0. Describe the inductive process that leads to vulval formation in C. elegans and the ablation and genetic experiments that demonstrated these cell-cell interactions. How can you use mosaic analysis to demonstrate the site of action of a given gene? What kinds of proteins are involved in the signaling and reception between the cells involved? How does the control of vulval development in C. elegans parallel the control of mammalian epidermal cell proliferation (e.g., explain the EGF - RTK signaling pathway)?1. What did the frog nuclear cloning experiments of John Gurdon and others tell us about the genome and how it changes during differentiation? What are embryonic stem cells, and how are they important in experimental mouse genetics?
2. Determining that a particular substance can affect the fate of a cell or tissue (e.g., induce the tissue) does not prove that the substance actually performs this function in vivo. What other evidence should be found to suggest the substance is the actual inducing agent? (For example, retinoic acid was for some time believed to be the morphogen of the ZPA (zone of polarizing activity). What do we believe currently is its role in limb pattern formation? What inconsistencies suggested it was unlikely to be the actual morphogen?)
3. Describe the structure of a typical eukaryotic gene. What are enhancers and how do they regulate transcription from the promoter? How do the basal transcription factors TFIID and TFIIH interact with the promoter and RNA Polymerase II to promote transcription? What are the essential features of any transcription factor? Select and describe a specific example of a class of transcription factors: their structural features and example(s) of how a member of the class functions in a specific developmental pathway.
4. Describe in general terms the functions of each class of maternal (anterior, posterior and terminal) and zygotic genes (gap, pair-rule, segment polarity, homeotic selector) in the development of Drosophila. Describe the phenotypes of mutants and the normal pattern of expression in each class of genes to illustrate their functions. Select a specific gene in each class and describe its function, expression pattern of mRNA and protein (if they differ), mutant phenotype, and interactions with other genes.
5. Explain how Sander, Kalthoff and their colleagues' classical embryological experiments with leafhopper and midge foreshadowed N¸sslein-Volhard and Wieschausí experiments identifying mutations that affected Drosophila early development. (For example, their ligature and other experiments suggested that anterior and posterior "organizing centers" were interacting to form the anterior-posterior axis of insects. What is the probable molecular basis for the anterior organizing center based on these experiments and then later from molecular genetic experiments with Drosophila?)
6. A conserved molecular mechanism patterns the anterior-posterior axis of virtually all multicellular animals, from nematodes to flies to vertebrates. Describe the organization and pattern of expression of the homeotic gene complex in a typical animal. Describe how homeotic gene complexes evolved from an original single primordial homeobox gene. What additional changes occurred in evolution in the line leading to the vertebrates?
7. Describe the experiments that have lead to our current understanding of the mechanism(s) of pattern formation in the distal-proximal axis or the anterior-posterior axis of the chick forelimb. Also, what is the nature of the interaction between ectoderm and mesoderm in the growing limb bud?
8. Explain what is meant by the terms "autonomous specification" versus "conditional specification" in development. How are these terms related to "mosaic" and "regulative" development?
9. What is the connection between the grey crescent and the various results Spemann got when he separated various two-cell embryos? What other experiments by Spemann suggested something important was happening during gastrulation?
10. When Hans Spemann and Hilde Mangold performed their famous "organizer" experiment, they transplanted tissue from a darkly pigmented newt into a lightly pigmented host newt. Describe their experiment, its results, and why the use of the differently-colored tissues was critical to the interpretation of these results.
11. Cortical rotation is critical for dorsal-ventral axis formation in the amphibian embryo. Explain the current ideas about how this event creates the d-v axis and experiments that support this hypothesis. Dorsal endoderm (the "Nieuwkoop center") induces the formation of the organizer -- how is this linked to cortical rotation? Explain some of the experiments that led to the development of the concept of the Nieuwkoop center. How was the animal cap assay useful in discovering mesoderm inducing factors such as members of the TGF- beta s u p e r f a m i l y o f p r o t e i n s ? W h a t a r e s o m e o f t h e p r o p e r t i e s o f t h e o r g a n i z e r , a n d w h a t a r e t h e m o l e c u l a r b a s e s o f t h e s e p r o p e r t i e s ? H o w i s t h e " i n d u c t i o n " o f t h e n e u r a l e c t o d e r m p a r a d o x i c a l ( o p p o s i t e i n m e c h a n i s m f r o m w h a t w a s e x p e c t e d ) ?
Nov. 20
1st talk - Veronica Rojas
2nd talk - Arlene Bartolome
3rd talk - Barbra Calantas
1st talk reviewers: Kristina Angelo, Andy Rignes
2nd talk reviewers: Michelle Terrell, Abby Young
3rd talk reviewers: Jon Hodges, Julia Mills
Nov. 27
1st talk - Kristina Angelo
2nd talk - Andy Rignes
3rd talk - Michelle Terrell
4th talk - Abby Young
1st talk reviewers: Pat Echolds, Meg Kelly
2nd talk reviewers: Andrea Altmann, Lindsey Bowman
3rd talk reviewers: Remy DelaPeza, Michaela Haney
4th talk reviewers: Veronica Rojas, Arlene Bartolome
Dec. 4
1st talk - Michaela Haney
2nd talk - Julia Mills
3rd talk - Pat Echolds
4th talk - Meg Kelly
1st talk reviewers: Andrea Altmann, Kristina Angelo
2nd talk reviewers: Barbra Calantas, Jon Hodges
3rd talk reviewers: Abby Young, Remy DelaPeza
4th talk reviewers: Lindsey Bowman, Veronica Rojas
Dec. 11
1st talk - Andrea Altmann
2nd talk - Jon Hodges
3rd talk - Remy DelaPeza
4th talk - Lindsey Bowman
1st talk reviewers: Meg Kelly, Michaela Haney
2nd talk reviewers: Julia Mills, Pat Echolds
3rd talk reviewers: Andy Rignes, Michelle Terrell
4th talk reviewers: Arlene Bartolome, Barbra Calantas
Glossary terms and definitions