Sheng wu gong cheng xue bao = Chinese journal of biotechnology最新文献

To clarify the genetic diversity and structure of the nucleus population of F1-generation Litopenaeus vannamei, this study utilized 15 pairs of highly polymorphic microsatellite primers to analyze the simple sequence repeat (SSR) markers and genetic diversity in 15 full-sib families of L. vannamei. A total of 112 alleles (N_a) and 60.453 effective alleles (N_e) were identified among the selected 15 SSR loci, with the average polymorphic information content (PIC) of 0.648. The average N_e, observed heterozygosity (H_o), and expected heterozygosity (H_e) in the 15 F1 families varied from 1.925 to 2.626, 0.425 to 0.783, and 0.403 to 0.572, respectively. The 15 full-sib families were primarily clustered into three categories in the phylogenetic analysis, with the genetic distance between families ranging from 0.252 to 0.574. Additionally, the genetic differentiation coefficient (F_st) among the families varied from 0.112 to 0.278, indicating substantial genetic differentiation. Overall, this study suggested that the genetic diversity of the 15 full-sib families was moderate, providing valuable genetic insights for the subsequent breeding initiatives aimed at enhancing the tolerance of L. vannamei to high levels of soybean meal.

The aim of this study was to compare the immune responses of C57BL/6 mice immunized with two pathogens, foot-and-mouth disease virus (FMDV) and Senecavirus A (SVA), and to provide clues for revealing the regulatory mechanisms of acquired immunity. Inactivated and purified FMDV and SVA antigens were used to immunize C57BL/6 mice respectively, and the mice immunized with PBS were taken as the control. The percentages of Th1 and Th2 cells in the spleen lymphocytes of mice in each group were analyzed by flow cytometry at 14 and 28 days after immunization. RNA-Seq was performed for the spleen. Mouse macrophages were stimulated with the antigens in vitro to examine the expression of the differentially expressed genes (DEGs) screened out. The results showed that 14 days after immunization, there was no significant difference in the magnitude of the Th1/Th2 immune response elicited by the FMDV and SVA antigens. After 28 days, the magnitudes of the Th1 and Th2 immune responses elicited by the SVA antigen were higher than those elicited by the FMDV antigen. RNA-Seq revealed two common DEGs, Rsad2 and Tspan8, between the two immunization groups, which indicated that the two genes may be involved in the activation of the Th1/Th2 immune responses by FMDV and SVA antigens. FMDV and SVA antigens stimulated macrophages to secrete interleukin (IL)-12 and IL-33 in vitro, and the expression of Tspan8 and Rsad2 was consistent with the RNA-Seq results. The expression of Rsad2 was regulated by type I interferons (IFNα, IFNβ). In this study, we obtained the DEGs involved in the immune responses to the two antigens in mouse spleen, which provides a molecular basis for investigating the immune response mechanisms induced by FMDV and SVA.

Retinoic acid signaling pathway plays a role in regulating vertebrate development, cell differentiation, and homeostasis. As a key enzyme that catalyzes the oxidation of retinal to retinoic acid, aldehyde dehydrogenase 1 family member A2 (Aldh1a2) is involved in cardiac development, while whether it functions in heart diseases remains to be studied. In this study, we infected primary cardiomyocytes with adenovirus overexpressing Aldh1a2 (Ad-Aldh1a2) to explore the effects of Aldh1a2 overexpression on the biological function of cardiomyocytes. The results showed that the infection with Ad-Aldh1a2 realized the overexpression of Aldh1a2 in cardiomyocytes. Compared with the control group infected with Ad-GFP, the cardiomyocytes infected with Ad-Aldh1a2 showcased significantly increased size and up-regulated expression levels of the atrial natriuretic factor gene (ANF), brain natriuretic peptide gene (BNP), and β-myosin heavy chain (β-MHC). In addition, 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay demonstrated that Aldh1a2 overexpression increased the proportion of cardiomyocytes with positive EdU signals and upregulated the expression levels of proliferation-related genes cyclin D2 (Ccnd2) and budding uninhibited by benzimidazole 1 (Bub1). The above data indicated that overexpression of Aldh1a2 induced hypertrophic growth and proliferation of cardiomyocytes. This study provides a basis for further understanding the function of Aldh1a2 in heart diseases and developing therapies for heart diseases.

