Reconstitution of RNA cap methylation reveals different features of SARS-CoV-2 and SARS-CoV methyltransferases.

Cap RNA methylations play important roles in the replication, evasion of host RNA sensor recognition, and pathogenesis. Coronaviruses possess both guanine N7- and 2'-O-ribose methyltransferases (N7-MTase and 2'-O-MTase) encoded by nonstructural protein (nsp) 14 and nsp16/10 complex, respectively. In this study, we reconstituted the two-step RNA methylations of N7-MTase and 2'-O-MTase of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro and demonstrated its common and different features in comparison with that of SARS-CoV. We revealed that the nsp16/10 2'-O-MTase of SARS-CoV-2 has a broader substrate selectivity than the counterpart of SARS-CoV and can accommodate both unmethylated and uncapped RNA substrates in a sequence-independent manner. Most intriguingly, the substrate selectivity of nsp16/10 complex is not determined by the apoenzyme of nsp16 MTase but by its cofactor nsp10. These results provide insight into the unique features of SARS-CoV-2 MTases and may help develop strategies to precisely intervene in the methylation pathway and pathogenesis of SARS-CoV-2.

Molecular phylogeny, historical biogeography, and classification of Pseudocoladenia butterflies (Lepidoptera: Hesperiidae).

The range of the butterfly genus Pseudocoladenia includes several biodiversity hotspots, such as the Himalayas, mountains of southwestern China, and Sundaland. However, the taxonomic status of some of its species/subspecies remain controversial, and no previous phylogenetic or biogeographic analyses have been conducted. Herein, we determined the systematic relationships and biogeographic history of this genus by reconstructing its phylogeny based on six genes and 69 specimens as representatives of all known species/subspecies. Two species delimitation methods (Bayes Poisson Tree Processes and Bayesian Phylogenetics and Phylogeography) were also employed to assess the status of each taxon. Based on these results and morphological evidence, we identified 12 species and three subspecies in the genus and subsequently classified these into three species groups: P. fatih, P. dea, and P. dan. Five taxa, P. sadakoe (Sonan and Mitono, 1936) stat. nov., P. celebica (Fruhstorfer, 1909) stat. nov., P. fulvescens (Elwes and Edwarda, 1897) stat. nov., P. eacus (Latreille, 1823) stat. nov., and P. fabia (Evans, 1949) stat. nov. were all recognized as independent species. Additionally, two taxa, P. eacus sumatrana (Fruhstorfer, 1909) comb. nov. and P. eacus dhyana (Fruhstorfer, 1909) comb. nov., were placed under P. eacus (Latreille, 1823) stat. nov. as subspecies. Another new species distributed in N. Yunnan, Pseudocoladenia yunnana Fan, Cao & Hou sp. nov., was discovered and described. Divergence time and ancestral range estimation indicated that the most recent common ancestor of Pseudocoladenia was distributed in the Himalayas-Hengduan Mountain region and Indochina and diverged approximately 14.00 Ma. Continuous and episodic dispersal, vicariance, and extinction were used to determine the current geographic distribution of the genus. The P. fatih group had a prominently disjunct distribution between the Himalaya-Hengduan Mountain and Taiwan. Meanwhile, the P. dan group was first derived in Indochina and subsequently dispersed into the southeastern Asian archipelagoes. This study provides a reference for the evolutionary route of transoceanic distributed species in Asia and elaborates on the causes of biodiversity.

Comparison of model-specific histopathology in mouse models of COVID-19.

