Capsid protein (CA) is the structural component of the virus-like particle (VLP), forming the shell that encapsulates the retrotransposons dimeric RNA genome. The Gag-Pol polyprotein is generated by a +1 ribosomal frameshift. Retrotransposons are mobile genetic entities that are able to replicate via an RNA intermediate and a reverse transcription step. In contrast to retroviruses, retrotransposons are non-infectious, lack an envelope and remain intracellular. Ty4 retrotransposons belong to the copia elements (pseudoviridae). Produced by conventional translation.