Lipid anchor
1) Interaction through an amphipathic α-helix parallel to the membrane plane.
2) interaction through a hydrophobic loop.
3) Interaction by binding with lipid anchors to membrane lipids.
4) Electrostatic or ionic interaction with membrane lipids (e.g. via calcium ions).
A lipid anchor (synonym lipid anchorage , membrane anchor ) is the lipid portion in a peripheral membrane protein .
properties
By lipid anchors are membrane-bound proteins (interchangeably peripheral membrane proteins) to a biomembrane attached. The proteins are located on the outside (peripheral) of the membrane with the lipid portion embedded between the membrane lipids , in contrast to transmembrane proteins that span membranes. A lipid anchor limits the function of the anchored protein to the site of anchoring. As lipid anchors, of course, myristylation and palmitoylation , the GPI anchor , as well as various forms of prenylation such as modification with dolichol , farnesylation and geranylgeranylation occur. While a lipid anchor on a protein only slightly increases the affinity of the protein to the membrane, two lipid anchors lead to the firm binding of the protein to the membrane. Some lipid anchors accumulate in certain areas of the cell membrane , e.g. B. GPI anchors in lipid rafts .
In the oncogene Ras , therapies are being investigated to inhibit the lipid anchoring of Ras , which prevents it from developing its oncogenic function.
Individual evidence
- ↑ RM Epand: Biophysical studies of lipopeptide-membrane interactions. In: Biopolymers. Volume 43, number 1, 1997, ISSN 0006-3525 , pp. 15-24, doi : 10.1002 / (SICI) 1097-0282 (1997) 43: 1 <15 :: AID-BIP3> 3.0.CO; 2-3 , PMID 9174409 .
- ↑ F. Tamanoi, J. Lu: Recent progress in developing small molecule inhibitors designed to interfere with ras membrane association: toward inhibiting K-Ras and N-Ras functions. In: The Enzymes. Volume 34 Pt. B, 2013, ISSN 0423-2607 , pp. 181-200, doi : 10.1016 / B978-0-12-420146-0.00008-1 , PMID 25034105 .