A structural study of the myristoylated N-terminus of ARF1.
The effect of myristoylation on the 15-amino-acid peptide from the membrane-binding N-terminus of ADP ribosylation factor 1 (ARF1) was studied using neutron diffraction and circular dichroism. A previous study on the non-acylated form indicated that the peptide lies parallel to the membrane, at a shallow depth and in the vicinity of the phosphorylcholine headgroups. It was suggested that the helix does not extend past residue 12, an important consequence for the linking region of the ARF1 protein. In this paper, we show that the result of myristoylation is to increase the helical content reaching the peptide's C-terminus, resulting in the formation of a new hydrophobic face. This increased helicity may augment the entire protein's membrane-binding affinity, indicating that ARF1 effectively has two interdependent membrane-binding motifs.
Harroun
Thad A
TA
National Research Council, Neutron Program for Materials Research, Chalk River Laboratories, Chalk River, ON, Canada K0J 1J0. Thad.Harroun@nrc.gc.ca
Bradshaw
Jeremy P
JP
Balali-Mood
Kia
K
Katsaras
John
J
D020823:ADP-Ribosylation Factor 1 / Q000737:chemistry* / Q000378:metabolism*; D002942:Circular Dichroism; D003903:Deuterium / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D019814:Myristic Acid / Q000378:metabolism*; D010649:Phenylalanine / Q000737:chemistry; D017433:Protein Structure, Secondary
D019814:Myristic Acid; D010649:Phenylalanine; D003903:Deuterium; D020823:ADP-Ribosylation Factor 1