title: In vitro and in vivo gene silencing by TransKingdom RNAi (tkRNAi).
abstract: RNA interference (RNAi) is a potent and specific mechanism for eliminating the mRNA of specific genes. This gene silencing mechanism occurs naturally and is highly conserved from plants to human cells, holding promise for functional genomics and for revolutionizing medicine due to its unlimited potential to treat genetic, epigenetic, and infectious disease. However, efforts to unleash the enormous potential of RNAi have met with significant challenges. Delivery is problematic because short interfering RNAs (siRNA) are negatively charged polymers that inefficiently enter cells and undergo rapid enzymatic degradation in vivo. In addition, the synthesis of siRNAs is expensive for long-term research and therapeutic applications. Recently, we have shown that nonpathogenic bacteria can be engineered to activate RNAi in mammalian cells (TransKingdom RNA interference; tkRNAi). This new approach offers several advantages and has significant implications. First, this method allows the establishment of a long-term stable gene silencing system in the laboratory against genes of interests in vitro and in vivo, and enables high-throughput functional genomics screening in mammalian systems. RNAi libraries can be constructed, stored, reproduced, amplified, and used with the help of E. coli as currently done with gene cloning. Second, this technology provides a clinically compatible way to achieve RNAi for therapeutic applications due to the proven clinical safety ofnonpathogenic bacteria as a gene carrier, tkRNAi also eliminates the siRNA manufacture issue, and may circumvent or mitigate host interferon-like responses since siRNA is produced intracellularly.
authors.affiliation: Skip Ackerman Center for Molecular Therapeutics, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Shuanglin
authors.initials: S
authors.lastname: Xiang
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Keates
authors.forename: Johannes
authors.initials: J
authors.lastname: Fruehauf
authors.forename: Youxin
authors.initials: Y
authors.lastname: Yang
authors.forename: Hongnian
authors.initials: H
authors.lastname: Guo
authors.forename: Thu
authors.initials: T
authors.lastname: Nguyen
authors.forename: Chiang J
authors.initials: CJ
authors.lastname: Li
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics / Q000628:therapy*; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D055785:Gene Knockdown Techniques / Q000379:methods*; D020868:Gene Silencing; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000235:genetics; D014183:Transplantation, Heterologous; D051176:beta Catenin / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism
chemical_list: D034741:RNA, Small Interfering; D051176:beta Catenin