Amor J C, Horton J R, Zhu X, Wang Y, Sullards C, Ringe D, Cheng X, Kahn R A
Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322-3050, USA.
J Biol Chem. 2001 Nov 9;276(45):42477-84. doi: 10.1074/jbc.M106660200. Epub 2001 Sep 4.
Structures were determined by x-ray crystallography for two members of the ADP-ribosylation factor (ARF) family of regulatory GTPases, yeast ARF1 and ARL1, and were compared with previously determined structures of human ARF1 and ARF6. These analyses revealed an overall conserved fold but differences in primary sequence and length, particularly in an N-terminal loop, lead to differences in nucleotide and divalent metal binding. Packing of hydrophobic residues is central to the interplay between the N-terminal alpha-helix, switch I, and the interswitch region, which along with differences in surface electrostatics provide explanations for the different biophysical and biochemical properties of ARF and ARF-like proteins.
通过X射线晶体学确定了调节性GTP酶ADP核糖基化因子（ARF）家族的两个成员，即酵母ARF1和ARL1的结构，并与先前确定的人类ARF1和ARF6的结构进行了比较。这些分析揭示了整体保守的折叠，但一级序列和长度的差异，特别是在N端环中，导致了核苷酸和二价金属结合的差异。疏水残基的堆积对于N端α螺旋、开关I和开关间区域之间的相互作用至关重要，这与表面静电的差异一起为ARF和ARF样蛋白的不同生物物理和生化特性提供了解释。