Ten-eleven translocation 1 (TET1) protein is an alpha-ketoglutaric acid (α-KG) and Fe²⁺-dependent dioxygenase. It plays a role in the active demethylation of DNA by hydroxylation of 5-methyl-cytosine (5-mC) to 5-hydroxymethyl-cytosine (5-hmC). Ten-eleven translocation 1 (TET1) protein is involved in maintaining genome methylation homeostasis and epigenetic regulation. Abnormally expressed TET1 and 5-mC oxidative derivatives have become potential markers in various biological and pathological processes and a research focus in the fields of embryonic development and malignant tumors. This paper introduces the structure and demethylation mechanism of TET1, reviews the research status of epigenetic regulation by TET1 in embryonic development, immune responses, stem cell regulation, cancer progression, and nervous system development, and briefs the upstream regulatory mechanism of TET1, hoping to provide new inspirations for further research in related fields.

Nanobodies (Nbs), the unique single-domain antibodies discovered in the species of Camelidae and sharks, are also known as the variable domain of the heavy chain of heavy-chain antibody (VHH). They offer strong antigen targeting and binding capabilities and overcome the drawbacks such as large size, low stability, high immunogenicity, and slow clearance of conventional antibodies. Nbs can be boosted by bioconjugation with toxins, enzymes, radioactive nucleotides, fluorophores, and other functional groups, demonstrating potential applications in the diagnosis and treatment of human and animal diseases. This article introduces the structures and characteristics of Nbs, the construction and screening of Nb libraries, and the strategies for affinity maturation and then reviews the current applications of Nbs in diagnosis and treatment, providing a reference for the development of diagnostic reagents and clinical therapies for infectious diseases.

Dengue fever is a mosquito-borne disease prevalent in tropical and subtropical regions, with its prevalence expanding due to increased global travel. The dengue virus, the causative agent of dengue fever, often co-circulates in the form of four distinct serotypes. Cross-reactive antibodies generated during a primary infection pose a significant risk during secondary infections with different serotypes, and fully protective vaccines and antiviral drugs are yet to be developed. Over the past decade, advances in antibody technology have led to the isolation of numerous monoclonal antibodies against dengue virus, with their neutralizing epitopes elucidated through structure-based analyses. This review highlights the key epitopes associated with neutralizing antibodies against dengue virus and discusses their potential applications in vaccine design and therapeutic antibody development. This review helps systematically summarize the progress in dengue virus neutralizing antibody research, providing a theoretical foundation and technical guidance for the development of novel vaccines and antibody therapeutics.

In order to establish a stable in vitro culture platform for chicken small intestine three-dimensional (3D) organoids, in this study, crypt cells were collected from the small intestine of 18-day-old embryos of AA broilers. On the basis of the L-WRN conditioned medium, we optimized the culture conditions of chicken small intestinal organoids by adjusting the proportions of nicotinamide, N-acetylcysteine, LY2157299, CHIR99021, Jagged-1, FGF, and other cytokines to select the medium suitable for the long-term stable growth of the organoids. The optimization results showed that the addition of 1.5 µmol/L CHIR99021 significantly improved the organoid formation efficiency and organoid diameter. When 0.5 µmol/L Jagged-1 was added, a small amount of bud-like tissue appeared in organoids. After the addition of 50 ng/mL FGF-2, the rate of organoid germination was significantly increased. The 1.5 µmol/L CHIR99021, 0.5 µmol/L Jagged-1, and 50 ng/mL FGF-2 added in the medium can cooperate with each other to improve the formation and speed up the proliferation and differentiation of organoids, while improving the stemness maintenance of cells. The morphology, cell types, and culture characteristics of chicken small intestinal organoids were studied by HE staining, transmission electron microscopy, reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), indirect immunofluorescence, and immunohistochemistry. The results showed that the 3D organoids of the chicken small intestine cultured in vitro were morphologically consistent with the chicken intestinal tissue and contained differentiated epithelial cells. In summary, we successfully established an in vitro culture system for chicken small intestinal organoids, providing a new method for the subsequent research on chicken intestinal physiology, pathology, and host-pathogen interaction mechanism and the development of relevant drugs.

