Abstract:
:Ras is a membrane-anchored signaling protein that serves as a hub for many signaling pathways and also plays a prominent role in cancer. The intrinsic behavior of Ras on the membrane has captivated the biophysics community in recent years, especially the possibility that it may form dimers. In this article, we describe results from a comprehensive series of experiments using fluorescence correlation spectroscopy and single-molecule tracking to probe the possible dimerization of natively expressed and fully processed K-Ras4B in supported lipid bilayer membranes. Key to these studies is the fact that K-Ras4B has its native membrane anchor, including both the farnesylation and methylation of the terminal cysteine, enabling detailed exploration of possible effects of cholesterol and lipid composition on K-Ras4B membrane organization. The results from all conditions studied indicate that full-length K-Ras4B lacks intrinsic dimerization capability. This suggests that any lateral organization of Ras in living cell membranes likely stems from interactions with other factors.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Chung JK,Lee YK,Denson JP,Gillette WK,Alvarez S,Stephen AG,Groves JTdoi
10.1016/j.bpj.2017.10.042subject
Has Abstractpub_date
2018-01-09 00:00:00pages
137-145issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(17)31205-5journal_volume
114pub_type
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