Protein constructs and purification to homogeneity by electro-elution.

<p><i>A</i>, Schematic of full length human coilin with line diagrams of bacterially expressed constructs below. RG box denotes the 4 Arg-Gly repeat at amino acids 413–420. Construct names are listed to the left and theoretical iso-electric points with and without GST tag are to the right of each construct line diagram. Diamonds represent mutations to Asp or Glu, mimicking phosphorylation by addition of negative charge. Circles represent mutations of the 4 Arg in the RG box to Gly. <i>B</i>, Coomassie stained SDS PAGE with samples from bacterially expressed proteins purified to homogeneity by electro-elution. <i>C</i>, Coomassie stained SDS PAGE with samples from a control BL-21 purification or bacterially expressed fly coilin protein purified to homogeneity by electro-elution.