Phosphoribulokinase (PRK) is a key enzyme in Calvin-Benson cycle which influences on plant growth and development. Nuclear-encoded plastid-localized PRK, coupling with other regulatory enzyme,involved in carbon assimilation in functional leaves. However, the research on RPK functions in stress response was still limited, especially in rice (Oryza sativa). In this study, target protein subcellular localization, expression characteristics analyses of rice phosphoribulokinase (OsPRK, GenBank No. LOC4330413) under abiotic stresses (drought, high salt and high temperature) and exogenous hormone treatments (abscisic acid (ABA), jasmonic acid (JA) and salicylic acid (SA)), as well as MBP pull-down protein interaction screening were conducted to investigate the function of OsPRK involving in stress responses. By detecting the GFP report using laser confocal microscopy, the transient expression analysis demonstrated that OsPRK was strictly localized in chloroplast stroma of transformed rice protoplasts after 16 h protoplast culture, contrasting to control native GFP only found around the cytoplasm of protoplast. To characterize the change of the transcript abundance of OsPRK, quantitative realtime PCR (qPCR) was performed and found that the transcriptional expression of OsPRK was significantly inhibited at 0.5 and 3 h drought treatments, 1 and 6 h high salt or high temperature treatments, which implicated that OsPRK inclined to reduce transcriptional expression in drought, high salt and high temperature conditions. Beyond that, qPCR results also showed that the OsPRK transcription levels of seedlings under ABA and JA treatments were not significantly changed within 1 h, while continuously decreased when treated more than 4 h. Unlike ABA and JA treatment, the transcription level of OsPRK of SA treatment had a dramatical reduction from 0 to 8 h, and then gradually declined until 24 h. To investigate the potential OsPRK interacting proteins, OsPRK was expressed with MBP-Tag using recombinant plasmid pMAL-c5x and purified from BL21(DE3)plys prokaryotic expression system for pull-down protein interaction screening. The protein interaction experiment totally obtained 82 candidate proteins that might interact with OsPRK using MBP pull-down method. Of these, the functions of 67 candidate proteins were unknown while 15 candidate proteins were with known functions, including GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and WRKY transcription factor. This study found that OsPRK should be involved in abiotic stress and hormone response of rice seedlings. In addition, the study identified numbers of potential OsPRK interacting proteins, which can be used for further biological functions of OsPRK in stress avoidance and tolerance. All these findings accelerated the understanding of OsPRK roles in response to developmental requirements and environmental constraints.

Plant height and tiller number are important agronomic traits affecting rice (Oryza sativa) yield. Appropriate plant height and tiller number are beneficial to increase rice yield. In this study, a semi-dwarf mutant with multi-tiller, sd-fh7185 (semi-dwarf from Fuhui 7185), was screened from the mutant library of indica restorer line 'Fuhui 7185' (FH7185) with chemical mutating of 0.1% ethylmethylsulfone (EMS). The investigated and analyzed results showed that the plant height of sd-fh7185 decreased significantly at seedling stage, tillering stage and maturity stage compared with wild type FH7185 (P<0.01), the decrease of plant height was mainly caused by the shortening of panicle and the first internode, and sd-fh7185 was controlled by a single recessive nuclear gene located on chromosome 3 (Chr. 3) in rice. Map-based cloning results indicated that the target gene, sd-fh7185, was finally fine-mapped within a physical interval of about 120 kb between InDel markers ID73 and GH25 on Chr. 3. The target region contained 14 predicted functional genes, one of which was a documented dwarf multi-tiller gene tensinte branched 1 (OsTB1)/fine cuml 1 (FC1) (MSU-RGAP locus LOC_Os03g49880) in rice. The sequencing results revealed a single base substitution from C (FH7185, wild type, WT) to T (sd-fh7185) occurred at position 439 bp of the exon of LOC_Os03g49880 in sd-fh7185, which resulted in a premature termination, and the length of encoded product was shortened from 388 amino acids (WT) to 146 amino acids (sd-fh7185) with changed function. Summarily, sd-fh7185 was a newly identified allele of OsTB1/FC1 differed from previously reported fc1-1 and fc1-2, which enriched the semi-dwarf and multi-tillering gene resources in rice, and the results provide informative references for both the dissection of molecular mechanism and rice morphology breeding in rice.