This study developed ferritin-based nanoparticles carrying the African swine fever virus (ASFV) p30 protein and evaluated their immunogenicity, aiming to provide an experimental basis for the research on nanoparticle vaccines against ASFV. Initially, the gene sequences encoding the p30 protein and SpyTag were fused and inserted into the pCold-I vector to create the pCold-p30 plasmid. The gene sequences encoding SpyCatcher and ferritin were fused and then inserted into the pET-28a(+) vector to produce the pET-F-np plasmid. Both plasmids were expressed in Escherichia coli upon induction. Subsequently, the affinity chromatography-purified p30 protein was conjugated with ferritin in vitro, and the p30-ferritin (F-p30) nanoparticles were purified by size-exclusion chromatography. The morphology and structural integrity of F-p30 nanoparticles were examined by a particle size analyzer and transmission electron microscopy. Mice were immunized with F-p30 nanoparticles, and the humoral and cellular immune responses were assessed. The results showed that F-p30 nanoparticles were successfully prepared, with the particle size of approximately 20 nm. F-p30 nanoparticles were efficiently internalized by bone marrow-derived dendritic cells (BMDCs) cells in vitro. Compared with the p30 protein alone, F-p30 nanoparticles induced elevated levels of specific antibodies and cytokines in mice and stimulated the proliferation of follicular helper T cell (T_FH) and germinal center B cell (GCB) in lymph nodes as well as CD4⁺ and CD8⁺ T cells in the spleen. In conclusion, we successfully prepared F-p30 nanoparticles which significantly enhanced the immunogenicity of p30 protein, giving insights into the development of vaccines against ASFV.

Metallothionein (MT) plays a significant role in heavy metal removal, antioxidant defense, and immune regulation. The current predominant approach for obtaining natural MT is extraction from tissue, which often entails complex procedures resulting in limited yields. In recent years, researchers have adopted the strategy of fusing labels such as GST or His for the heterologous expression of MT. However, a challenge in industrial production arises from the subsequent removal of these labels, which often leads to a significant reduction in the yield. The fusion with elastin-like polypeptides (ELPs) offers a promising solution for achieving soluble expression of the target protein, while providing a simple and fast purification process. In this study, ELP was fused with MT, which significantly up-regulated the soluble expression of MT. The fusion protein ELP-MT with the purity above 97% was obtained efficiently and simply by inverse transition cycling (ITC). ELP-MT exhibited a remarkable 2,2'-azinobis(3-ethylbenzothiazoline-6- sulfonic acid) ammonium salt (ABTS) scavenging activity, with the half maximal inhibitory concentration (IC₅₀) of 0.77 μmol/L, which was 53.7 times that of the vitamin E derivative Trolox. In addition, the fusion protein demonstrated strong 1,1-diphenyl-2-trinitrohydrazine (DPPH) scavenging ability. Furthermore, ELP-MT had no toxicity to the proliferation and promoted the adhesion and migration of NIH/3T3 cells. All these results indicated that ELP-MT had good biocompatibility. We constructed the fusion protein ELP-MT combining the unique properties of MT and elastin, laying a technical foundation for the large-scale production of recombinant MT and facilitating the applications in food, health supplement, and cosmetic industries.

Protein phosphorylation plays a key role in Mycobacterium tuberculosis, the pathogen of tuberculosis, holding promise as a new target of anti-tuberculosis drugs. We used M. smegmatis, a close relative of M. tuberculosis, as a model organism to study the protein phosphorylation at different growth phases. We identified 573 phosphorylated peptides and 816 phosphorylated sites of 385 proteins in the M. smegmatis samples at both logarithmic and stationary phases, and then established a comprehensive dataset of phosphorylated proteins in M. smegmatis. By comparing the expression levels of phosphorylated proteins between the logarithmic and the stationary phase with the selected ion monitoring (SIM) strategy, we verified 68 upregulated proteins involved in cell division and protein translation, and 69 downregulated proteins mainly involved in the tricarboxylic acid cycle pathway. The differentially expressed phosphorylated proteins were significantly enriched in important cellular cycle events such as cell elongation and division. The findings of this study provide proteome evidence for elucidating the phosphorylation in both M. smegmatis and M. tuberculosis.