Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents

This Article Full Text (PDF, 800K) PPT slides of all figures Alert me when this article is cited Services Email this article Similar articles in this journal Alert me to new content in the JCB Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by LeBrasseur, N. Search for Related Content PubMed Articles by LeBrasseur, N. Social Bookmarking                            What's this?

Speed from recycling

Integrin 6 (green) is returned to the cell surface from recycling endosomes (red).

On page 545, Strachan and Condic show that neural crest cells (NCCs) can be speedy if they remember to recycle receptors. The speed gained from their conservation efforts may expose them to differentiation pathways that other NCCs miss out on.

Populations of NCCs differ in their speed on various matrices. Cranial NCCs, for instance, pick up speed on higher concentrations on laminin, whereas trunk NCCs keep a slow pace. The new results show that the cranial population is able to move quickly because they both recycle and reduce the numbers of their laminin-binding integrin receptors.

More laminin might actually slow cells by promoting strong adhesions. But cranial NCCs avoided this slowdown by removing laminin receptors (integrin 6) from the cell surface. The removed 6 receptors were internalized into recycling endosomes and sent back to the surface. Through this recycling pathway, receptors that are freed from adhesions at the trailing edge may be quickly moved to the leading edge, where new adhesions are needed. Indeed, inhibition of 6 receptor recycling slowed NCC migration on high concentrations of laminin, but had no affect on low laminin levels.

On fibronectin, which binds to integrin 5, the surface levels of integrins 5 and 6 were unchanged, and 5 recycling was not increased. The lack of 5 recycling may explain why the speed of cranial NCCs does not vary based on fibronectin concentrations.

Integrin recycling may explain in part how some sets of NCCs acquire their fate. Upon emerging from the neural tube, NCCs migrate throughout the body and differentiate into cell types as varied as bone, nerves, and pigment cells. NCCs that move quickly on laminin may receive one set of differentiation instructions at their destination. By the time latecomers arrive, the environment may have changed such that these NCCs are told to adopt a different fate.

Nicole LeBrasseur

lebrasn{at}rockefeller.edu

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This Article Full Text (PDF, 800K) PPT slides of all figures Alert me when this article is cited Services Email this article Similar articles in this journal Alert me to new content in the JCB Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by LeBrasseur, N. Search for Related Content PubMed Articles by LeBrasseur, N. Social Bookmarking                            What's this?