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The generalized Lanczos algorithm can provide a universal method for constructing a wave function under the the Hamiltonian group structure. Based on this fact, we obtain an open two-mode squeezed state as the quantum origin for the curvature perturbation. In light of this wave function in the open system, we successfully develop a new method to calculate its corresponding power spectrum by using the Bogoliubov transformation. Unlike traditional approaches, we explicitly retain the Bogoliubov coefficients in terms of the squeezing amplitude r k and the squeezing rotation angle ϕ k . As a result, the power spectrum of the open two-mode squeezed state will match that of the Bunch–Davies vacuum numerically. Furthermore, the derivation of the open two-mode squeezed state relies on a Meixner polynomial of the second kind (equivalent to the generalized Lanczos algorithm) and the symmetry of the Hamiltonian. Therefore, our research may offer a new insight into the calculation of correlation functions through a group-theoretic perspective.

Significance We communicate the rather remarkable observation that among 291 tested accessions of cultivated sweet potato, all contain one or more transfer DNA (T-DNA) sequences. These sequences, which are shown to be expressed in a cultivated sweet potato clone (“Huachano”) that was analyzed in detail, suggest that an Agrobacterium infection occurred in evolutionary times. One of the T-DNAs is apparently present in all cultivated sweet potato clones, but not in the crop’s closely related wild relatives, suggesting the T-DNA provided a trait or traits that were selected for during domestication. This finding draws attention to the importance of plant–microbe interactions, and given that this crop has been eaten for millennia, it may change the paradigm governing the “unnatural” status of transgenic crops. Agrobacterium rhizogenes and Agrobacterium tumefaciens are plant pathogenic bacteria capable of transferring DNA fragments [transfer DNA (T-DNA)] bearing functional genes into the host plant genome. This naturally occurring mechanism has been adapted by plant biotechnologists to develop genetically modified crops that today are grown on more than 10% of the world’s arable land, although their use can result in considerable controversy. While assembling small interfering RNAs, or siRNAs, of sweet potato plants for metagenomic analysis, sequences homologous to T-DNA sequences from Agrobacterium spp. were discovered. Simple and quantitative PCR, Southern blotting, genome walking, and bacterial artificial chromosome library screening and sequencing unambiguously demonstrated that two different T-DNA regions ( Ib T-DNA1 and Ib T-DNA2) are present in the cultivated sweet potato ( Ipomoea batatas [L.] Lam.) genome and that these foreign genes are expressed at detectable levels in different tissues of the sweet potato plant. Ib T-DNA1 was found to contain four open reading frames (ORFs) homologous to the tryptophan-2-monooxygenase ( iaaM ), indole-3-acetamide hydrolase ( iaaH ), C-protein ( C-prot ), and agrocinopine synthase ( Acs ) genes of Agrobacterium spp. Ib T-DNA1 was detected in all 291 cultigens examined, but not in close wild relatives. Ib T-DNA2 contained at least five ORFs with significant homology to the ORF14 , ORF17n , rooting locus ( Rol ) B/RolC , ORF13 , and ORF18/ORF17n genes of A. rhizogenes . Ib T-DNA2 was detected in 45 of 217 genotypes that included both cultivated and wild species. Our finding, that sweet potato is naturally transgenic while being a widely and traditionally consumed food crop, could affect the current consumer distrust of the safety of transgenic food crops.