Fruit ripening is regulated by a variety of plant hormones, such as ethylene, abscisic acid (ABA) and gibberellin (GA), and ripening-related genes. SlGA2ox (SlGA2-oxidase) family are key genes for regulating GA metabolism and play significant role in regulating tomato (Solanum lycopersicum) fruit ripening. Nevertheless, the specific role of SlGA2ox in maturation-related GA metabolism and its interaction with ethylene and ABA remain unclear. In this study, 15 SlGA2ox genes were screened based on the tomato genome database, and the role of SlGA2ox during maturation process was explored through promoter element prediction, gene expression analysis, and the response analysis to GA, ethylene and ABA. The results showed that 12 SlGA2ox genes were closely related to tomato fruit ripening. Among them, SlGA2ox2, SlGA2ox5, SlGA2ox6 and SlGA2ox8 might be regulated by ethylene in the process of mediating GA metabolism, while SlGA2ox4 and SlGA2ox5 might be regulated by ABA at the same time. In addition, SlGA2ox5 was regulated by both ABA and ethylene signals, so it might be a key gene in the fruit ripening which was regulated jointly by the 3 hormones. The present study provides basic material for in-depth exploration of the genes related to tomato fruit ripening regulation, and provides important clues for exploring the molecular mechanism of tomato fruit ripening regulation.

Dirigent genes (DIRs) are important regulator in the biosynthesis of plant lignin and lignans, and play pivotal roles in plant growth and development, and stress response. In order to explore the function of SlDIR family genes in tomato (Solanum lycopersicum), bioinformatics analysis of SlDIR members were carried out and expression characteristics of them in different organs, various stresses and abscisic acid (ABA) treatments were detected by released RNA-seq in TFGD website and qPCR. The results showed that 31 SlDIR genes were identified in tomato, which were unevenly distributed on 11 chromosomes (except Chr03) with 3 tandem duplication clusters. Most of SlDIR genes had no intron. The phylogenetic analysis displayed that the SlDIR family mumbers were classified into 3 subfamilies, the member numbers of which were various. All of SlDIR proteins had dirigent domain, and most of them also contained signal peptide. The distribution and arrangement of the motifs in SlDIRs from the same subfamily were similar. In addition, plant hormone and stress response elements were widely distributed in the promoter regions of SlDIRs. The expression characteristics of SlDIRs in different organs and different resistant materials under Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) treatment were further analyzed. It was found that most SlDIRs were predominance expressed in roots, and the expressions of SlDIR5, SlDIR9, SlDIR13, SlDIR15 and SlDIR27 were significantly higher in the early stages than that in the later stages of tomato fruit development. The significantly different expressions of 11 SlDIRs were displayed between resistant and sensitive tomato varieties under Pst DC3000 treatment. Under ABA treatment for 12 h, the expressions of 7 SlDIRs were significantly up-regulated. Salt stress significantly induced the expression of SlDIR27. Meanwhile, SlDIR13 and SlDIR27 showed up-regulated expressions significantly under drought treatment. The results of this study provide a reference for further study on the biological functions of SlDIR family genes.

