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IntroductionPine wilt disease (Bursaphelenchus xylophilus) was recently detected in Liaoning Province, which was previously considered an unfavourable area for B. xylophilus due to its low temperatures. This study aims to compare the reproductivity and genetic variations of B. xylophilus isolates from Liaoning Province and other parts of China to explore their phenotypic and genomic differences.MethodsThe samples from Liaoning, Anhui, Hubei, Henan, Zhejiang and Jiangsu were isolated and purified to obtain the strains. The reproductivity of the strains was determined at 15 °C. The genetic structure was analyzed by using SNP molecular markers, and the whole genome association analysis was carried out by integrating SNP information and feculence traits.ResultsA reproductivity experiment showed that Liaoning isolates have higher reproductive ability at 15 °C. Subsequent SNP profiling and population differentiation analysis revealed obvious genetic differentiation of Liaoning isolates from other isolates. A genome-wide association study showed that SNPs closely related to low-temperature tolerance were mainly located in GPCR, Acyl-CoA, and Cpn10, which are responsible for adaptation to environmental factors, such as temperature change.DiscussionPine wood nematodes likely adapted to the climate in Liaoning and maintained a certain reproductive capacity at low temperature via variants of adaptation-related genes. This study provides a theoretical basis for elucidating the prevalence and diffusion status of B. xylophilus in China.

The remarkable efficacy of COVID-19 vaccines has established mRNA as a highly promising biomedical technology. However, the adequate application of mRNA therapeutics necessitates additional measures to mitigate the inherent immunogenicity, which is predominantly caused by dsRNA. As a byproduct of the in vitro transcription of mRNA, dsRNA was reported to be originated through several distinct mechanisms, including the extension of 3′ loop-back hairpins, the extension of hybridized abortive transcripts, and promoter-independent transcription. The intricate mechanisms involved pose a dilemma as the reduction in dsRNA results in a concomitant decrease in other critical quality attributes of mRNA. Here, we demonstrate that the promoter binding motifs of T7 RNA polymerase directly impact the production of promoter-independent transcription-based dsRNA. Specifically, the G753A mutation significantly reduces the formation of dsRNA byproducts, which can further combine with modified nucleotides to enhance the effectiveness of dsRNA mitigation and with previously reported high-integrity mutation K389A to minimize side effects. Accordingly, the present study reports a cost-effective approach to synthesize high-purity, less immunostimulatory mRNA by using an engineered T7 RNA polymerase mutant. [ABSTRACT FROM AUTHOR]

Simvastatin is a widely used statin medication that is commonly prescribed to lower cholesterol levels and reduce the risk of cardiovascular events. It is marketed under the brand name Zocor and is known for its effectiveness in treating high cholesterol and managing cardiovascular disease. Monacolin J is an important precursor used to synthesize simvastatin and is mainly produced by chemical methods in industry. Here, monacolin J was synthesized through an enzymatic method under optimized reaction conditions. One recombinant Escherichia coli BL21 (DE3) strain containing lovastatin hydrolase (encoded by CDV55_102090) from Aspergillus turcosus was constructed, which effectively transformed 100 g/L of lovastatin to monacolin J within 3.5 h at pH 8.0 and 30 °C, with a conversion rate of >99.8%. Furthermore, the T5010, the temperature at which the residual activity was half of the initial enzymatic activity after 10 min of heat treatment, was >50 °C, indicating the tremendous potential of this bioprocess for synthesizing monacolin J at an industrial scale. [ABSTRACT FROM AUTHOR]