A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been identified as the causative agent of the current coronavirus disease 2019 pandemic. Development of animal models that parallel the clinical and pathologic features of disease are highly essential to understanding the pathogenesis of SARS-CoV-2 infection and the development of therapeutics and prophylactics. Several mouse models that express the human angiotensin converting enzyme 2 (hACE2) have been created, including transgenic and knock-in strains, and viral vector-mediated delivery of hACE2. However, the comparative pathology of these mouse models infected with SARS-CoV-2 are unknown. Here, we perform systematic comparisons of the mouse models including K18-hACE2 mice, KI-hACE2 mice, Ad5-hACE2 mice and CAG-hACE2 mice, which revealed differences in the distribution of lesions and the characteristics of pneumonia induced. Based on these observations, the hACE2 mouse models meet different needs of SARS-CoV-2 researches. The similarities or differences among the model-specific pathologies may help in better understanding the pathogenic process of SARS-CoV-2 infection and aiding in the development of effective medications and prophylactic treatments for SARS-CoV-2.

A multilocus analysis of Epicopeiidae (Lepidoptera, Geometroidea) provides new insights into their relationships and the evolutionary history of mimicry.

The family Epicopeiidae is a small group of day-flying moths, known for mimicking many different groups of butterflies and moths. So far, there still lacks a reliable phylogenetic framework of Epicopeiidae that is necessary to our understanding of the evolutionary process of their mimicry. In this study, we sequenced 94 nuclear protein-coding markers for 56 epicopeiid samples and 11 outgroups, covering all ten genera of Epicopeiidae. We used homemade PCR-generated baits to capture target sequences, which allowed us to utilize old and dried specimens that were difficult to handle by conventional PCR + Sanger sequencing. Maximum likelihood and Bayesian analyses of the newly obtained dataset (86,388 bp) at both DNA and protein levels produced identical phylogenies with strong support. The non-mimicry genus Deuveia is the sister group of other epicopeiid genera. Epicopeia and Nossa are not monophyletic, and these two genera nest together to form a clade. We also estimated divergence times of Epicopeiidae and found that their initial diversification happened in Eocene about 41 million years ago. The ancestral state reconstruction of mimicry type for this family suggested that thelast common ancestor of epicopeiid moths is non-mimetic, and the Riodinidae-mimicry type evolved first. In summary, our work provides a comprehensive and robust time-calibrated phylogeny of Epicopeiidae that provides a sound framework for revising their classification and interpreting character evolution.

Regulating the Golgi apparatus sorting of proteinase A to decrease its excretion in Saccharomyces cerevisiae.

Beer foam stability, a key factor in evaluating overall beer quality, is influenced by proteinase A (PrA). Actin-severing protein cofilin and Golgi apparatus-localized Ca2+ ATPase Pmr1 are involved in protein sorting at the trans-Golgi network (TGN) in yeast Curwin et al. (Mol Biol Cell 23:2327-2338, 2012). To reduce PrA excretion into the beer fermentation broth, we regulated the Golgi apparatus sorting of PrA, thereby facilitating the delivery of more PrA to the vacuoles in the yeast cells. In the present study, the cofilin-coding gene COF1 and the Pmr1-coding gene PMR1 were overexpressed in the parental strain W303-1A and designated as W + COF1 and W + PMR1, respectively. The relative expression levels of COF1 in W + COF1 and PMR1 in W + PMR1 were 5.26- and 19.76-fold higher than those in the parental strain. After increases in the expression levels of cofilin and Pmr1 were confirmed, the PrA activities in the wort broth fermented with W + COF1, W + PMR1, and W303-1A were measured. Results showed that the extracellular PrA activities of W + COF1 and W + PMR1 were decreased by 9.24% and 13.83%, respectively, at the end of the main fermentation compared with that of W303-1A. Meanwhile, no apparent differences were found on the fermentation performance of recombinant and parental strains. The research uncovers an effective strategy for decreasing PrA excretion in Saccharomyces cerevisiae.

Heterologous expression of Spathaspora passalidarum xylose reductase and xylitol dehydrogenase genes improved xylose fermentation ability of Aureobasidium pullulans.

