β-Catenin

2022-05-02: reference:

β-Catenin #

Integral part of the WNT pathway. Involved both in cell-cell adhesion and in gene transcription.

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  • The β-Catenin Destruction Complex
    • CK1 initially phosphorylates Ser45 of β-catenin, which primes GSK-3β phosphorylateion of β-Catenin at Thr41. Which then in turn primes phosphorylation of Ser37, and Ser33.

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• When unstimulated (what did I mean by this) GSK-3β phosphorylates β-catenin (Tyr216), whereby it dissociates and then it is ubiquinated.

• When WNT binds to the complex… sometimes you see the complex in a fragmented state - idk. It doesn’t deactivate anything. Idk if it actually gets phosphorylated, but it’s at Ser9 if so, perhaps as opposed to multiple sites.

• If β-Catenin is not phosphorylated, it enters the nucleus to activate target genes. Those include:

  • The transcription factors LEF1/TCF R
    • Hella VGCCs and potassium channels, a few neuroreceptors