Greg Reeves (NC State)
- Dorsal specifies boundaries of vnd, sog, dpp, etc in a concentration dependent manner.
- dorsal possibly too flat late for sog.
- Live imaging with lightsheet microscopy and dorsal-venus fusion
- requires only 1 copy to fully compliment doral mutant.
- Gradient ‘widens’ at the pole. Cross-section imaging from light-sheet approach
- Fit slope=-.1 If neighbors seperate, would need 1% precision.
- Sog is repressed in end of cc13, comes back de-repressed (snail degrades) and becomes repressed again.
Stuart Newfold … N Takaesu. (Arizona State). Ubiquitatination and dpp signalling. Faf deubiquinates Medea.
- ubiquitination can serve as transient deactivation of Smads (Medea) without degredation.
- Medea maternal is haplo insufficient.
- Faf phenocopies medea (mostly) weaker in materinal
- Dorsal rho lost in faf (and Mad) mutants
- Is there a difference in the ubiquitination rates of phosopho and unphosophorylated medea?
- Bonus (ubiquitin ligase) phenocopies Dorsal hyperactivity.
Hongtao Chen (Small)
- otd activated by sub threshold levels of bcd in ‘flat’ 1x gradient
- otd activated in anterior half (not everywhere) in ‘flat’ 6x gradient
- tested 100 sequences find 30 bcd dependent enhancers. Group 1 head enhancers ‘ACCAcAA’ found in 25 of 26 head but 0 of 16 hb like patterns (group 2). Mediates repression in Group I. Looks like runt repression. 3% shift in endogenous otd. Modified hb enhancer shifts 20%. Suggests multiple cross repressors. (cic also effects boundary)
- all cause substantial effects to engrailed stripes. (fuse then lose).
- Adding more runt sites moves the boundary progressively more anterior (and sharper).
- Runt distribution depends on runt.
Matt (Nir’s lab)
- pattern of dpp activation in the follicle cells follows tkv expression domain. Tkv sequesters dpp nearer the source.
- Misexpression of tkv can repattern dpp signaling to match different species patterns.
Kruoda (Matsuno lab)
- wnt signaling in left right gut assymetry
- arrow mutants have completely random LR assymetry (wnt receptor co-receptor (with frizzled). Ligand is wnt4.
Casso (Tom Kornberg) hedgehog-Notch interactions.
- m-delta and m8 from the Espl complex behave the same in overexpression assay
Pad wing gradient expands and then contracts, when scaled against the size of the wing disk. Normalize for amplitude brk scales.