• Soil salinity and drought limit sweet potato yield. Scavenging of reactive oxygen species (ROS) by peroxidases (PRXs) is essential during plant stress responses, but how PRX expression is regulated under abiotic stress is not well understood. • Here, we report that the B-box (BBX) family transcription factor IbBBX24 activates the expression of the class III peroxidase gene IbPRX17 by binding to its promoter. Overexpression of IbBBX24 and IbPRX17 significantly improved the tolerance of sweet potato to salt and drought stresses, whereas reducing IbBBX24 expression increased their susceptibility. Under abiotic stress, IbBBX24- and IbPRX17-overexpression lines showed higher peroxidase activity and lower H₂O₂ accumulation compared with the wild-type. RNA sequencing analysis revealed that IbBBX24 modulates the expression of genes encoding ROS scavenging enzymes, including PRXs. • Moreover, interaction between IbBBX24 and the APETALA2 (AP2) protein IbTOE3 enhances the ability of IbBBX24 to activate IbPRX17 transcription. Overexpression of IbTOE3 improved the tolerance of tobacco plants to salt and drought stresses by scavenging ROS. • Together, our findings elucidate the mechanism underlying the IbBBX24–IbTOE3–IbPRX17 module in response to abiotic stress in sweet potato and identify candidate genes for developing elite crop varieties with enhanced abiotic stress tolerance.

Auxin response factors (ARFs) compose a family of transcription factors and have been found to play major roles in the process of plant growth and development. However, their roles in plant carotenoid biosynthesis and responses to abiotic stresses are rarely known to date. In the present study, we found that the gene from sweetpotato ( (L.) Lam.) line HVB-3 increased the contents of carotenoids and enhanced the tolerance to salt and drought in transgenic . The transgenic plants exhibited the increased abscisic acid (ABA) and proline contents and superoxide dismutase (SOD) activity and the decreased H O content. Furthermore, it was found that positively regulated the genes associated with carotenoid and ABA biosynthesis and abiotic stress responses. These results suggest that is involved in carotenoid biosynthesis and salt and drought tolerance in transgenic . This study provides a novel gene for improving carotenoid contents and salt and drought tolerance of sweetpotato and other plants.

[...]MWA needed a fewer number of ablation sessions and application puncture, which contributed to less invasion and costs. [...]with MWA, it was possible to decrease the time required for ablation by 60%, which provided patients unable to tolerate intravenous anaesthesia due to comorbidities a chance to undergo treatment.

WRKYs play important roles in plant growth, defense regulation, and stress response. However, the mechanisms through which WRKYs are involved in drought and salt tolerance have been rarely characterized in sweetpotato [Ipomoea batatas (L.) Lam.]. In this study, we cloned a WRKY gene, IbWRKY2, from sweetpotato and its expression was induced with PEG6000, NaCl, and abscisic acid (ABA). The IbWRKY2 was localized in the nucleus. The full-length protein exhibited transactivation activity, and its active domain was located in the N-terminal region. IbWRKY2-overexpressing Arabidopsis showed enhanced drought and salt tolerance. After drought and salt treatments, the contents of ABA and proline as well as the activity of superoxide dismutase (SOD) were higher in transgenic plants, while the malondialdehyde (MDA) and H2O2 contents were lower. In addition, several genes related to the ABA signaling pathway, proline biosynthesis, and the reactive oxygen species (ROS)-scavenging system, were significantly up-regulated in transgenic lines. These results demonstrate that IbWRKY2 confers drought and salt tolerance in Arabidopsis. Furthermore, IbWRKY2 was able to interact with IbVQ4, and the expression of IbVQ4 was induced by drought and salt treatments. These results provide clues regarding the mechanism by which IbWRKY2 contributes to the regulation of abiotic stress tolerance.

Efficient enzymatic conversion of crystalline polysaccharides is crucial for an economically and environmentally sustainable bioeconomy but remains unfavorably inefficient. We describe an enzyme that acts on the surface of crystalline chitin, where it introduces chain breaks and generates oxidized chain ends, thus promoting further degradation by chitinases. This enzymatic activity was discovered and further characterized by using mass spectrometry and chromatographic separation methods to detect oxidized products generated in the absence or presence of H₂¹⁸O or ¹⁸O₂. There are strong indications that similar enzymes exist that work on cellulose. Our findings not only demonstrate the existence of a hitherto unknown enzyme activity but also provide new avenues toward more efficient enzymatic conversion of biomass.

