Developmental Cell
Volume 13, Issue 1, July 2007, Pages 15-28
Journal home page for Developmental Cell

Article
Numb Controls Integrin Endocytosis for Directional Cell Migration with aPKC and PAR-3

https://doi.org/10.1016/j.devcel.2007.05.003Get rights and content
Under an Elsevier user license
open archive

Summary

Migrating cells extend protrusions to establish new adhesion sites at their leading edges. One of the driving forces for cell migration is the directional trafficking of cell-adhesion molecules such as integrins. Here, we show that the endocytic adaptor protein Numb is an important component of the machinery for directional integrin trafficking in migrating cells. Numb binds to integrin-βs and localizes to clathrin-coated structures (CCSs) at the substratum-facing surface of the leading edge. Numb inhibition by RNAi impairs both integrin endocytosis and cell migration toward integrin substrates. Numb is regulated by phosphorylation since the protein is released from CCSs and no longer binds integrins when phosphorylated by atypical protein kinase C (aPKC). Because Numb interacts with the aPKC binding partner PAR-3, we propose a model in which polarized Numb phosphorylation contributes to cell migration by directing integrin endocytosis to the leading edge.

CELLBIO

Cited by (0)

2

Present address: IMBA-Institute of Molecular Biotechnology, Dr. Bohr-Gasse 3, 1030 Vienna, Austria.