We discovered that the expression of gammaretroviral gag-only results in a distinct reduction of Pr65Gag compared to gag-pol. We found out that the efficient expression of gag-only depends on the pol sequence, acting in cis and on RNA level. The pol sequence contributes to the nuclear export and stability of the unspliced transcript. We showed that the major impact of the pol sequence is promoting the association of mRNA with polyribosomes and subsequent efficient translation. We observed that the overexpression of the nuclear adaptor SRp20 renders gag-only pol sequence-independent. We engineered to SRp20 mutants that either lack the RRM or the Tap-binding motif. Both domains are crucial for SRp20 function. We showed that gammaretroviruses encode for both, multiple RNA subelements that recruit initially SRp20 and subsequently the nuclear receptor Tap/p15, and a CTE-like element that recruits Tap/p15 directly. These RNA subelements facilitate the nuclear export and translation of gammaretroviral mRNA.