TEMED catalyzes the decomposition of the persulfate ion to give a free radical (i.e., a molecule with an unpaired electron):

TLS Online TPP Program

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#Unit 4. Cell Communication and Cell Signaling

The palmitoleate attached to the Wnt protein binds to a specific site on the Fz extracellular domain and stabilizes the Wnt-Fz complex.

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#Unit 4. Cell Communication and Cell Signaling

Wnt signal transduction pathways classify into:

1. Canonical wnt pathway (β-catenin dependent)

2. Noncanonical wnt pathways (β-catenin independent)

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#Unit 4. Cell Communication and Cell Signaling

Noncanonical pathways can be divided into two types: 

1. The “planar cell polarity” pathway

2. The “Wnt/calcium” pathway

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#Unit 4. Cell Communication and Cell Signaling

Central player in the canonical Wnt pathway is β-catenin

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#Unit 4. Cell Communication and Cell Signaling

Homologs

β-catenin in vertebrates = Armadillo in Drosophila

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#Unit 4. Cell Communication and Cell Signaling

“canonical” Wnt signaling uses a second TM protein, LRP that associates with Frizzled in a Wnt signal– dependent manner.