Pine wilt disease (PWD) is a severe threat to pine forests in East Asia. Screening and breeding of resistant varieties is a very effective way to prevent and control PWD; however, no reliable somatic embryogenesis system has yet been developed for the elite nematode-resistant Pinus thunbergii Parl. line. In this study, we studied the plant regeneration via somatic embryogenesis of nematode-resistant P. thunbergii. Initiation of embryogenic tissue was significantly affected by seed family (p = 0.017), immature zygotic embryo stage (p = 0.032), and initiation medium (p = 0.004). Seed family 37 was the most favorable female parent for initiation ofP. thunbergii. Furthermore, the initiation rate increased from the pre-embryonic stage to the cleavage polyembryonic stage. The optimal medium was I2, containing 2,4-dichlorophenoxyacetic acid (9 [micro]mol x [L.sup.-1]) and 6-benzyladenine (4.4 [micro]mol x [L.sup.-1]). A statistically significant interaction between cell line and subculture time (24 months) was observed in the influence on proliferation rate, somatic embryo production, and percentage germination (p < 0.001). In this study, the highest somatic embryo production was achieved using cell line 37-1 (1983 somatic embryos per gram fresh mass), with approximately 83.5% of somatic embryos germinating after transferring to germination medium, of which 77.6% converted into plantlets. Key words: somatic embryogenesis, regeneration, pine wilt disease, Pinus thunbergii. La fletrissure du pin constitue une menace serieuse dans les forets de pin de l'est de l'Asie. La selection et le developpement de varietes resistantes sont des facons tres efficaces de prevenir et de maitriser la fletrissure du pin; cependant, aucun systeme fiable d'embryogenese somatique n'a encore ete developpe pour la lignee elite de Pinus thunbergii Parl. resistante au nematode responsable de la maladie. Dans cette etude nous avons examine la regeneration de plants de P. thunbergii resistants au nematode par embryogenese somatique. L'initiation du tissu embryogene etait significativement influence par la famille de graines (p = 0,017), le stade de l'embryon zygotique immature (p = 0,032) et le milieu utilise pour l'initiation (p = 0,004). La famille de graines 37 etait le parent femelle le plus favorable pour l'initiation de P. thunbergii. De plus, le taux d'initiation augmentait du stade preembryonnaire au stade de clivage polyembryonnaire. Le milieu optimal etait I2, contenant l'acide 2,4-dichlorophenoxyacetique (9 [micro]mol x [L.sup.-1]) et la 6-benzyladenine (4,4 [micro]mol x [L.sup.-1]). Une interaction statistiquement significative entre la ligne de cellules et le temps passe en sous-culture (24 mois) a ete observee dans le cas de l'influence sur le taux de propagation, de la production d'embryons somatiques et du pourcentage de germination (p < 0,001). Dans cette etude, la plus forte production d'embryons somatiques a ete obtenue avec la lignee de cellules 37-1 (1983 embryons somatiques par gramme de masse frais), avec approximativement 83,5 % des embryons somatiques qui germaient apres avoir ete transferes sur le milieu de germination et dont 77,6 % se transformaient en plantules. [Traduit par la Redaction] Mots-cles: embryogenese somatique, regeneration, fletrissure du pin, Pinus thunbergii., 1. Introduction Japanese black pine (Pinus thunbergii Parl.), which is native to southern coastal regions of Japan and South Korea, has been widely cultivated in China (Taki et al. 2014). [...]

Introduction: Pine wilt disease (Bursaphelenchus xylophilus) was recently detected in Liaoning Province, which was previously considered an unfavourable area for B. xylophilus due to its lowtemperatures. This studyaims tocomparethe reproductivity and genetic variations of B. xylophilus isolates from Liaoning Province and other parts of China to explore their phenotypic and genomic differences. Methods: The samples from Liaoning, Anhui, Hubei, Henan, Zhejiang and Jiangsu were isolated and purified to obtain the strains. The reproductivity of the strains was determined at 15 °C. The genetic structure was analyzed by using SNP molecular markers, and the whole genome association analysis was carried out by integrating SNP information and feculence traits. Results: A reproductivity experiment showed that Liaoning isolates have higher reproductive ability at 15 °C. Subsequent SNP profiling and population differentiation analysis revealed obvious genetic differentiation of Liaoning isolates from other isolates. A genome-wide association study showed that SNPs closely related to low-temperature tolerance were mainly located in GPCR, Acyl-CoA, and Cpn10, which are responsible for adaptation to environmental factors, such as temperature change. Discussion: Pine wood nematodes likely adapted to the climate in Liaoning and maintained a certain reproductive capacity at low temperature via variants of adaptation-related genes. This study provides a theoretical basis for elucidating the prevalence and diffusion status of B. xylophilus in China. [ABSTRACT FROM AUTHOR]

In previous research, the pine wood nematode Bxadh2 gene significantly increased its expression in pine seedlings inoculated with endophytic Bacillus cereus GD2 and pine wood nematode. To explore pine wood nematode Bxadh2 gene function, we cloned and analyzed its biological information, and we preliminarily studied its physiological function through RNA interference. We found that the Bxadh2 gene's full CDS length is 1269 bp, which encodes 422 amino acids, and presents a relatively stable hydrophobic protein. The protein encoded by the Bxadh2 gene has no signal peptide or transmembrane structure, and it is an intracellular protein that does not participate in transmembrane movement. The RNAi interference results showed that when the pine wood nematode's Bxadh2 gene was suppressed, its survival rate and fecundity significantly decreased, indicating that the expression of the Bxadh2 gene was related to the growth and development of pine wood nematodes. [ABSTRACT FROM AUTHOR]