Leaf number is one of the important factors affecting the yield of flue-cured tobacco (Nicotiana tabacum). To improve the efficiency of leaf number genetic improvement, this studying took the flue-cured tobacco variety 'NC82' with few leaves and the flue-cured tobacco variety 'Jiucaiping 2' with many leaves as the parents, constructed F₁ and F₂ genetic populations, and conducted genetic analysis on the leaf number of 'Jiucaiping 2'. Bulked segregant analysis coupled with whole-genome sequencing (BSA-seq) and kompetitive allele-specific PCR (KASP) were used to map the leaf numbers of 'Jiucaiping 2'. The results showed that the number of leaves of the flue-cured tobacco variety 'Jiucaiping 2' was a quantitative trait mainly controlled by additive effect genes. At the same time, it was regulated by genes with partial recessive relationships, and the number of leaves was partially dominant. BSA-seq technology was used for initial mapping, combined with the Δ(SNP-index) locus and euclidean distance (ED) locus association analysis obtained by sequencing, the candidate range of leaf number was located in the 6.96 Mb range of chromosome 9. According to the SNP genotypes obtained by resequencing, KASP markers were developed in the candidate region to detect F₂ individual genotypes, and the candidate gene of leaf number was further reduced to the 1.92 Mb region, which contained 37 genes. Sequence analysis and functional prediction of genes within this region indicated 8 key genes controlling leaf number traits of 'Jiucaiping 2'. This study provides basic data for further clarifying key genes regulating leaf number of flue-cured tobacco in 'Jiucaiping 2', improving yield breeding efficiency of flue-cured tobacco, and revealing the molecular mechanism of leaf number formation of flue-cured tobacco.

Zinnia elegans is widely used in garden, flower border and other landscape greening, anthocyanin is one of the important pigments affecting flower coloration. basic helix-loop-helix (bHLH) transcription factors are the second largest family of transcription factors regulating anthocyanin synthesis. Among them, bHLH proteins related to flower color mainly belong to IIIf subgroup. At present, the regulation of anthocyanin synthesis by bHLH transcription factors in Z. elegans is unclear. In this study, the content of anthocyanins in the petals of 6 cultivars with different petal colors at different developmental stages of Z. elegans 'Dreamland' series was determined. Results showed that the content of anthocyanin in the petals of pink, rose, orange and red colors was the lowest at bud stage and the highest at half opening stage. The content of anthocyanins in the petals of red cultivar was the highest, followed by rose cultivar, while there was no anthocyanin in the petals of white and yellow cultivars. Based on the transcriptome data, 67 bHLH transcription factors were screened. Among them, ZeGL3 (Z. elegans glabra 3)(GenBank No. UXP87119.1) and ZeTT8 (Z. elegans transparent testa 8)(GenBank No. OP747298) belonged to the IIIf subgroup of bHLH family. Both ZeGL3 and ZeTT8 amino acid sequences contained conserved domains of MYB interaction region, bHLH and ACT. The expression level of ZeGL3 gene was the highest in petals, while the expression level of ZeTT8 gene was significantly higher in both petals and phyllaries. The expression of ZeGL3 gene in rose and red cultivar was generally higher than that in pink and coral cultivars (P<0.05). Through comprehensive analysis, it was considered that ZeGL3 gene was probably involved in the regulation of anthocyanin metabolism of Z. elegans. This study provides a theoretical basis for further revealing the molecular mechanism of IIIf subgroup gene of bHLH family regulating anthocyanin metabolism in Z. elegans.

Moso bamboo (Phyllostachys edulis) is an important economic bamboo species in China. The normal development of bamboo bud/shoot determines its yield. The MONOCULM1 (MOC1) gene plays an important role in the formation and development of axillary meristems and axillary buds. In this study, 2 MOC1 homologous genes, PheMOC1a (GenBank No. ON804247) and PheMOC1b (GenBank No. ON804248), were obtained from moso bamboo by RT-PCR. The sequence analysis showed that the ORFs of PheMOC1a and PheMOC1b were 1 530 and 1 293 bp, encoding 509 and 430 amino acid, respectively. Both polypeptide chains contain GRAS-superfamily conserved domains and belong to the GIBBERELLIN ACID INSENSITIVE (GAI), REPRESSOR of GA1 (RGA) and SCARECROW (SCR) (GRAS) gene family. Phylogenetic tree showed that PheMOC1a/b was closely related to MOC1 in rice (Oryza sativa). qRT-PCR results showed that the PheMOC1a and PheMOC1b showed obvious tissue-specific expression. PheMOC1a and PheMOC1b showed opposite expression characteristics in the bamboo bud/shoot at different developmental stages. With the development of bamboo bud/shoot, the expression of PheMOC1a decreased, while the expression of PheMOC1b increased. The trend of PheMOC1a and PheMOC1b expression was opposite in the branches at different developmental stages. The results of yeast two-hybrid and bimolecular fluorescence complementation showed that PheMOC1a and PheMOC1b not only interacted with themselves, but also interacted with each other, and interacted with 2 members of the indeterminate domain (IDD) family. These interacting proteins played biological roles in the nucleus. This study provides a reference for further analysis of the biological functions of PheMOC1a/b, and basic information for the molecular mechanism of bamboo bud/shoot development in moso bamboo.

