Figure 1.
F2A sequences used for co-expression of fluorescent ‘reporter’ proteins. 2A mediates the co-translational ‘ribosome skipping’ event whilst fused to the upstream capsid protein 1D. Subsequently, 2A is co-translationally cleaved from 1D by an FMD virus proteinase (3Cpro) which (artificially) defines the length of 2A: the functional entity is, however, longer than this 18aa tract. The 3Cpro cleavage is indicated by the solid vertical arrow, the site of the 2A-mediated ribosome skipping event is shown by the open vertical arrow. Versions of various lengths were used by producing truncations of the 58aa version.