Multiple independent origins of the female W chromosome in moths and butterflies.

Lepidoptera, the most diverse group of insects, exhibit female heterogamy (Z0 or ZW), which is different from most other insects (male heterogamy, XY). Previous studies suggest a single origin of the Z chromosome. However, the origin of the lepidopteran W chromosome remains poorly understood. Here, we assemble the genome from females down to the chromosome level of a model insect (Bombyx mori) and identify a W chromosome of approximately 10.1 megabase using a newly developed tool. In addition, we identify 3593 genes that were not previously annotated in the genomes of B. mori. Comparisons of 21 lepidopteran species (including 17 ZW and four Z0 systems) and three trichopteran species (Z0 system) reveal that the formation of Ditrysia W involves multiple mechanisms, including previously proposed canonical and noncanonical models, as well as a newly proposed mechanism called single-Z turnover. We conclude that there are multiple independent origins of the W chromosome in the Ditrysia (most moths and all butterflies) of Lepidoptera.

Surface hydrophobization of zeolite enables mass transfer matching in gas-liquid-solid three-phase hydrogenation under ambient pressure.

Attaining high hydrogenation performance under mild conditions, especially at ambient pressure, remains a considerable challenge due to the difficulty in achieving efficient mass transfer at the gas-liquid-solid three-phase interface. Here, we present a zeolite nanoreactor with joint gas-solid-liquid interfaces for boosting H2 gas and substrates to involve reactions. Specifically, the Pt active sites are encapsulated within zeolite crystals, followed by modifying the external zeolite surface with organosilanes. The silane sheath with aerophilic/hydrophobic properties can promote the diffusion of H2 and the mass transfer of reactant/product molecules. In aqueous solutions, the gaseous H2 molecules can rapidly diffuse into the zeolite channels, thereby augmenting H2 concentration surround Pt sites. Simultaneously, the silane sheath with lipophilicity nature promotes the enrichment of the aldehydes/ketones on the catalyst and facilitates the hydrophilia products of alcohol rediffusion back to the aqueous phase. By modifying the wettability of the catalyst, the hydrogenation of aldehydes/ketones can be operated in water at ambient H2 pressure, resulting in a noteworthy turnover frequency up to 92.3 h-1 and a 4.3-fold increase in reaction rate compared to the unmodified catalyst.

Yiqi Jiedu Xiaoying Decoction Improves Experimental Autoimmune Thyroiditis in Rats by Regulating Th17/Treg Cell Balance.

BACKGROUND: Experimental autoimmune thyroiditis (EAT) is a widely used animal model to study the pathogenesis and treatment of autoimmune thyroid diseases. Yiqi Jiedu Xiaoying Decoction (YJXD) is a traditional Chinese medicine formula with potential immunomodulatory effects. In this study, we investigated the therapeutic effects of YJXD on EAT in rats and explored its underlying mechanisms. METHODS: Female Wistar rats were induced to develop EAT by immunization with thyroglobulin (Tg) and taken sodium iodide water (0.05%) and then treated with YJXD or sodium selenite. HE staining was used to observe the pathological changes of thyroid tissue in EAT rats. Th17 and Treg cell frequencies were analyzed by flow cytometry, and the expression levels of Th17- and Treg-related cytokines and thyroid autoantibody were determined by enzyme-linked immunosorbent assay (ELISA). The expression of Th17- and Treg-related transcriptional factors was detected by real-time polymerase chain reaction (RT-PCR) and Immunohistochemistry (IHC). RESULTS: Our results demonstrated that treatment with YJXD significantly attenuated the severity of EAT, as evidenced by reduced thyroid gland inflammatory infiltration and decreased serum thyroglobulin autoantibody levels. Importantly, YJXD treatment effectively modulated the Th17/Treg cell balance by suppressing Th17 cell differentiation and promoting Treg cell expansion. Moreover, YJXD was also found to regulate the expression levels of Th17- and Tregrelated cytokines and transcriptional factors, further supporting its immunomodulatory effects in EAT. CONCLUSION: YJXD exerted therapeutic effects on EAT by regulating the Th17/Treg cell balance, modulating the production of Th17- and Treg-related cytokines and the expression of transcriptional factors.

Multidimensional Widefield Infrared-Encoded Spontaneous Emission Microscopy: Distinguishing Chromophores by Ultrashort Infrared Pulses.

Photoluminescence (PL) imaging has broad applications in visualizing biological activities, detecting chemical species, and characterizing materials. However, the chemical information encoded in the PL images is often limited by the overlapping emission spectra of chromophores. Here, we report a PL microscopy based on the nonlinear interactions between mid-infrared and visible excitations on matters, which we termed MultiDimensional Widefield Infrared-encoded Spontaneous Emission (MD-WISE) microscopy. MD-WISE microscopy can distinguish chromophores that possess nearly identical emission spectra via conditions in a multidimensional space formed by three independent variables: the temporal delay between the infrared and the visible pulses (t), the wavelength of visible pulses (λvis), and the frequencies of the infrared pulses (ωIR). This method is enabled by two mechanisms: (1) modulating the optical absorption cross sections of molecular dyes by exciting specific vibrational functional groups and (2) reducing the PL quantum yield of semiconductor nanocrystals, which was achieved through strong field ionization of excitons. Importantly, MD-WISE microscopy operates under widefield imaging conditions with a field of view of tens of microns, other than the confocal configuration adopted by most nonlinear optical microscopies, which require focusing the optical beams tightly. By demonstrating the capacity of registering multidimensional information into PL images, MD-WISE microscopy has the potential of expanding the number of species and processes that can be simultaneously tracked in high-speed widefield imaging applications.

