IndraLab

Statements


WNT11 activates FZD7. 28 / 28
1 | 27

reach
"It is possible that these subcellular sites of endogenous Wnt11 and Fz7 activity modulate contact persistence of gastrulating cells, similar to the Wnt11 induced Fz7 accumulations in the animal pole assay."

reach
"In sum, Wnt11 induced Fz7 accumulations are associated with a local increase in cell contact persistence, most likely reflecting stronger cell adhesion at these contact sites."

reach
"To test whether Wnt11 induced Fz7 accumulations influence cell morphology or adhesion, we recorded 3D time-lapse videos of cells in the animal pole assay."

reach
"These Wnt11 induced Fz7 accumulations increase cell contact persistence in a manner that is dependent on the activity of Flamingo (Fmi), which is an atypical cadherin, but independent of further downstream signaling by RhoA and Rok2."

reach
"As we observed cell sorting by Fz7 or PAPC supported by Wnt-11 (XREF_FIG) but no degradation or internalization of C-cadherin (XREF_FIG, XREF_FIG, and S2), we speculated that the hindrance of lateral clustering or cis dimerization of C-cadherin might cause reduction in cell adhesion."

reach
"Moreover, Wnt11 induced Fz7-YFP accumulations in a concentration dependent manner, with increased amounts of Wnt11 enhancing both the number and size of Fz7-YFP accumulations (XREF_FIG)."

reach
"Consistent with Wnt11 induced Fz7 accumulations causing increased contact persistence, we found that Fz7 accumulations shrink slower than the cell contacts (XREF_FIG)."

reach
"Collectively, our data strongly suggests that Fmi plays a key role in controlling cell adhesion at sites of Wnt11 induced Fz7 accumulation."

"Consistent with this, xfz7 biochemically and functionally interacts with xwnt11"

reach
"In contrast, high amounts of the slb mutant allele of wnt11 (40 pg mRNA; wnt11 tx226), which encodes an inactive C-terminal truncated version of Wnt11, did not induce Fz7 accumulations (unpublished data)."

reach
"To distinguish between these possibilities, we monitored the effects of Wnt11 induced Fz7 accumulations on cell contact behavior within the animal pole assay when RhoA and Rok activity is decreased."

reach
"To analyze the influence of Wnt11 induced Fz7 accumulation on cell contact persistence, we determined the rate of cell contact shrinkage during separation and the time of cell separation in the presence and absence of Fz7 accumulation (XREF_FIG)."

reach
"Furthermore, we found that Wnt11 and Dsh puncta at cell contact sites display properties similar to Wnt11 induced Fz7 accumulations in the animal pole assay."

reach
"In that study, non canonical Wnt11 was found to induce the local accumulation of Fz7 at " adhesive subdomains " within contact sites, defined by the presence of the atypical cadherin Flamingo (Fmi)."

reach
"As Dsh puncta at the plasma membrane are only partially reduced in slb and wnt11 mutants (XREF_FIG), it is unlikely that all Dsh puncta correspond to endogenous Wnt11 induced Fz7 accumulations."

reach
"Consistent with the analysis in Drosophila, the local accumulation of Fz7 induced by Wnt11 at cell-cell contacts is dependent on Celsr and Fmi proteins in zebrafish [XREF_BIBR]."

reach
"This suggests that Wnt11 induced Fz7 accumulations are sites of Wnt11 activity."

reach
"Taken together, our results suggest that PLD1 acts as a new positive mediator of Wnt and PCP signaling by promoting Wnt11 induced Fz7 endocytosis for precise regulation of Xenopus CE movements."

reach
"51 Similarly in Xenopus, Wnt11 and Fz7 signalling activates rhoA during gastrulation 52 and Cdc42 may mediate the function of Wnt11 and Fz7 in cells undergoing convergent extension."

reach
"This Wnt11 enhancement of contact persistence was considerably smaller than that of Wnt11 induced Fz7 accumulation, an expected result given the small size of Wnt11 puncta (XREF_FIG)."

reach
"Knockdown of Xenopus Ryk results in gastrulation defects with compromised Wnt11 induced Fz7 and Dishevelled (Dvl) endocytosis."

reach
"This suggests that Wnt11 downstream signaling through RhoA and Rok is not directly involved in mediating enhancement of contact persistence by Wnt11 induced Fz7 accumulation."

reach
"To test if Wnt11 induced Fz7 accumulations are sites of local Wnt11 activity, we looked for changes in Dsh localization."

reach
"Importantly, Wnt11 induced Fz7 accumulations at host-host and donor-donor cell contact sites (XREF_FIG; and not depicted), confirming our previous observation (XREF_FIG) that Wnt11 acts both cell-autonomously and nonautonomously."

reach
"To compare the effect of Wnt11 puncta on contact persistence with that of Wnt11 induced Fz7 accumulations, we also expressed Wnt11-YFP and mem-RFP in the animal pole assay."

reach
"In zebrafish, Wnt11 does not induce Fz7 and Dvl endocytosis, but rather stimulates Fz7 and Dvl accumulation on the plasma membrane, raising the possibility that Wnt-Ryk and Wnt-Fz signaling pathways are distinct."

reach
"Thus, a higher level of Wnt11 expression in EB cultured in the presence of FCS than in cells cultured in the SR medium was accompanied by higher number of cells synthesizing its receptor—FZD7, at days 5 and 7 of the culture."
| PMC

reach
"Overall, our observations suggest that Wnt11 induced Fz7 accumulations increase the persistence of cell contacts in the immediate area."