Sweet potato starch is in high demand globally for food and industry. However, starch content is negatively correlated with fresh yield. It is urgent to uncover the genetic basis and molecular mechanisms underlying the starch yield of sweet potato. Here we systematically explore source-sink synergy-mediated sweet potato starch yield formation: the production, loading, and transport of photosynthates in leaves, as well as their unloading and allocation in storage roots, lead to starch content divergence between sweet potato varieties. Moreover, we find that six haplotypes of IbPMA1 encoding a plasma membrane H + -ATPase are significantly linked with starch accumulation. Overexpression of IbPMA1 in sweet potato results in significantly increased starch and sucrose contents, while its knockdown exhibits an opposing effect. Furthermore, a basic helix-loop-helix (bHLH) transcription factor IbbHLH49 directly targets IbPMA1 and activates its transcription. Overexpression of IbbHLH49 notably improves source-sink synergy-mediated fresh yield and starch accumulation in sweet potato. Both IbbHLH49 and IbPMA1 substantially influence sugar transport and starch biosynthesis in source and sink tissues. These findings expand our understanding of starch yield formation and provide strategies and candidate genes for high starch breeding in root and tuber crops. Sweet potato starch has high global demand. Here the authors investigate the relationship between fresh yield and starch accumulation mediated by the source-sink process, and demonstrate that IbbHLH49 and IbPMA1 are vital for sugar transport and starch biosynthesis in sweet potato.

Soybean flowering and maturation are strictly regulated by photoperiod. Photoperiodsensitive soybean varieties can undergo flowering reversion when switched from short-day (SD) to long-day (LD) conditions, suggesting the presence of a ‘floral-inhibitor’ under LD conditions. We combined gene expression profiling with a study of transgenic plants and confirmed that GmFT1a, soybean Flowering Locus T (FT) homolog, is a floral inhibitor. GmFT1a is expressed specifically in leaves, similar to the flowering-promoting FT homologs GmFT2a/5a. However, in Zigongdongdou (ZGDD), a model variety for studying flowering reversion, GmFT1a expression was induced by LD but inhibited by SD conditions. This was unexpected, as it is the complete opposite of the expression of flowering promoters GmFT2a/5a. Moreover, the key soybean maturity gene E1 may up-regulate GmFT1a expression. It is also notable that GmFT1a expression was conspicuously high in late-flowering varieties. Transgenic overexpression of GmFT1a delayed flowering and maturation in soybean, confirming that GmFT1a functions as a flowering inhibitor. This discovery highlights the complex impacts of the functional diversification of the FT gene family in soybean, and implies that antagonism between flowering-inhibiting and flowering-promoting FT homologs in this highly photoperiod-sensitive plant may specify vegetative vs reproductive development.

A novel colorimetric and ratiometric fluorescence sensor was constructed by using carbon quantum dots (CQDs) and o-diaminobenzene (ODB). Unlike ODB by itself, ODB oxide (oxODB) not only emits fluorescence, but also produces ultraviolet (UV) absorption. Therefore, on the basis of the potential optical properties of ODB, glucose oxidase (Gox) and horseradish peroxidase (HRP) were introduced into a CQDs–ODB system for the quantitative oxidation of ODB. When glucose is present, it is oxidized by oxygen under the catalytic action of its oxidase to form hydrogen peroxide. Hydrogen peroxide is a strong oxidant that can rapidly oxidize ODB through the catalysis of horseradish peroxidase. oxODB can cause changes in the fluorescence ratio (I550/I446) and absorbance ratio (A/A0). At the same time, the color of the detection solution can also change under sunlight and ultraviolet lamps. Therefore, glucose can be quantitatively detected by ratiometric fluorescence and colorimetry simultaneously, and semi-quantitatively detected by observing the colors with sunlight and ultraviolet lamps of 365 nm. This increases not only the convenience but also the accuracy of detection. In addition, this sensor has good selectivity and can be used for the determination of glucose in serum, providing a new idea for the development of blood glucose sensors.