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Purpose: Excessive application of chemical fertilizer leads to the problems of low yield and poor quality of potatoes in semi-arid areas. Therefore, the present study aimed to improve potato productivity in a semi-arid region by the partial substitution of organic fertilizers for chemical fertilizers. Methods: The field trial was conducted to study the effects of different fertilizer treatments (CK1, no fertilization; CK2, urea 450 kg·ha−1, calcium superphosphate 375 kg·ha−1, potassium sulphate 525 kg·ha−1(100% chemical fertilization); T1, 80% chemical fertilization + 3000 kg·ha −1organic fertilization; T2, 80% chemical fertilization + 6000 kg·ha −1organic fertilization; T3, 70% chemical fertilization + 3000 kg·ha −1organic fertilization; and T4, 70% chemical fertilization + 6000 kg·ha −1organic fertilization) on agronomic traits, photosynthetic characteristics, yield, and quality of potato. Results: The findings showed that T2 significantly increased the plant height, stem thickness, and soil–plant analysis development (SPAD) value of potatoes. The net photosynthetic rate (Pn), stomatal conductance (Gs), and transpiration rate (Tr) of T2 were significantly higher than that of the other treatments at the tuber expansion stage. In addition, higher yield, larger tubers, higher number of potatoes set per plant, and higher fertilizer contribution rate were found in T2 compared to other treatments. In T2, the yield reached 36,580 kg·ha−1and 37,915 kg·ha−1in 2018 and 2019, respectively. T2 significantly increased the contents of starch, vitamin C, and soluble protein in tubers but reduced the range of reducing sugar and nitrate compared to CK1 and CK2. Conclusions: Thus, the application of 80% chemical fertilization + 6000 kg·ha−1organic fertilization remarkably enhanced most agronomic and photosynthetic traits, which in turn improves potato growth, yield, and tuber quality, suggesting that 80% chemical fertilization + 6000 kg·ha−1organic fertilization can be used as a reasonable fertilizer application pattern in semi-arid areas. Graphical abstract:

DNA nanotechnology is beginning to yield unique advantages in the area of drug delivery. For the dual-targeting and proliferation suppression of cancer cells, a “willow branch” DNA assembly based on rolling circle amplification (RCA) was built. Three single-stranded DNAs, including antibody modified cDNAs, aptamer cDNAs, and simple cDNAs, were employed in the DNA self-assembly, along with the RCA scaffolds (every 63 bases is a repeat unit). “Willow branch” DNA (WB DNA) assembly successfully linked multiple antibodies and aptamers together to achieve dual targeting of cancer cells. Binding of CD44 antibodies and S2.2 aptamers to receptors on the cell membrane inhibits both pathways, β-catenin signaling and nuclear factor-kappa B-specific transcription activity, through feedback regulation. Results demonstrated that WB DNA assembly could effectively exert multivalency clustering cell-surface receptors, modulating signal pathways and inhibiting proliferation. This study proposes a new approach for cancer dual-target and proliferation inhibition by clustering multivalent receptors.

The manufacture of large-scale and highly ordered fluorescent assemblies has received more and more scientific attention in recent years. An ingenious and low-cost strategy for constructing large-scale DNA nanoarrays by rolling circle amplification (RCA) and a simplified DNA origami technique is proposed in this study. Thrombins are used to trigger the excitation of the fluorescent groups modified on the aptamer staple strands of nanoladders, which leads to the delicate construction of millimeter large-scale fluorescent nanoarrays, whose fluorescence intensity could be effectively regulated by the concentration of thrombin. The above fluorescent nanoarrays will generate a potential application value in the fields of biosensors, super-resolution imaging, and novel light-emitting devices.

The GPS-Nanoconveyor (MA-NV@DOX-Cas13a) is a targeted nanoplatform designed for the imaging and gene/chemotherapy synergistic treatment of melanoma. It utilizes rolling circle amplification (RCA) products as a scaffold to construct a DNA “Nanoconveyor” (NV), which incorporates a multivalent aptamer (MA) as a “GPS”, encapsulates doxorubicin (DOX) in the transporter, and equips it with CRISPR/Cas13a ribonucleoproteins (Cas13a RNP). Carrying MA enhances the ability to recognize the overexpressed receptor nucleolin on B16 cells, enabling targeted imaging and precise delivery of MA-NV@DOX-Cas13a through receptor-mediated endocytosis. The activation of signal transducer and activator of transcription 3 (STAT3) in cancer cells triggers cis-cleavage of CRISPR/Cas13a, initiating its trans-cleavage function. Additionally, deoxyribonuclease I (DNase I) degrades MA-NV, releasing DOX for intracellular imaging and as a chemotherapeutic agent. Experiments demonstrate the superior capabilities of this versatile nanoplatform for cellular imaging and co-treatment while highlighting the advantages of these nanodrug delivery systems in mitigating DOX side effects.

Combining the killing ability of chemotherapy drugs on tumor cells with the inhibiting ability of genetic drugs on tumor cell growth, a dual drug delivery system loaded with therapy drugs and siRNA has gradually received more and more research and extensive attention. In this paper, we designed a DNA nano-assembly based on rolling circle amplification that can co-deliver doxorubicin (Dox) and siRNA simultaneously. In order to fully exploit the potential of the dual loading system in cancer treatment, we selected STAT3 gene as a target and used siRNA to target STAT3 of mRNA and reduce the STAT3 expression in mouse melanoma cell line (B16); meanwhile, Dox as a chemotherapy drug was combined with multivalent aptamers specifically targeting B16 to achieve efficient delivery of siRNA and Dox. The results showed that the synergistic delivery system could achieve high efficiency in targeting and inhibiting proliferation in mouse melanoma cells. In addition, the synergistic effect of the dual delivery system on apoptosis of cancer cells was significantly better than that of single drug delivery systems.