PUBLICATION
Direct visualization of the Wntless-induced redistribution of WNT1 in developing chick embryos
- Authors
- Galli, L.M., Santana, F., Apollon, C., Szabo, L.A., Ngo, K., Burrus, L.W.
- ID
- ZDB-PUB-180502-19
- Date
- 2018
- Source
- Developmental Biology 439(2): 53-64 (Journal)
- Registered Authors
- Keywords
- PORCN, WLS, WNT1, WNT3A, WNT7A, chick, eGFP, ectoderm, filopodia, live imaging, mCherry, membrane trafficking, moxGFP, neural crest, palmitoylation, zebrafish
- MeSH Terms
-
- Acyltransferases/metabolism
- Animals
- Chick Embryo
- Chickens/metabolism
- Ectoderm/metabolism
- Embryo, Nonmammalian/metabolism
- Embryonic Development/physiology
- Gene Expression Profiling/methods*
- Gene Expression Regulation, Developmental/genetics
- Green Fluorescent Proteins
- Intracellular Signaling Peptides and Proteins/metabolism
- Lipoylation
- Membrane Proteins/metabolism
- Mice
- Neural Crest/metabolism
- Optical Imaging/methods*
- Protein Processing, Post-Translational
- Wnt Signaling Pathway/genetics
- Wnt Signaling Pathway/physiology
- Wnt1 Protein/metabolism*
- Wnt1 Protein/physiology
- Wnt3A Protein/metabolism
- Zebrafish/metabolism
- PubMed
- 29715461 Full text @ Dev. Biol.
Citation
Galli, L.M., Santana, F., Apollon, C., Szabo, L.A., Ngo, K., Burrus, L.W. (2018) Direct visualization of the Wntless-induced redistribution of WNT1 in developing chick embryos. Developmental Biology. 439(2):53-64.
Abstract
Paracrine Wnt signals are critical regulators of cell proliferation, specification, and differentiation during embryogenesis. Consistent with the discovery that Wnt ligands are post-translationally modified with palmitoleate (a 16 carbon mono-unsaturated fatty acid), our studies show that the vast majority of bioavailable chick WNT1 (cWNT1) produced in stably transfected L cells is cell-associated. Thus, it seems unlikely that the WNT1 signal is propagated by diffusion alone. Unfortunately, the production and transport of vertebrate Wnt proteins has been exceedingly difficult to study as few antibodies are able to detect endogenous Wnt proteins and fixation is known to disrupt the architecture of cells and tissues. Furthermore, vertebrate Wnts have been extraordinarily refractory to tagging. To help overcome these obstacles, we have generated a number of tools that permit the detection of WNT1 in palmitoylation assays and the visualization of chick and zebrafish WNT1 in live cells and tissues. Consistent with previous studies in fixed cells, live imaging of cells and tissues with overexpressed cWNT1-moxGFP shows predominant localization of the protein to a reticulated network that is likely to be the endoplasmic reticulum. As PORCN and WLS are important upstream regulators of Wnt gradient formation, we also undertook the generation of mCherry-tagged variants of both proteins. While co-expression of PORCN-mCherry had no discernible effect on the localization of WNT1-moxGFP, co-expression of WLS-mCherry caused a marked redistribution of WNT1-moxGFP to the cell surface and cellular projections in cultured cells as well as in neural crest and surface ectoderm cells in developing chick embryos. Our studies further establish that the levels of WLS, and not PORCN, are rate limiting with respect to WNT1 trafficking.
Errata / Notes
This article is corrected by ZDB-PUB-220906-109 .
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
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