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Advanced DNA structures, such as the G‐quadruplex (G4) and the i‐motif, are widely but not randomly present in the genomes of many organisms. A G4 structure was identified in the promoter of the silk gland factor‐1 gene (SGF1), which is the main regulatory gene for silk production in Bombyx mori. In this study, a BmSGF1 G4−/− homozygous mutant was generated with the G4 sequence knocked out. The promoter activity of BmSGF1 was lowered in the BmSGF1 G4−/− mutant. Pyridostatin (PDS) stabilized the G4 structure and increased the promoter activity of BmSGF1, whereas anti‐sense oligonucleotide (ASO) complementary to the G4 sequence suppressed the promoter activity of BmSGF1. Compared with wild‐type larvae, the deletion of the BmSGF1 G4 structure decreased both the expression of BmSGF1 and the fibroin heavy chain gene BmFib‐H in the posterior silk gland and the weight of the cocoons. Overall, these results suggest that the promoter G4 structure of BmSGF1 participates in the transcription regulation of the BmSGF1 gene in the silkworm. [ABSTRACT FROM AUTHOR]

Introduction: In recent years, Laos, with its unique geographical advantages, has vigorously developed overseas trade and cultural tourism industry, which has promoted local economic development and introduced numerous ecological and environmental problems.Method: Therefore, this research took Savan District as the research area, built the landscape ecological risk assessment model to reveal the spatiotemporal evolution characteristics of Savan District’s ecological risk from 2000 to 2020. Then, the Geodetector model was utilized to explain the driving forces behind changes in the landscape’s ecological risk. Finally, the Markov-PLUS coupling model was used to simulate and predict the changes in the land use pattern and ecological risk in the Savan District in 2030.Results: The following results are presented. 1) The landscape types in Savan District are mainly cultivated land and forest land, with the lowest degree of landscape fragmentation and loss, and the highest degree of landscape loss in unused land. 2) From 2000 to 2020, the average ecological risk index of the whole study area was low and showed a decreasing trend yearly, with the area of low-risk areas accounting for more than 90%. 3) In 2030, the average ecological risk index of the entire Savan District and the two provinces will rise, meanwhile the low-risk areas in the midwest regions and high-risk areas in the northwest will increase.Discussion: This study can guide the future coordinated development of the social economy and ecological environment in Savan District, Laos, and has good reference significance for ecological construction in similar areas in Southeast Asia.

Inspired by the human brain's capacity as a powerful biological computer capable of simultaneously processing a vast array of cognitive tasks, many emerging artificial synapse devices have been developed in recent years. Electric-double-layer (EDL) transistors based on interfacial ion-modulation have attracted widespread attention for simulating synaptic plasticity and neural functions. Here, low-voltage EDL p-type thin-film transistors (TFTs) are fabricated on glass substrates, with Ni-doped cuprous iodide (Ni0.06Cu0.94I) as the channel and chitosan as the dielectric. The electrical performance of the Ni0.06Cu0.94I TFTs is investigated: current on/off ratio of 6.4 × 104, subthreshold swing of 33 mV/dec, threshold voltage of 1.38 V, operating voltage of 2 V, and saturation field-effect mobility of 15.75 cm2 V−1 s−1. A dual in-plane gate OR logic operation is demonstrated. Importantly, by applying single voltage pulses, dual voltage pulses, and multiple voltage pulses to the gate, the Ni0.06Cu0.94I transistors exhibited typical synaptic characteristics, including short-term potentiation, short-term depression, long-term potentiation, long-term depression, paired-pulse facilitation, and spiking-rate-dependent plasticity. Furthermore, the synaptic transistor can also simulate the learning–forgetting–relearning process of the human brain. These remarkable behaviors of voltage-stimulated synaptic transistors have potential for neuromorphic applications in future artificial systems. [ABSTRACT FROM AUTHOR]

In this article, SnxCu1−xI thin-film transistors were fabricated on a glass substrate, with CuI doped with varying concentrations of SnI2 serving as the channel and chitosan as the dielectric. When x = 0.06, the device exhibited optimal performance: a current on/off ratio of 2.56 × 105, a subthreshold slope of 31.67 mV/dec, a threshold voltage of 1.33 V, and a saturated field-effect mobility of 21.75 cm2 V−1 s−1. Due to the electric double layer effect of chitosan, the operating voltage of the devices was reduced to below 2 V. Simulations were also conducted on the behavior and functionality of artificial synapses, such as short-term plasticity, long-term plasticity, and paired-pulse facilitation. Building upon the functionalities of artificial synapses, the Sn0.06Cu0.94I neuromorphic transistors simulated the fundamental pain perception function of biological nociceptors. Finally, the effects of bias stress and laser irradiation on the devices were investigated, indicating the excellent stability of the Sn0.06Cu0.94I neuromorphic transistors. Fabricated via the solution process, this low-voltage neuromorphic transistors hold significant implications for applications in bionic sensing systems and neuromorphic chip technology. [ABSTRACT FROM AUTHOR]