BACKGROUND: Aureobasidium pullulans is a yeast-like fungus that can ferment xylose to generate high-value-added products, such as pullulan, heavy oil, and melanin. The combinatorial expression of two xylose reductase (XR) genes and two xylitol dehydrogenase (XDH) genes from Spathaspora passalidarum and the heterologous expression of the Piromyces sp. xylose isomerase (XI) gene were induced in A. pullulans to increase the consumption capability of A. pullulans on xylose. RESULTS: The overexpression of XYL1.2 (encoding XR) and XYL2.2 (encoding XDH) was the most beneficial for xylose utilization, resulting in a 17.76% increase in consumed xylose compared with the parent strain, whereas the introduction of the Piromyces sp. XI pathway failed to enhance xylose utilization efficiency. Mutants with superior xylose fermentation performance exhibited increased intracellular reducing equivalents. The fermentation performance of all recombinant strains was not affected when glucose or sucrose was utilized as the carbon source. The strain with overexpression of XYL1.2 and XYL2.2 exhibited excellent fermentation performance with mimicked hydrolysate, and pullulan production increased by 97.72% compared with that of the parent strain. CONCLUSIONS: The present work indicates that the P4 mutant (using the XR/XDH pathway) with overexpressed XYL1.2 and XYL2.2 exhibited the best xylose fermentation performance. The P4 strain showed the highest intracellular reducing equivalents and XR and XDH activity, with consequently improved pullulan productivity and reduced melanin production. This valuable development in aerobic fermentation by the P4 strain may provide guidance for the biotransformation of xylose to high-value products by A. pullulans through genetic approach.

Discovering the role of the apolipoprotein gene and the genes in the putative pullulan biosynthesis pathway on the synthesis of pullulan, heavy oil and melanin in Aureobasidium pullulans.

Pullulan produced by Aureobasidium pullulans presents various applications in food manufacturing and pharmaceutical industry. However, the pullulan biosynthesis mechanism remains unclear. This work proposed a pathway suggesting that heavy oil and melanin may correlate with pullulan production. The effects of overexpression or deletion of genes encoding apolipoprotein, UDPG-pyrophosphorylase, glucosyltransferase, and α-phosphoglucose mutase on the production of pullulan, heavy oil, and melanin were examined. Pullulan production increased by 16.93 and 8.52% with the overexpression of UDPG-pyrophosphorylase and apolipoprotein genes, respectively. Nevertheless, the overexpression or deletion of other genes exerted little effect on pullulan biosynthesis. Heavy oil production increased by 146.30, 64.81, and 33.33% with the overexpression of UDPG-pyrophosphorylase, α-phosphoglucose mutase, and apolipoprotein genes, respectively. Furthermore, the syntheses of pullulan, heavy oil, and melanin can compete with one another. This work may provide new guidance to improve the production of pullulan, heavy oil, and melanin through genetic approach.

Prediction of matrix-to-cell stress transfer in heart valve tissues.

Non-linear and anisotropic heart valve leaflet tissue mechanics manifest principally from the stratification, orientation, and inhomogeneity of their collagenous microstructures. Disturbance of the native collagen fiber network has clear consequences for valve and leaflet tissue mechanics and presumably, by virtue of their intimate embedment, on the valvular interstitial cell stress-strain state and concomitant phenotype. In the current study, a set of virtual biaxial stretch experiments were conducted on porcine pulmonary valve leaflet tissue photomicrographs via an image-based finite element approach. Stress distribution evolution during diastolic valve closure was predicted at both the tissue and cellular levels. Orthotropic material properties consistent with distinct stages of diastolic loading were applied. Virtual experiments predicted tissue- and cellular-level stress fields, providing insight into how matrix-to-cell stress transfer may be influenced by the inhomogeneous collagen fiber architecture, tissue anisotropic material properties, and the cellular distribution within the leaflet tissue. To the best of the authors' knowledge, this is the first study reporting on the evolution of stress fields at both the tissue and cellular levels in valvular tissue and thus contributes toward refining our collective understanding of valvular tissue micromechanics while providing a computational tool enabling the further study of valvular cell-matrix interactions.

A new species of the genus Sovia (Lepidoptera: Hesperiidae) from Qinling-Daba Mountains of China.

