Differences in embryonic pattern formation between Caenorhabditis elegans and its close parthenogenetic relative Diploscapter coronatus

We report that four putative germline RNA helicases, GLHs, are components of the germline-specific P granules in Caenorhabditis elegans. GLH-3 and GLH-4, newly discovered, belong to a multi-gene glh family. Although GLHs are homologous to Drosophila VASA, a polar granule component necessary for oogenesis and embryonic pattern formation, the GLHs are distinguished by containing multiple CCHC zinc fingers. RNA-mediated interference (RNAi) reveals the GLHs are critical for oogenesis. By RNAi at 20 degrees C, when either loss of GLH-1 or GLH-4 alone has no effect, loss of both GLH-1 and GLH-4 results in 97% sterility in the glh-1/4(RNAi) offspring of injected hermaphrodites. glh-1/4(RNAi) germlines are under-proliferated and are without oocytes. glh-1/4(RNAi) animals produce sperm; however, spermatogenesis is delayed and the sperm are defective. P granules are still present in glh-1/4(RNAi) sterile worms as revealed with antibodies against the remaining GLH-2 and GLH-3 proteins, indicating the GLHs function independently in P granule assembly. These studies reveal that C.elegans can use GLH-1 or GLH-4 to promote germline development.

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RPK1 and TOAD2 Are Two Receptor-like Kinases Redundantly Required for Arabidopsis Embryonic Pattern Formation

Developmental Cell ◽

10.1016/j.devcel.2007.04.003 ◽

2007 ◽

Vol 12 (6) ◽

pp. 943-956 ◽

Cited By ~ 87

Author(s):

Michael D. Nodine ◽

Ramin Yadegari ◽

Frans E. Tax

Keyword(s):

Pattern Formation ◽

Embryonic Pattern Formation

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Genetic analysis of pattern formation in the Arabidopsis embryo

Development ◽

10.1242/dev.113.supplement_1.27 ◽

1991 ◽

Vol 113 (Supplement_1) ◽

pp. 27-38 ◽

Cited By ~ 9

Author(s):

Gerd Jürgens ◽

Ulrike Mayer ◽

Torres Ruiz Ramon A. ◽

Thomas Berleth ◽

Simon Miséra

Keyword(s):

Pattern Formation ◽

Large Scale ◽

Early Embryo ◽

Flowering Plant ◽

Abnormal Development ◽

Mutant Seedling ◽

Basic Body ◽

Plant Embryo ◽

Embryonic Pattern Formation ◽

Plant Arabidopsis Thaliana

Virtually nothing is known about the mechanisms that generate the basic body pattern in plant embryogenesis. As a first step towards the analysis of pattern formation, we have isolated and begun to characterise putative pattern mutants in the flowering plant, Arabidopsis thaliana. A large-scale screen for morphologically abnormal seedling mutants yielded about 250 lines for further study, and genetic evidence suggests saturation of the genome for this kind of mutation. The phenotypes of putative pattern mutants fall into distinct categories, classes and groups, which may reflect specific aspects of embryonic pattern formation. Mutant seedling phenotypes result from abnormal development in the early embryo. The implications of our findings are discussed with regard to the prospects for a mechanistic understanding of pattern formation in the plant embryo.

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