Myostatin (MSTN) negatively regulates skeletal muscle growth, and the animals carrying the mutated gene all show better growth performance and meat production performance than the normal animals. Whether the significantly increased meat yield will affect the quality of meat is a general concern of consumers. In this study, the MSTN gene-edited cattle (Bos taurus) were used to examine the slaughter traits and meat quality indexes. The results showed that the slaughter rates of MSTN edited cattle and control cattle were (60.83±4.68)% and (55.71±0.53)%, and the net meat rates were (40.63±2.00)% and (37.62±0.79)%, respectively, with significant differences (P<0.05). The meat quality indexes such as pH value, tenderness, water power and nutrition of MSTN-edited cattle were all with no significant differences compared with the control cattle. Gene expressions of longissimus dorsi muscle detected by RNA-Seq and qPCR showed that MSTN mutation resulted in down-regulation of the genes associated with fat synthesis such as Adiponectin, C1Q and collagen domain containing (ADIPOQ), fatty acid binding protein 4 (FABP4), fatty acid synthase (FASN), lipoprotein lipase (LPL), peroxisome proliferator-activated receptor γ (PPARγ), and stearoyl-CoA desaturase (SCD), decreased the intermuscular fat, and increased the lean meat production. In conclusion, the artificial mutation of MSTN gene can significantly improve the meat production performance of Luxi cattle, not change the meat quality, reduce intramuscular fat deposition, and improve the lean meat production.

miR-206 is one of the miRNAs previously screened by our group by whole-transcriptome sequencing which showed significant differences in high and low residual feed intake in beef cattle (Bos taurus). Cattle miR-206 was used as a study target to analyze the affinity of miR-206 among species, and the potential target genes of bovine miR-206 were predicted by online software such as TargetScan and miRWalk. GO and KEGG enrichment analysis of the target genes were performed. The expression pattern of miR-206 in cattle tissues was detected by qPCR. The results showed that cattle miR-206 was most closely related to goat (Capra hircus), followed by horse (Equus caballus), and the most distantly related to Xenopus laevis. Among the potential target genes of miR-206 related to muscle development were histone deacetylase 4 (HDAC4), heat shock protein family D member 1 (HSPD1), and fibronectin (FN1). The functional enrichment analysis revealed that the predicted target genes were significantly enriched in MAPK, PI3K-AKT and TNF, which were signaling pathways related to muscle development. qPCR results showed that miR-206 expression was the highest in the leg and longest dorsal muscles of adult cattle and was extremely significant higher than that in other tissues (P<0.01), followed by liver, and the lowest was in the duodenum and subcutaneous. Compared with newborn calves, miR-206 expression was extremely significant down-regulated in subcutaneous fat and up-regulated in dorsal longest muscle and leg muscle (P<0.01) in adult cattle. The results of this study will provide a reference for further investigation of the role of miR-206 in the growth and development of cattle muscle.

