-granule associated novel protein in the model organism Caenorhabditis elegans and RNAi in the ubiquitous parasitic nematode Ascaris suum

10.32469/10355/9869 ◽

2009 ◽

Author(s):

Ge Gao

Keyword(s):

Caenorhabditis Elegans ◽

Essential Role ◽

Parasitic Nematode ◽

Ascaris Suum ◽

Model Organism ◽

Germline Development ◽

Novel Protein

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Mitochondrial RBP Complex AMG-1/SLRP-1 is Required for Germline Development and Reproductive Success in Caenorhabditis elegans

SSRN Electronic Journal ◽

10.2139/ssrn.3846536 ◽

2021 ◽

Author(s):

Peng Wang ◽

Qiushi Wang ◽

Lianwan Chen ◽

Zheng Cao ◽

Qi Zhang ◽

...

Keyword(s):

Caenorhabditis Elegans ◽

Reproductive Success ◽

Germline Development

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The Polycomb group in Caenorhabditis elegans and maternal control of germline development

Development ◽

10.1242/dev.125.13.2469 ◽

1998 ◽

Vol 125 (13) ◽

pp. 2469-2478 ◽

Cited By ~ 7

Author(s):

I. Korf ◽

Y. Fan ◽

S. Strome

Keyword(s):

Gene Expression ◽

Caenorhabditis Elegans ◽

Polycomb Group ◽

Polycomb Group Proteins ◽

Polycomb Group Protein ◽

Maternal Control ◽

Germline Development ◽

C Elegans ◽

Polycomb Group Genes ◽

Group Protein

Four Caenorhabditis elegans genes, mes-2, mes-3, mes-4 and mes-6, are essential for normal proliferation and viability of the germline. Mutations in these genes cause a maternal-effect sterile (i.e. mes) or grandchildless phenotype. We report that the mes-6 gene is in an unusual operon, the second example of this type of operon in C. elegans, and encodes the nematode homolog of Extra sex combs, a WD-40 protein in the Polycomb group in Drosophila. mes-2 encodes another Polycomb group protein (see paper by Holdeman, R., Nehrt, S. and Strome, S. (1998). Development 125, 2457–2467). Consistent with the known role of Polycomb group proteins in regulating gene expression, MES-6 is a nuclear protein. It is enriched in the germline of larvae and adults and is present in all nuclei of early embryos. Molecular epistasis results predict that the MES proteins, like Polycomb group proteins in Drosophila, function as a complex to regulate gene expression. Database searches reveal that there are considerably fewer Polycomb group genes in C. elegans than in Drosophila or vertebrates, and our studies suggest that their primary function is in controlling gene expression in the germline and ensuring the survival and proliferation of that tissue.

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