Application of polymeric dimethylaminoethyl methacrylate based carriers of plasmid DNA for genetic transformation of Ceratodon purpureus moss

Introduction. Genetic engineering in plants is of great importance for agriculture, biotechnology and medicine, and nanomaterials are widely used for genetic engineering. The aim of present study was to evaluate the potential of poly(2-dimethylamino)ethyl methacrylate (DMAEMA)-based comb-like polymers as gene delivery systems in moss Ceratodon purpureus (Hedw.) Brid. protoplasts and determine the level of phytotoxicity of these polymers. Materials and Methods. In order to confirm the formation of complex of poly-DMAEMA carrier with plasmid DNA pSF3, gel retardation assay was used. The PEG-mediated transformation protocol was adapted to transform the protoplasts of C. purpureus moss with poly-DMAEMA carriers. Light microscopy was used to study a toxicity of polymers for moss protoplasts. The level of the polymers toxicity was estimated as IC50 value. Results and Discussion. The formation of pDNA complex with DMAEMA-based carriers took place at 0.03% concentration of the polymers BGA-21, BGA-22(2ph), BG-24, BG-25, BG-26 or 0.1% concentration of the BGA-22 polymer. Poly-DMAEMA carriers were able to deliver plasmid DNA pSF3 into protoplasts of C. purpureus moss. Three stable transformants of C. purpureus were obtained at using BGA-22 polymer, 2 clones – at using BGA-21 carrier, and 1 clone – at using BGA-22(2ph), BG-24, BG-25, BG-26 polymers. The poly-DMAEMA carriers at the working 0.0025% dose were relatively non-toxic for protoplasts of C. purpureus moss. 83.1-88.4% of viable protoplasts of C. purpureus moss were detected after treatment with studied carriers at 0.0025% dose. A survival ratio of protoplasts reached 66.7-72.9% under the effect of these polymers at 0.025% dose, which is 10 times higher than their working concentration. The IC50 value of poly-DMAEMA carriers was in the range of 0.113-0.164%, that was approximately 10 times higher than that of the PEG-6000 used for gene delivery in plants. Conclusion. Novel synthetic poly-DMAEMA carriers delivered the gene of interest into moss C. purpureus protoplasts and possessed a low phytotoxicity. Thus, these carriers can be useful for gene delivery into plant cells.

Insights into the Action Mechanism of the Antimicrobial Peptide Lasioglossin III

Lasioglossin III (LL-III) is a cationic antimicrobial peptide derived from the venom of the eusocial bee Lasioglossum laticeps. LL-III is extremely toxic to both Gram-positive and Gram-negative bacteria, and it exhibits antifungal as well as antitumor activity. Moreover, it shows low hemolytic activity, and it has almost no toxic effects on eukaryotic cells. However, the molecular basis of the LL-III mechanism of action is still unclear. In this study, we characterized by means of calorimetric (DSC) and spectroscopic (CD, fluorescence) techniques its interaction with liposomes composed of a mixture of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-rac-phosphoglycerol (POPG) lipids as a model of the negatively charged membrane of pathogens. For comparison, the interaction of LL-III with the uncharged POPC liposomes was also studied. Our data showed that LL-III preferentially interacted with anionic lipids in the POPC/POPG liposomes and induces the formation of lipid domains. Furthermore, the leakage experiments showed that the peptide could permeabilize the membrane. Interestingly, our DSC results showed that the peptide-membrane interaction occurs in a non-disruptive manner, indicating an intracellular targeting mode of action for this peptide. Consistent with this hypothesis, our gel-retardation assay experiments showed that LL-III could interact with plasmid DNA, suggesting a possible intracellular target.

