Fuente: WIPO "tomato" Methods and compositions are provided for enhancing the accumulation and/or recovery of recombinant casein expressed in soy. Endogenous Casein-Processing Interfering Proteins (CPIPs), such as oxidases like lipoxygenases (LOX), are present in the recombinant protein fractions and interfere with yield and/or purity. RNA interference (RNAi) mechanisms are leveraged in plasmids that knockdown genes expressing CPIPs and/or genes in the Soybean Vesicular Trafficking Pathway (SVTP). Knocking down of two or more target genes is manifested using a dual gene targeting approach, often via a single expression cassette containing multiple distinct shRNA constructs for enhanced efficiency. The shRNA constructs invoke a RNAi mechanism that leads to increased casein accumulation either: (1) directly, by suppressing CPIPs (e.g., LOX) to enable more efficient purification; or (2) indirectly, by modifying SVTP genes to route casein away from lytic vacuoles, preventing degradation.