In this paper, a new species Sovia lii spec. nov. is described from Qinling-Daba Mountains in S. Gansu province and S. Shaanxi province, W. China. Variability of wing pattern, differences with its similar congeners and some biological information of this new taxon are introduced. External variability of Sovia lucasii, which is discovered from Shaanxi for the first time and is sympatric with the new species there, is illustrated and discussed. A brief analysis of the distributional pattern of the genus Sovia is provided. A key to the genus is given.

Review of the bicolora Fang and binghami Hampson species-groups of the genus Ovipennis Hampson with descriptions of five new species from Southwestern China and Indochina (Lepidoptera, Erebidae, Arctiinae, Lithosiini).

The Ovipennis bicolora Fang, 1986 and Ovipennis binghami Hampson, 1903 species-groups are reviewed. The identities of the records of O.binghami reported outside of its type locality are clarified. Ovipennis bicolora is rediscovered with the male and female genitalia illustrated for the first time. The male and female genitalia of O.thomasi ern, 2009 are illustrated for the first time and its specific status is confirmed. Five new species are described: O.hanae S.-Y. Huang, Volynkin & ern, sp. n. (Southwestern China), O.regina Volynkin, ern, S.-Y. Huang & Saldaitis, sp. n. (Northern Thailand and Southwestern China), O.takia Volynkin, S.-Y. Huang & ern, sp. n. (Western and Central Thailand), O.kitchingi Volynkin, S.-Y. Huang & ern, sp. n. (Northern Thailand), and O.sapa Volynkin, S.-Y. Huang, ern & Saldaitis, sp. n. (Northern Vietnam). Adults and genitalia of the new species are illustrated and compared with its congeners.

Notes on Aulocera pygmaea (Holik, 1949) and its related taxa (Lepidoptera, Nymphalidae, Satyrinae).

In this paper, Aulocera pygmaea (Holik, 1949) and its related taxa from W. China (S. Gansu, N. Sichuan, N.W. Yunnan, S.E. Tibet) and N. Myanmar (N. Kachin) are studied. The specific status of A. pygmaea (Holik) is confirmed based upon examining the syntype series. Aulocera atuntsensis (Gross, 1959), A. melanoleuca Sakai, Aoki & Yamaguchi, 2001 stat. nov., and A. auloceroides (H. Huang, 1999) are raised or restored to specific rank rather than treated as subspecies of A. pygmaea (Holik), as in Lang (2021). The lectotype for Satyrus sybillina pygmaea Holik, 1949 is designated. Other related taxa are also discussed.

A new species of the genus Eterusia Hope from western China (Lepidoptera, Zygaenidae, Chalcosiinae).

A new species Eterusia sinoraja Huang & Horie sp. n. is described from western Sichuan Province, western China. The comparison is made with the reminiscent E. raja Moore, 1859 from northeastern India. The adult and genitalia of both sexes of the aforementioned taxa are illustrated.

A review of the genus Agalope Walker (Lepidoptera, Zygaenidae, Chalcosiinae) with taxonomic notes and descriptions of three new genera and three new species.