Under hypoxic stress, transforming growth factors-β1 (TGF-β1)/Smad signaling pathway can be activated and caused the occurrence of hypoxic pulmonary hypertension by promoting the proliferation of pulmonary smooth muscle cells. In this study, qPCR was used to detect the relative expression levels of TGF-β1, Smad2 and Smad3 genes in the lung tissues of newborn, juvenile, adult and aged yak (Bos grunniens). The protein expression levels of TGF-β1, Smad2 and Smad3, the phosphorylated protein levels of Smad2/Smad3 (P-Smad2/Smad3) and their distribution characteristics in the lung tissues of newborn, juvenile, adult and aged yak were analyzed by Western blot and immunohistochemistry method. The results of qPCR and Western blot showed that the expression trends of TGF-β1, Smad2, Smad3 and P-Smad2/Smad3 were basically the same, and there were differences in expression in the lung tissue of yak in the newborn, juvenile, adult and aged groups, and the expression levels were higher in the lung tissue of the newborn and adult yak groups, which was significantly higher than that in the yak lung tissue of the juvenile and aged groups (P<0.05). The results of immunohistochemistry showed that the distribution of TGF-β1, Smad2, Smad3 and P-Smad2/Smad3 was basically the same, mainly distributed in tracheal epithelial cells, pulmonary artery endothelial cells and alveolar type Ⅱ epithelial cells in the lungs of newborn, juvenile, adult and aged yaks, the positive expression was also found in lung trachea wall smooth muscle cells and pulmonary artery smooth muscle cells in newborn, adult and aged yaks. This study found that TGF-β1/Smad signal pathway was activated during hypoxic adaptation in yak lungs, and there were significant differences in expression activity among newborn, juvenile, adult and aged yak lungs, the expression activity was higher in the newborn group, significantly down-regulated in the young group, the highest in the adult group, and decreased in the old group. These results showed that the dynamic regulation of TGF-β1/Smad signaling pathway could be involved in the formation of hypoxia adaptive structure and the maintenance of pulmonary vascular function in yaks. The results provide data for further study on the mechanism of lung hypoxia adaptation in yaks.

To assess the genetic diversity of local chicken (Gallus gallus) germplasm resources in Shandong province, and provide theoretical support and data reference for the management and innovative utilization, a total of 480 individuals from 6 Shandong local chicken breeds, 1 cultivated strain and 1 chicken breed outside the province were genotyped by 20 pairs of SSR primers in this study. Genetic diversity parameters, principal coordinate analysis (PCoA), and analysis of molecular variance (AMOVA) were generated using software. The results showed that a total of 226 alleles of 20 markers were detected with an average number of 11.3, PIC was 0.711. The mean allele of population was 6.625, the mean observed heterozygosity and expected heterozygosity were 0.579 and 0.666, respectively. AMOVA analysis showed that 18% of genetic variation was among the populations and 82% of genetic variation was within the populations, genetic variation mainly comes from different individuals within the population. PCoA and cluster analysis showed that 8 populations were divided into 3 genetic clusters, Jining Bairi chicken (JB), Laiwu Black chicken (LH), Luqin chicken (LQ), Langya chicken (LY), Luxi Mini chicken (LL) and Shouguang chicken (SG) were first clustered into one group, while Shiqi chicken (SQ) and Wenshang Barred chicken (WL) were clustered into one group separately. The study showed that there were very rich genetic diversity in 8 populations, the clustering results were consistent with the geographical distribution and relationship between each other. This study provides an important theoretical basis for the preservation, evaluation and utilization of local chickens in Shandong Province.

