Nucleic Acids Delivery Into the Cells Using Pro-Apoptotic Protein Lactaptin

Area of Science:

• Biochemistry
• Molecular Biology
• Biotechnology

Background:

• Cell-penetrating peptides (CPPs) are vital for intracellular delivery.
• Lactaptin, a kappa-casein fragment, and its recombinant form (RL2) induce cancer cell apoptosis.
• RL2's potential as a gene delivery system requires investigation.

Purpose of the Study:

• To evaluate recombinant lactaptin's (RL2) capacity to complex with nucleic acids.
• To assess RL2's efficacy as a gene delivery vehicle for plasmid DNA, siRNA, and non-coding RNA.
• To confirm intracellular delivery and functional activity of nucleic acids mediated by RL2.

Main Methods:

• RL2 complex formation with plasmid DNA (pDNA), siRNA, and U25 small nucleolar RNA (snoRNA) was analyzed.
• Complex size and stability were assessed, including the role of Ca2+ ions and heparin.
• Functional delivery was confirmed in A549 and A431 cancer cells using EGFP expression, siRNA-mediated gene silencing, and cell viability assays.

Main Results:

• RL2 formed stable, positively charged 110-nm complexes with pDNA, stabilized by Ca2+.
• RL2:pDNA complexes successfully delivered pDNA, leading to EGFP expression in cancer cells.
• RL2-mediated delivery of siRNA against EGFP inhibited EGFP expression, and RL2-snoRNA U25 complexes reduced cancer cell viability.

Conclusions:

• Recombinant lactaptin (RL2) effectively forms complexes with various nucleic acids.
• RL2 serves as an efficient non-viral gene delivery system for pDNA, siRNA, and snoRNA in cancer cells.
• RL2 demonstrates significant potential for targeted gene therapy applications in oncology.