3-6-13_germ cells and germ plasm

8 materials and methods are available as supporting

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 007). 8. Materials and methods are available as supporting material on Science Online. 9. C. A. Russo, N. Takezaki, M. Nei, Mol. Biol. Evol. 12, 391 (1995). 10. G. Dietzl et al., Nature 448, 151 (2007). 11. K. Keleman, T. Micheler, VDRC project members, Personal communication to FlyBase, FBrf0208510: RNAi-phiC31 construct and insertion data submitted by the Vienna Drosophila RNAi Center (2009); http://fb2010_07. flybase.org/reports/FBrf0208510.html. 12. A. L. Parks et al., Nat. Genet. 36, 288 (2004). 13. C. Joppich, S. Scholz, G. Korge, A. Schwendemann, Chromosome Res. 17, 19 (2009). 14. H. Ida et al., Nucleic Acids Res. 37, 1423 (2009). 15. J. L. Mueller, J. L. Page, M. F. Wolfner, Genetics 175, 777 (2007). Germ cells: Do P granules contain the determinant? Cytoplasmic Partitioning of P Granule Components Is Not Required to Specify the Germline in C. elegans Christopher M. Gallo,* Jennifer T. Wang,* Fumio Motegi, Geraldine Seydoux† Asymmetric segregation of P granules during the first four divisions of the Caenorhabditis elegans embryo is a classic example of cytoplasmic partitioning of germline determinants. It is thought that asymmetric partitioning of P granule components during mitosis is essential to distinguish germline from soma. We have identified a mutant (pptr-1) in which P granules become unstable during mitosis and P granule proteins and RNAs are distributed equally to somatic and germline blastomeres. Despite symmetric partitioning of P granule components, pptr-1 mutants segregate a germline that uniquely expresses P granules during postembryonic development. pptr-1 mutants are fertile, except at high temperatures. Hence, asymmetric partitioning of maternal P granules is not essential to specify germ cell fate. Instead, it may serve to protect the nascent germline from stress. A general characteristic of germ cells 1685. Gallo et al (2010). Science 330, is the rhabditis elegans, germ (P) granules are present presence of cytoplasmic RNA-rich granules called germ granules (1). In Caeno- Germ cells: P granules & PIE-1 segregate to the posterior 16. N. Perrimon, A. Lanjuin, C. Arnold, E. Noll, Genetics 144, 1681 (...
View Full Document

Ask a homework question - tutors are online