Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2009-10-20
pubmed:abstractText
Ras proteins regulate cell growth, differentiation, and apoptosis from various cellular platforms. We have recently identified a novel potential signaling platform, the rasosome, which moves rapidly near the plasma membrane (PM) and in the cytosol, carrying multiple copies of palmitoylated Ras proteins. In the present study we demonstrate that rasosomes are unique entities distinct from PM nanoclusters or from endocytotic compartments. In addition, we examine whether rasosomes can act as regulated Ras signaling platforms. We show that a single rasosome simultaneously carries different types of Ras molecules in their active and inactive state, suggesting that rasosomes can upload and download Ras signals. Total internal reflection fluorescence (TIRF) microscopy combined with fast time-lapse and a new spatial analysis algorithm demonstrate that rasosome movement near the PM is restricted to distinctive areas, rasosomal 'hotspots', localized between actin filament cages. In addition, Ras-binding domain of Raf-1 (RBD) is recruited to Ras in rasosomal hotspots as revealed by bimolecular fluorescence complementation experiments. Interestingly, epidermal growth factor stimulates H/NRas activation on rasosomes and the subsequent recruitment of RBD to rasosomes. Moreover, we show that rasosomes are loaded with Ras downstream effectors and modulators. These findings establish that physiological stimulation originating from PM hotspots is transduced to rasosomes, which appear to serve as robust Ras signaling platforms that spread signals across the cell.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1793
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1691-702
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Rasosomes spread Ras signals from plasma membrane 'hotspots'.
pubmed:affiliation
Department of Neurobiology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, 69978 Tel Aviv, Israel.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't