Solid phase synthesis of sodium ion channel IS3-4 segment simultaneously using Boc and Fmoc chemistry

摘要

Both IS3 and IS4are two of the six transmembrane segments of the rat brain sodium ion channel [1,2]. Interestingly, induividual IS3 can mediate the ionic conductance in planar lipid bilayers lack of selectivity between sodium and potassium ions [3,4]. On the other hand, IS4, a highly conserved sequence with regular alternation of one positive-charged and two hydrophobic residues, is predicted to play an important role in switching the channel open and close [5,6]. In order to study the interaction between IS3 and IS4, a peptide with 47 residues (IS3-4) was designed by linking IS3 and IS4 with a connecting sequence GRG, and synthesized by a combined strategy, using Boc and Fmoc chemistry.