Affordable Access

Publisher Website

BMPs: Conserved Morphogens in Neural Patterning

Authors
Journal
PLoS Biology
1544-9173
Publisher
Public Library of Science
Publication Date
Volume
4
Issue
10
Identifiers
DOI: 10.1371/journal.pbio.0040346
Keywords
  • Synopsis
  • Development
  • Evolution
  • Genetics/Genomics/Gene Therapy
  • Neuroscience
  • Drosophila
  • Chicken
Disciplines
  • Biology
  • Chemistry
  • Medicine

Abstract

PLBI0410_1651-1668.indd PLoS Biology | www.plosbiology.org 1651 Synopses of Research Articles October 2006 | Volume 4 | Issue 10 | e359 | e364 Fusion of two plasma membranes is central to exocytosis, the process by which a cell secretes neurotransmitters, digestive enzymes, and other products. If you believe the simple diagrams in introductory biology textbooks, you’d think this fusion occurs as soon as two membranes touch. Not so—in fact, membrane fusion requires interaction among a complex set of proteins in the membranes, collectively termed SNARE proteins. SNAREs are assisted by a second group, called SM proteins, which bind to them and help promote their functions. Among the SM proteins, one, called Munc18-1, has stood out as something of an oddball. When the others bind to their respective SNAREs, they leave the SNAREs in an open conformation, available for interacting with others and forming the complexes that drive membrane fusion. In contrast, Munc18-1 appears to fold its SNARE, syntaxin 1, into a closed conformation, making it unavailable for binding to other SNAREs. But this result has been obtained only in membrane- free solutions, and the behavior of membrane-bound Munc18-1 has been a mystery. A new study by Felipe Zilly, Thorsten Lang, and colleagues resolves the mystery of the syntaxin–Munc18- 1 interaction and explains how their binding promotes interactions with other SNAREs. The authors performed their experiments in sheets of membrane, prepared by disrupting cells, which mimic the native biochemical environment of Munc18-1 much better than membrane-free solutions. First they showed that syntaxin must be able to close to bind Munc18-1; when mutated to prevent closure, syntaxin bound virtually no Munc18-1. But proteins are fl exible molecules, and it is possible that syntaxin needn’t stay closed while it is bound to Munc18- 1, and that adopting a more open conformation while bound would promote its linkage

There are no comments yet on this publication. Be the first to share your thoughts.