DnaA-ATP binds to short repeated sequences and forms an oligomeric com plex that melts DNA

TLS Online TPP Program

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#Unit 4. Cell Communication and Cell Signaling

Structure of Wnt proteins 

22 cysteine residues, which form disulfide bridges that maintain a globular secondary structure.

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#Unit 4. Cell Communication and Cell Signaling

Wnt = wingless + integrated

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#Id: 9960

#Unit 4. Cell Communication and Cell Signaling

Wnt proteins are modified by linkage of a monounsaturated fatty acid, palmitoleic acid, to a serine in the middle of the protein.

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#Id: 9961

#Unit 4. Cell Communication and Cell Signaling

Lipid modifications of Wnt are catalyzed by the 

O-acetyltransferase Porcupine.

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#Unit 4. Cell Communication and Cell Signaling

Principal signaling receptor is Frizzled (Fz), contains 

7 TM α helices.

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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.