Entrapment Formulation for env-Tm Gene Based on Chitosan Low Molecular Weight as a Jembrana Disease Virus Vaccine Candidate

Jembrana disease (JD) caused by Jembrana Disease Virus (JDV) becomes an obstacle in Bali cattle (Bos javanicus). The development of JD vaccines has a critical meaning to prevent losses in the B. javanicus in Indonesia and is one of the models in the development of the Human Immunodeficiency Virus (HIV) vaccine. The development of vaccines for JDV has carried out DNA vaccines that are expected to provide better immunological effects. This study aimed to determine the low molecular weight chitosan (LC) entrapment towards pEGFP-C1-env-Tm in the formation of Chitosan Nanoparticles Low/pEGFP-C1-env-Tm complex. The env-Tm gene was inserted in pEGFP-C1 into the pEGFPC1/ env-Tm construct transformed on the E. coli DH5α host. The construct was formulated into LC/pEGFP-C1/env-Tm complex with a low molecular weight chitosan concentration of 0.06 % and the ratio of pEGFP-C1/env-Tm: LC (wt/wt) was 1:0.5-1:3. The complexes were then analyzed by gel retardation assay agarose 1 %. The results of this study indicated that the best entrapment results of low molecular weight chitosan to pEGFPC1/ env-Tm was in the mass ratio of pEGFP-C1/env-Tm: LC was 1:2. The best formulation entrapment for env-Tm by low molecular weight chitosan 0.06 % is in the rate 1:2.

Polyglycerol-functionalized nanodiamond as a platform for gene delivery: Derivatization, characterization, and hybridization with DNA

A gene vector consisting of nanodiamond, polyglycerol, and basic polypeptide (ND-PG-BPP) has been designed, synthesized, and characterized. The ND-PG-BPP was synthesized by PG functionalization of ND through ring-opening polymerization of glycidol on the ND surface, multistep organic transformations (–OH → –OTs (tosylate) → –N3) in the PG layer, and click conjugation of the basic polypeptides (Arg8, Lys8 or His8) terminated with propargyl glycine. The ND-PG-BPP exhibited good dispersibility in water (>1.0 mg/mL) and positive zeta potential ranging from +14.2 mV to +44.1 mV at neutral pH in Milli-Q water. It was confirmed by gel retardation assay that ND-PG-Arg8 and ND-PG-Lys8 with higher zeta potential hybridized with plasmid DNA (pDNA) through electrostatic attraction, making them promising as nonviral vectors for gene delivery.

A Polyethylenimine-Linoleic Acid Conjugate for Antisense Oligonucleotide Delivery

A novel antisense oligonucleotide (ASO) carrier, polyethylenimine conjugated to linoleic acid (PEI-LA), was synthesized and evaluated for delivery of LOR-2501 to tumor cells. LOR-2501 is an ASO targeting ribonucleotide reductase R1 subunit (RRM1). In this study, PEI-LA was synthesized by reacting PEI (Mw ~ 800) with linoleoyl chloride. Gel retardation assay showed complete complexation between PEI-LA and LOR-2501 at N/P ratio above 8. No significant cytotoxicity was observed with these complexes at the tested dosage levels. Interestingly, at N/P ratio of >6, levels of cellular uptake of PEI-LA/LOR-2501 were double that of PEI/LOR-2501 complexes of the same N/P ratio. PEI-LA/LOR-2501 induced downregulation of 64% and 70% of RRM1 at mRNA and protein levels, respectively. The highest transfection activity was shown by PEI-LA/LOR-2501 complexes at N/P ratio of 10. Finally, using pathway specific inhibitors, clathrin-mediated endocytosis was shown to be the principle mechanism of cellular internalization of these complexes. In conclusion, PEI-LA is a promising agent for the delivery of ASOs and warrants further investigation.

Efficiency of Cationic Rosette Nanotubes for siRNA Delivery

ABSTRACTCationic rosette nanotubes (RNTs) were generated by functionalization of selfcomplementary twin guanine-cytosine (G^C) motifs with up to 15 L-lysine residues (Kn.T, n = 1–15). siRNA binding capacity was determined by gel retardation assay on agarose gel. Up to K5.T, siRNA complexation was a function of oligolysine-chain length and mole ratio of Kn.T. At higher Kn.T, local cationic density employed by supramolecular assembly emerged as a contributor to siRNA complexation. We have shown that no effective siRNA binding was achieved with equivalent mole ratios of corresponding oligolysine peptides (not conjugated to the G∧C motif). With K12.T, siRNA complexation gave spherical structures in the range of 200 nm, which was internalized and retained by human cell lines without noticeable cytotoxicity. In this report, we demonstrate for the first time the capacity of the RNTs as siRNA carriers that can be tailored to achieve maximum siRNA loading efficiency without carrier-associated cell toxicity. We anticipate these cationic RNTs to be effective in the delivery of biologicallyfunctional siRNA.