Mutation Rate and Spectrum of the Silkworm in Normal and Temperature Stress Conditions.

Mutation rate is a crucial parameter in evolutionary genetics. However, the mutation rate of most species as well as the extent to which the environment can alter the genome of multicellular organisms remain poorly understood. Here, we used parents-progeny sequencing to investigate the mutation rate and spectrum of the domestic silkworm (Bombyx mori) among normal and two temperature stress conditions (32 °C and 0 °C). The rate of single-nucleotide mutations in the normal temperature rearing condition was 0.41 × 10-8 (95% confidence interval, 0.33 × 10-8-0.49 × 10-8) per site per generation, which was up to 1.5-fold higher than in four previously studied insects. Moreover, the mutation rates of the silkworm under the stresses are significantly higher than in normal conditions. Furthermore, the mutation rate varies less in gene regions under normal and temperature stresses. Together, these findings expand the known diversity of the mutation rate among eukaryotes but also have implications for evolutionary analysis that assumes a constant mutation rate among species and environments.

The Landscapes of Full-Length Transcripts and Splice Isoforms as Well as Transposons Exonization in the Lepidopteran Model System, Bombyx mori.

The domesticated silkworm, Bombyx mori, is an important model system for the order Lepidoptera. Currently, based on third-generation sequencing, the chromosome-level genome of Bombyx mori has been released. However, its transcripts were mainly assembled by using short reads of second-generation sequencing and expressed sequence tags which cannot explain the transcript profile accurately. Here, we used PacBio Iso-Seq technology to investigate the transcripts from 45 developmental stages of Bombyx mori. We obtained 25,970 non-redundant high-quality consensus isoforms capturing ∼60% of previous reported RNAs, 15,431 (∼47%) novel transcripts, and identified 7,253 long non-coding RNA (lncRNA) with a large proportion of novel lncRNA (∼56%). In addition, we found that transposable elements (TEs) exonization account for 11,671 (∼45%) transcripts including 5,980 protein-coding transcripts (∼32%) and 5,691 lncRNAs (∼79%). Overall, our results expand the silkworm transcripts and have general implications to understand the interaction between TEs and their host genes. These transcripts resource will promote functional studies of genes and lncRNAs as well as TEs in the silkworm.

Filtration of submicron dust by a dual-layer granular bed filter with an external electric field.

To improve the filtration efficiency of submicron dust by dual-layer granular bed filters, filtration experiments for micro-silica powder were conducted for removing particles smaller than 1 µm that account for more than 96% (by volume) using a dual-layer granular bed filter with an external electric field. Electrostatic enhancement methods, including dust pre-charging, application of an electric field to the lower filter layer, and that to both the upper and lower filter layers, were examined. Results showed that the average filtration efficiency of a dual-layer granular bed filter for micro-silica powder without electric field was 76.52%, the average outlet dust concentration was 263.53 mg/m3, and the filtration cycle time was 73 min. With pre-charged dust, the average outlet dust concentration dropped to 82.51 mg/m3. A decrease in the thickness of the lower filter layer from 45 to 25 mm with electric field reduced the pressure drop from 2570 to 1770 Pa. Meanwhile, the application of an electric field to the lower/upper filter layer reduced the average outlet dust concentration to 25.98 mg/m3. Increasing the initial face velocity from 0.25 to 0.45 m/s increased the average outlet dust concentration from 25.98 to 30.27 mg/m3 and increased the pressure drop from 2570 to 3500 Pa.

Flight Muscle and Wing Mechanical Properties are Involved in Flightlessness of the Domestic Silkmoth, Bombyx mori.

Flight loss has occurred in many winged insect taxa. The flightless silkmoth Bombyx mori, is domesticated from the wild silkmoth, Bombyx mandarina, which can fly. In this paper, we studied morphological characteristics attributed to flightlessness in silkmoths. Three domestic flightless B. mori strains and one B. mandarina population were used to compare morphological components of the flight apparatus, including wing characteristics (shape, forewing area, loading, and stiffness), flight muscle (weight, ratio, and microscopic detail) and body mass. Compared with B. mandarina, B. mori strains have a larger body, greater wing loading, more flexible wings and a lower flight muscle ratio. The arrangement in microscopy of dorsal longitudinal flight muscles (DLFMs) of B. mori was irregular. Comparative analysis of the sexes suggests that degeneration of flight muscles and reduction of wing mechanical properties (stiffness) are associated with silkmoth flightlessness. The findings provide important clues for further research of the molecular mechanisms of B. mori flight loss.