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Published byAmani Mussett Modified over 10 years ago
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Chromatin Regulation in the C. elegans Germ Line
MES-4 Chromatin Regulation in the C. elegans Germ Line
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XO XX Dosage compensation in worms: soma germline both Xs are
reduced ~50% Females (=hermaphrodites) can self-fertilize Males arise infrequently; can cross-fertilize germline Xs are not transcribed
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How chromatin is organized…
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H4 H3 H4 H3 The Histone Code N N N N N N methylated Lys 20 silencing
acetylated Lys 8, 12, 16 activating methylated Lys 27 silencing methylated Lys 9 silencing methylated Lys 4, 36 activating
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H2A H3 H2B H4 The nucleosome. Get better resolution! Ref.
Kornberg and Lorch, Cell 1999
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MES-4 binds to just 5 of the 6 chromosomes.
maternal pronucleus paternal pronucleus So I sidetracked to finish up work by Youyi Fong, who showed that the chromatin-binding protein MES-4 was excluded from the X in embryos. Emphasize how exciting this was! I never got back to P granules (although I still think they’re cool). It turns out that MES-4 localization on autosomes corresponds to a specific mark that MES-4 (probably) puts there: it modifies a histone protein - one of the small, basic proteins that form nucleosomes…. MES-4 + DNA DNA alone
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H3-Lys36 di-methylation is on Xs in early embryos.
MES-4 is required for H3-Lys36 di-methylation. 1-cell WT 2mK36 WT mes-4 mes-4
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Chromatography
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Sucrose Gradients
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Gel Electrophoresis
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Antibody Use in Detection of Target Protein
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MES-4 and its homologs NSD1 catalyzes H3 Lys36 and H4 Lys20 methylation in vitro. (Raysam et al., EMBO J 2003)
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C. elegans (MES-4) and C. briggsae (CBG60706) Homologs
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MES-4 and CBG60706
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CB60706 and MES-4 Introns and Exons
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Nucleotide Alignment
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BLAST Amino Acid Alignment Under Default Settings
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