Insect cuticle is an apical extracellular matrix produced by the epidermis, tracheal, hind‐ and foregut epithelia during embryogenesis and renewed during molting and metamorphosis. However, the underlying regulatory mechanism for embryonic cuticle formation remains largely unclear. Here, we investigate the function of the transcription factor POUM2 in the embryonic cuticular formation in Bombyx mori, a model lepidopteran insect. Clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR‐associated protein‐9‐mediated knockout of POUM2 resulted in the defect of cuticular deposition, pigmentation, and sclerotization in the embryos. Differentially expressed transcripts analysis of 7‐d‐old embryos identified 174 up‐ or downregulated cuticular protein transcripts, 8 upregulated chitin degradation transcripts, 2 downregulated chitin synthesis transcripts and 48 up‐ or downregulated transcription factor transcripts in the POUM2−/− embryos. The expression levels of the key factors of the tyrosine metabolic pathway, such as tyrosine hydroxylase (Th), Dopa decarboxylase (DDC), and arylalkylamine N‐acetyltransferase (aaNAT), were significantly decreased in the POUM2−/− embryos. POUM2 isoform POUM2‐L specifically bound the POU cis‐regulatory element (CRE) in the Th promoter and increased the transcription of Th, whereas POUM2‐S could not bind the POU CRE, although it also increased the transcription of Th. Heterogeneous nuclear ribonucleoprotein Squid‐1 directly bound the POUM2 pre‐mRNA (messenger RNA) and inhibited the alternative splicing of POUM2‐L to POUM2‐S mRNA. These results suggest that POUM2 participates in the cuticular formation by regulating the chitin and cuticular protein synthesis and metabolism, and the cuticular pigmentation and sclerotization by regulating tyrosine metabolism during embryogenesis. This study provides new insights into novel function of POUM2 in embryogenesis. [ABSTRACT FROM AUTHOR]

Global increase of life expectancy is rarely accompanied by increased health span, calling for a greater understanding of age-associated behavioral decline. Motor independence is strongly associated with the quality of life of elderly people, yet the regulators for motor aging have not been systematically explored. Here, we designed a fast and efficient genome-wide screening assay in Caenorhabditis elegans and identified 34 consistent genes as potential regulators of motor aging. Among the top hits, we found VPS-34, the class III phosphatidylinositol 3-kinase that phosphorylates phosphatidylinositol (PI) to phosphatidylinositol 3-phosphate (PI(3)P), regulates motor function in aged but not young worms. It primarily functions in aged motor neurons by inhibiting PI(3)P-PI-PI(4)P conversion to reduce neurotransmission at the neuromuscular junction (NMJ). Genetic and pharmacological inhibition of VPS-34 improve neurotransmission and muscle integrity, ameliorating motor aging in both worms and mice. Thus, our genome-wide screening revealed an evolutionarily conserved, actionable target to delay motor aging and prolong health span. A genome-wide screen in the nematode Caenorhabditis elegans reveals potential targets to delay motor aging, including the phosphatidylinositol 3-kinase VPS-34. Genetic and pharmacological partial inhibition of VPS-34 improves neurotransmission and muscle integrity through increased PI(3)P-PI-PI(4)P conversion, ameliorating motor aging in both worms and mice. [ABSTRACT FROM AUTHOR]

It has been found that the non‐B form DNA structures, like G‐quadruplex (G4) and i‐motif, are involved in many important biological processes. Our previous study showed that the silkworm transcription factor BmLARK binds to the G4 structure in the promoter of the transcription factor BmPOUM2 and regulates its promoter activity. However, the binding mechanism between BmLARK and BmPOUM2 G4 structure remains unclear. In this study, binding domains and key amino acid residues involved in the interaction between BmLARK and BmPOUM2 G4 were studied. The electrophoretic mobility shift assay results indicated that the two RNA‐recognition motifs (RRM) of BmLARK are simultaneously required for the binding with the G4 structure. Either RRM1 or RRM2 alone could not bind with the G4 structure. The zinc‐finger motif was not involved in the binding. A series of mutant proteins with specific amino acid mutations were expressed and used to identify the key amino acid residues involving the interaction. The results indicated that β sheets, especially the β1 and β3 sheets, in the RRM domains of BmLARK played critical roles in the binding with the G4 structure. Several amino acid mutations of RRM1/2 in ribonucleoprotein domain 1 (RNP1) (motif in β3 strand) and RNP2 (motif in β1 strand) caused loss of binding ability, indicating that these amino acids are the key sites for the binding. All the results suggest that RRM domains, particularly their the RNP1 and RNP2 motifs, play important roles not only in RNA recognition, but also in the G4 structure binding. [ABSTRACT FROM AUTHOR]