Non-Invasive dsRNA Delivery via Feeding for Effective Gene Silencing in Teleost Fish: A Novel Approach in the Study of Gene Function Analysis

Abstract

RNA interference is a powerful technique for gene silencing, involving post-transcriptional regulation of gene expression. Successful application of RNAi has been demonstrated in various organisms like nematodes, insects, and oysters by ingesting dsRNA-expressing bacteria. In this study, we attempted a non-invasive feeding method in the marine economy teleost fish,Sebastes schlegelii. To validate the feasibility of this approach inS. schlegelii, we utilized rotifers (Brachionus plicatilis),Artemia nauplii, and commercial pellet feed as vectors to deliverEscherichia colistrain HT115 engineered to express double-stranded RNA (dsRNA), targetingdead end(dnd) gene, known to be important for primordial germ cells (PGCs) migration and proliferation in fish. Our experimental results consistently showed that knockdown of thedndgene effectively inhibited the development of PGCs inS. schlegelii, resulting in gonadal dysplasia and even sex reversal. This study marks a significant advancement in understanding gene function in teleost fish, laying the groundwork for future large-scale research in this field.