A preliminary review of the genus Agalope Walker, 1854 is presented. Two new genera are established for four species-groups: Rotundagalope S.-Y. Huang & Horie, gen. n. (type species Agalope immaculata Leech, 1898, for the immaculata species-group), Paragalope S.-Y. Huang & Horie, gen. n. (type species Chelura pica Wileman, 1910, for the pica, glacialis and dejeani species-groups). An additional new genus, Agacysma S.-Y. Huang & Horie, gen. n., related to Agalope and Elcysma, is erected for the new species Agacysma sinica S.-Y. Huang & Horie sp. n. (mainland China: Chongqing, Hubei & Shaanxi). Two new species of the genus Agalope are described: A. geoffi S.-Y. Huang & Horie sp. n. (mainland China: SE. Xizang) and A. liuzihaoi S.-Y. Huang & Horie sp. n. (mainland China: SE. Xizang), forming a species-group of their own which is clearly different from congeners in their male genitalia. The taxonomic issues between Paragalope haoi (S.-Y. Huang, 2022) comb. n. and P. bieti (Oberthür, 1886) comb. n. are discussed. Moreover, following the erection of Paragalope, the homonymy of Agalope glacialis Butler, 1881 and A. glacialis (Moore, 1872) ends; hence the replacement name of the former, A. butleri Owada & Horie, 2000 syn. n., is unnecessary and hence synonymized. The following new combinations are given: Rotundagalope immaculata (Leech, 1898) comb. nov., Paragalope ardjuna (Roepke, 1936) comb. nov., P. aurelia (Oberthür, 1923) comb. nov., P. basiflava (Moore, 1879b) comb. nov., P. bieti (Oberthür, 1886) comb. nov., P. chayuensis (S.-Y. Huang & Pan, 2022) comb. nov., P. haoi (S.-Y. Huang, 2022) comb. nov., P. owadai (S.-Y. Huang, 2022) comb. nov., P. pica (Wileman, 1910) comb. nov., P. trimacula (Matsumura, 1927) comb. nov., P. wangi (Owada, 1992) comb. nov., P. dejeani (Oberthür, 1893) comb. nov., P. lucia (Oberthür, 1923) comb. nov., P. glacialis glacialis (Moore, 1872) comb. nov., P. glacialis parthenie (Jordan, 1907b) comb. nov., P. glacialis angustifasciata (Hering, 1922) comb. nov., P. glacialis postfasciata (Holloway, 2011) comb. nov. A checklist of the species and genera mentioned in the present study is given. Adults and genitalia of the newly described taxa and related ones are illustrated.

Taxonomic review of the genus Tarika Moore with descriptions of six new species from Nepal, China and Indochina (Lepidoptera: Erebidae: Arctiinae).

The Asiatic footman moth genus Tarika Moore, 1878, which used to be considered as monotypic is reviewed. Six new species are described: T. annapurna sp. n. (Сentral Nepal), T. erlanga sp. n. (China: Sichuan), T. reducta sp. n. (North Thailand), T. danieli sp. n. (China: Yunnan, Sichuan, Fujian, Shandong), T. kinha sp. n. (North Vietnam and China: Yunnan), and T. biserratula sp. n. (China: Hunan). Lectotypes are designated for Lithosia varana Moore, 1865 and Tarika nivea Moore, 1878. Adults, male and female genitalia are illustrated.

First record of the family Neopseustidae from Yunnan, China with description of a new species (Lepidoptera, Neopseustidae).

The family Neopseustidae is reported from Yunnan Province, Southwest China, for the first time, with a new species, N. gaoligongensis Huang & Chen, sp. n., described from Mt. Gaoligong, West Yunnan, based on molecular and morphological evidence. The new species was found to belong to the N. bicornuta species-group and is closely related to N. fanjingshana Yang, 1988, but can be distinguished from it by the differences in morphology and a 3.2% COI distance. Adults and genitalia of the new species and N. fanjingshana are illustrated, and the molecular phylogeny based on COI barcoding of the genus Neopseustis is also updated.

Taxonomic review of the Oriental genus Gandhara Moore with descriptions of four new species (Lepidoptera: Erebidae: Arctiinae: Lithosiini).

The genus Gandhara Moore, 1878 is reviewed. Four new species are described: Gandhara typica Volynkin & ern, sp. n. (Nepal, northeast India, northern Myanmar and northern Thailand), Gandhara clava Volynkin & ern, sp. n. (Laos and northern Thailand), Gandhara emgai Volynkin & ern, sp. n. (northern Vietnam), and Gandhara interrogativa Volynkin, ern, S.-Y. Huang & H.-L. Hu, sp. n. (northern Vietnam and southern China). Gandhara typica sp. n. is fixed as the type species of the genus Gandhara whereas Lithosia serva Walker, 1854 considered by authors as the type species of Gandhara by misidentification is transferred to the genus Collita Moore, 1878. Two new combinations are introduced: Gandhara conica (Fang, 2000), comb. n. and Collita serva (Walker, 1854), comb. n. A lectotype is designated for Lithosia serva Walker, 1854 in order to stabilise the nomenclature. Adults as well as male and female genitalia are illustrated.

