VitelloTag: a tool for high-throughput cargo delivery into oocytes.

Delivering molecular tools into oocytes is essential for developmental and reproductive biology. Microinjection, the conventional method, is equipment-intensive, often technically challenging, and low-yield, and is impractical in species with delicate oocytes or restricted spawning seasons. To overcome these limitations, we developed VitelloTag, a cost-effective, high-throughput system using vitellogenin-derived fusion proteins to enable efficient cargo delivery via receptor-mediated endocytosis. We demonstrate its utility by delivering Cas9/sgRNA complexes in two distantly related species for gene knockout.