Caenorhabditis elegans

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Caenorhabditis elegans
Movie
The elegant roundworm
1mm
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Nematode Parasites
Lymphatic filariasis Onchocerciasis
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The C. elegans Genome
97 Mb (8x yeast) 19,000 genes (3x yeast) 51 have
human homologs
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RNAi
Nile red staining for fat In C. elegans
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The Mechanism of RNAi
Movie
Animation Overview
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ApoptosisProgrammed Cell Death
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Hermaphrodites and Males
20um
XX
XO (1600)
The male has a fancy tail
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Lifecycle
(2n)
Fertilization (2n)
Spermatogenesis (n) Oogenesis (n)
embryo laying
4 larval instars
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Social Interactions
Movie
Sydney (Brenner) likes worms because they wriggle
and you can watch them wriggle -- Frances Crick
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Neural Nets and Behavior
302 cells wire the nervous system
gamma aminobutyric acid (GABA), acetylcholine
(ACh) and dopamine
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Gametogenesis
syncytium
Mitosis
Stem cell
Meiosis
Cellularization
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Transgenesis
Movie
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Mating
Movie
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Sperm Motility
Movie
MSP
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Development
Female Male
Pronuclei
GFPhistone fusion
Movie
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Fate Maps
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Mitosis
Movie
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P-granule Partitioning
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Setting It All Up
Mex-5 Mex-6 Par3/6/aPKC
Pie-1 Par-1 Par-2 P-granules
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Cell Reorganization
Movie
Gastrulation occurs as Ea and Ep descend into the
embryonic mass
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Gastrulation
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Making a Worm - Start to Finish
Movie
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A Few Questions for Thought

• Describe the differences between hermaphrodites
  and males in C. elegans. How are the identities
  determined and how do they each contribute to the
  life history of this organism?
• Describe the process of oogenesis in a syncytial
  ovary.
• What is RNAi? Apoptosis? Gastrulation? Why are
  these processes important in this and other
  organisms?
• What is a fate map? How does it apply to the
  roundworm?
• Compare and contrast (in general terms) mosaic
  and regulatory modes of development
• Develop C. elegans as a specific example of
  mosaic development, explaining how mitotic
  daughters are constrained to different
  developmental fates based upon inheritance.