Amphipathic Lipid Packing Sensor (ALPS) motifs were first identified in 2005 in ARFGAP1[1][2] and have been reviewed.[3][4]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/5/5e/ALPSc.jpg/220px-ALPSc.jpg)
The curving of a phospholipid bilayer, for example into a liposome, causes disturbances to the packing of the lipids on the side of the bilayer that has the larger surface area (the outside of a liposome for example). The less "ordered" or "looser" packing of the lipids is recognized by ALPS motifs.
ALPS motifs are 20 to 40 amino acid long portions of proteins that have important collections of types of amino acid residues. Bulky hydrophobic amino acid residues, such as Phenylalanine, Leucine, and Tryptophan are present every 3 or 4 positions, with many polar but uncharged amino acid residues such as Glycine, Serine and Threonine between. The ALPS is unstructured in solution but folds as an alpha helix when associated with the membrane bilayer, such that the hydrophobic residues insert between loosely packed lipids and the polar residues point toward the aqueous cytoplasm.
References
edit- ^ Bigay J, Casella JF, Drin G, Mesmin B, Antonny B (July 2005). "ArfGAP1 responds to membrane curvature through the folding of a lipid packing sensor motif". The EMBO Journal. 24 (13): 2244–53. doi:10.1038/sj.emboj.7600714. PMC 1173154. PMID 15944734.
- ^ Drin G, Casella JF, Gautier R, Boehmer T, Schwartz TU, Antonny B (February 2007). "A general amphipathic alpha-helical motif for sensing membrane curvature". Nature Structural & Molecular Biology. 14 (2): 138–46. doi:10.1038/nsmb1194. PMID 17220896. S2CID 11377393.
- ^ Bradshaw RA, Stahl PD (2015). Encyclopedia of Cell Biology (1st ed.). Cambridge MA: Academic Press. p. 206. ISBN 978-0123944474.
- ^ Vanni S, Vamparys L, Gautier R, Drin G, Etchebest C, Fuchs PF, Antonny B (February 2013). "Amphipathic lipid packing sensor motifs: probing bilayer defects with hydrophobic residues". Biophysical Journal. 104 (3): 575–84. Bibcode:2013BpJ...104..575V. doi:10.1016/j.bpj.2012.11.3837. PMC 3566459. PMID 23442908.
- ^ Horchani H, de Saint-Jean M, Barelli H, Antonny B (2014). "Interaction of the Spo20 membrane-sensor motif with phosphatidic acid and other anionic lipids, and influence of the membrane environment". PLOS ONE. 9 (11): e113484. Bibcode:2014PLoSO...9k3484H. doi:10.1371/journal.pone.0113484. PMC 4245137. PMID 25426975.