Xenbase Image ID: 83705
Size-Sensitive Control of Proteolysis and Protein Distribution in DV Patterning, Related to Figure 7
(A-D') Bisection experiments using β-catenin MO embryos that received a single-blastomere injection at the 16-cell stage. (A), (B), (C), and (D) show a bright field view. (A'), (B'), (C'), and (D') show mCherry fluorescence (tracer for injected cells). Whole embryos are shown at stage 8 in (A) and (A') and stage 13 in (B) and (B'). (C), (D), (C'), and (D') show bisected injected halves in (C) and (C') and noninjected halves in (D) and (D') at stage 13 (bisected at stage 8). With the guide of mCherry fluorescence, the embryo could be reproducibly bisectioned into injected and noninjected halves.
(E) Construction of tagged proteins in these assays.
(F) Distribution of the control protein (secretable alkaline phosphatase produced by injection of 12.5 pg mRNA; NC-SEAP; NC is an epitope tag) in bisected halves (β-catenin-MO injected) at stage 13 equivalent (bisection was done at stage 8). Unlike Chordin (Figure 7B), NC-AP protein accumulation in the injected half (lane 3) was comparable to that in the whole embryo (lane 2).
(G) Distribution of NC-Venus (control free-diffusing protein; produced by injection of 12.5 pg mRNA) in the injected and noninjected halves at the early gastrula stage (soon after bisection; compare with Figure 7E). A substantial level of NC-Venus was detected also on the noninjected side (lane 4).
(H and I) Long-range diffusion of tagged (H) BMP4 and (I) ADMP proteins (produced by injection of 12.5 pg mRNA) to the other side of the embryo.
(J) Schematic of the idea that the level of Sizzled conveys the size information of the embryo. On the basis of the "long-range accumulation and feedback model," it may be also considered that the DV patterning system interprets the embryonic size according to the Sizzled level: in this reverse-angle view, embryos with Sizzled overexpression and depletion are larger and smaller, respectively, in their imaginary sizes judged by the patterning system (brown circles; top), whereas the DV patterns in the real size embryos that we see (black circle; top) correspond to dorsalization and ventralization (bottom).
Image published in: Inomata H et al. (2013)
Copyright © 2013. Image reproduced with permission of the Publisher, Elsevier B. V.
Image source: Published
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