spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

Right arrow Help viewing high resolution images
Right arrow Return to article
(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.


Figure 3


Fig. 3. Convergent extension of the Drosophila hindgut. (A, parts a,b) Sagittal views show invagination of the posterior midgut (pmg, purple), proctodeal ring (pr, green), and visceral mesoderm (vm, orange) during germ band extension. (A, parts c,d; B) During germ band retraction, the hindgut elongates (yellow, small intestine; green, large intestine). (C) This elongation occurs by circumferential cell intercalation. (D) Elongation is regulated by the JAK/STAT pathway, including the ligand Unpaired (Upd), the receptor Dome (Dome, Domeless or Master of Marelle), JAK (Hop, Hopscotch) and Stat (Stat92E or Marelle). (E) A model for regulation of hindgut convergent extension is shown, in which unpaired (upd) mRNA is expressed in the small intestine (gray), and the encoded protein diffuses posteriorly, establishing a gradient (lavender). Upd activates Stat and positively regulates Stat protein levels, resulting in a Stat protein and activity gradient (blue) that, in turn, regulates circumferential intercalation and the resulting convergent extension. Anterior is to the left in A-C,E. Adapted, with permission, from Lengyel and Iwaki (Lengyel and Iwaki, 2002) and Johansen et al. (Johansen et al., 2003).





Right arrow Return to article