There are four known forces that are involved in evolution:

1)mutation,

2) genetic drift

3) gene flow or migration

4) selection.

TLS Online TPP Program

#Id: 9967

#XL - T Zoology

Homologs

β-catenin in vertebrates = Armadillo in Drosophila

TLS Online TPP Program

#Id: 9968

#XL - T Zoology

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

TLS Online TPP Program

#Id: 9969

#XL - T Zoology

Homologs

LRP in vertebrates = Arrow in Drosophila

TLS Online TPP Program

#Id: 9970

#XL - T Zoology

In the absence of Wnts,

“free” β-catenin are targeted for degradation by a cytosolic destruction complex that is held together by the tumor suppressor protein Axin.

TLS Online TPP Program

#Id: 9971

#XL - T Zoology

β-catenin Destruction Complex contains:

Tumor suppressor APC

Dvl protein

Constitutively active protein kinases GSK 3β and CK1

TLS Online TPP Program

#Id: 9972

#XL - T Zoology

Kinases CK1 and GSK3,

sequentially phosphorylate β-catenin at multiple serine and threonine residues