Description of a new subspecies of Chonala laurae Bozano, 1999 from Southeastern China (Lepidoptera, Nymphalidae, Satyrinae).

The satyrid species Chonala laurae Bozano, 1999, formerly only known from southern Shaanxi and western Hubei Provinces in the central part of China, is recorded from Mt. Wuyi, Fujian Province in southeastern China for the first time, and the population is described as a new subspecies herein: C. laurae wuyishana Huang, Guo & Wang, ssp. n. The new subspecies can be distinguished from the nominate one by the pattern at the costa and in space 2 on the forewing upperside in males and the ground color in females, and from the closely related C. houae by the coloration of the pattern on the forewing upperside and in space 2 on the forewing underside as well as the male genital character. A brief discussion on the relationship among C. laurae laurae, C. laurae wuyishana ssp. n., and C. houae is also presented. In addition, an updated key to species and subspecies of Chonala is provided.

Taxonomic review of the Cyana adelina (Staudinger) species-group (Lepidoptera: Erebidae: Arctiinae) with descriptions of three new species and one new subspecies from Laos, Thailand and China.

The Cyana adelina (Staudinger, 1887) species-group is established and reviewed. Three new species and one new subspecies are described: Cyana yunnanensis regia ssp. n. (Northern Thailand and northern Laos), Cyana dubernardi sp. n. (China: Yunnan), Cyana khami sp. n. (central Laos), and Cyana karsticola sp. n. (northern Laos). Two new synonyms are established: Cyana yunnanensis yunnanensis (Hampson, 1903) (Chionaema) = Chionaema hoenei Daniel, 1952, syn. n., and Cyana griseilinea de Joannis, 1930 = Cyana succincta ern, 2016, syn. n. Lectotypes are designated for Bizone adelina Staudinger, 1887 and Bizone pratti Elwes, 1890. Adults, male and female genitalia are illustrated.

Contribution to the knowledge of the genus Nephelomilta Hampson, 1900(Lepidoptera, Erebidae, Arctiinae) from China with descriptions of two new species.

New information on the genus Nephelomilta Hampson, 1900 from China is reported. Two new species are described from southwestern China: N. medogensis Huang, Volynkin & Saldaitis, sp. n. from Motuo County, Xizang Autonomous Region and N. nu Huang, Volynkin & Saldaitis, sp. n. from Nujiang Valley, Yunnan Province. The female of N. yasunorikishidai Huang & Wang, 2019 is discovered and illustrated for the first time, and the species is erected into a separate species-group. Adults and genitalia of the aforementioned taxa and related ones as well are illustrated.

Letrasilta, a new genus for the Striatella cernyi Volynkin species-group with description of a new species from Xizang, China, and a replacement name for the genus group name Striatella Volynkin & S.-Y. Huang, 2019 (Lepidoptera: Erebidae: Arctiinae: Lithosiini).

The name Striatochrista nom. n. is introduced as replacement for Striatella Volynkin & S.-Y. Huang, 2019. A new genus, Letrasilta S.-Y. Huang & Volynkin gen. n. is erected to include the Striatella cernyi species-group with the new species, L. ratnasambhava S.-Y. Huang, Volynkin & Yin sp. n. from Xizang, southwestern China designated as the type species. Based on the molecular phylogenetic analysis, the new genus is found to be sister to the clade (Aberrasine + ((Indiania + Idopterum) + Striatochrista nom. n.)) but is distinguished from all the relevant genera by the unique genitalia features. Letrasilta cernyi (Volynkin, 2018) comb. n. is also reported from India for the first time. Adults and genitalia of the aforementioned taxa are illustrated. A checklist of the genus Striatochrista is also provided.