Developing a Versatile Shotgun Cloning Strategy for Single-Vector-Based Multiplex Expression of Short Interfering...

Area of Science:

• Molecular Biology
• Gene Regulation
• Biotechnology

Background:

• RNA interference (RNAi) is a key post-transcriptional gene silencing mechanism utilizing short-interfering RNA (siRNA).
• Effective RNAi often requires multiple siRNAs per gene, presenting a time-consuming challenge in research and therapeutic development.

Purpose of the Study:

• To develop a user-friendly, single-vector system for multiplex siRNA expression.
• To facilitate efficient gene function studies and the development of RNAi-based therapeutics.

Main Methods:

• Engineered a BstXI-based shotgun cloning (BSG) system with entry vectors and a retroviral destination vector.
• Utilized restriction enzyme BstXI for seamless assembly of multiple siRNA expression units (SiEUs).
• Constructed multiplex siRNA vectors targeting β-catenin and Smad4 in mesenchymal stem cells (MSCs).

Main Results:

• Demonstrated efficient, one-step insertion of pooled siRNA cassettes into entry vectors.
• Achieved seamless shotgun assembly of BstXI-digested SiEU fragments into the destination vector.
• Validated effective silencing of β-catenin and/or Smad4, inhibiting Wnt3A/BMP9 reporters and downstream targets in MSCs.
• Showed multiplex silencing diminished Wnt3A/BMP9-induced osteogenic differentiation.

Conclusions:

• The BSG system provides a user-friendly technology for single-vector multiplex siRNA expression.
• This system simplifies the study of gene functions and the development of experimental therapeutics.
• BSG enables efficient manipulation of gene expression for biological research and potential therapeutic applications.