Interleukin-21 (IL-21) is a member of the common gamma chain (γc) cytokine family and plays an important role in defense against a variety of inflammatory and immune diseases. In order to explore the immune response function of IL-21 against pathogen infection, in this study, the ORF of largemouth bass (Micropterus salmoides) MsIL-21 (GenBank No. XP_038555572.1) was cloned, and bioinformatics and expression analysis were performed. The results showed that the full length of MsIL-21 ORF was 441 bp and encoding 146 amino acids. Sequence analysis revealed that MsIL-21 had the typical structure of IL-21 protein, including 4 groups of α-helices and 4 cysteine residues. Homology analysis revealed that MsIL-21 was most closely related to IL-21 of European sea bass (Dicentrarchus labrax). qPCR analysis showed that MsIL-21 was commonly expressed in all the healthy largemouth bass tissues tested, with the highest expression in the liver. After infection with Aeromonas veronii or Nocardia seriolae, the up-regulation of expression was detected in the liver, head kidney, and spleen. Similarly, after stimulation with pathogenic analogs lipopolysaccharide (LPS), lipoteichoic acid (LTA), and polyinosinic-polycytidylic acid [Poly(I:C)], the expression of MsIL-21 could be induced in head kidney leukocytes. The recombinant MsIL-21 protein was expressed and purified by prokaryotic expression system, which induced the expression of IL-10, IL-22, IL-1β, and interferon-γ (IFN-γ) in head kidney leukocytes. Taken together, the present study initially suggests that MsIL-21 may be involved in defense against pathogenic bacterial invasion and infection. This study further enriches the functional studies of fish IL-21.

Bacterial enteritis occurs frequently in aquaculture, however, the exact mechanism of bacterial enteritis was not well understood. This study aimed to identify novel candidate genes associated with Aeromonas hydrophila infection-induced enteritis. Barbel steed (Hemibarbus labeo) were infected with A. hydrophila, transcriptome sequencing of its intestine using the BGISEQ-500 platform. The results showed that a total of 120 173 unigenes were obtained by sequencing, with an average length of 1 328 bp and an N50 of 2 647 bp, of which 72.71% were known genes. Screening of differentially expressed genes (DEGs) found that there were 33 706 genes significantly differentially expressed after A. hydrophila infection, of which 18 878 unigenes were up-regulated, and 14 828 genes were down-regulated. Through GO enrichment analysis, DEGs were mainly enriched in cellular process, metabolic process, biological regulation, cell, cell part, and binding. The KEGG enrichment analysis showed that DEGs were mainly enriched in signal pathways such as signal transduction, immune system, cancers, infectious diseases, etc. According to DEGseq analysis and qPCR verification, it was found that the antimicrobial peptide genes, antimicrobial peptide genes (hepcidin and liver-expressed antimicrobial peptide 2 (leap2)) and inflammatory cytokine genes (interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), IL6 and IL8) were significantly increased after A. hydrophila infection. Meanwhile, the antibacterial activities of chemically synthesized Hepcidin, LEAP2 and NK-lysin against A. hydrophila were detected, and it was found that Hepcidin and LEAP2 could effectively inhibit the reproduction of A. hydrophila. This study provides basic data for further understanding of the pathogenic mechanism of bacterial enteritis in barbel steed and other farmed fish.

In recent years, the occurrence of wheat sharp eyespot has been increasing year by year, seriously affects food security. The prevention and control of wheat (Triticum aestivum) diseases in production mainly relies on chemical pesticides, but chemical control has many problems. In this paper, plate antagonism test, virulence assay and compatibility assay were used to preliminarily analyze the inhibition effect of fermentation broth of Bacillus subtilis Z-14 strain on the mycelial growth of Rhizoctonia cerealis, the virulence of pesticide Kuras on Rhizoctonia cerealis and the compatibility between Kuras and Z-14 strain. On this basis, the spore preparation of strain Z-14 (8.5×10⁷ CFU/mL) combined with pesticide Kuras seed dressing on wheat sharp blight control was studied. The results showed that Kuras had high virulence against Rhizoctonia cerealis, and its average concentration for 50% of maximal effect (EC₅₀) value of inhibiting the mycelial growth of Rhizoctonia cerealis was 0.035 μg/mL; At this concentration, there was no obvious inhibition on the growth of Z-14 bacteria, and it had good compatibility; The inhibition rate of Z-14 fermentation liquid on mycelia growth of wheat sharp eyespot was 86.57%. In greenhouse, the combined seed dressing of Z-14 spore preparation and Kuras had a control effect of 46.12% against sharp blight at the jointing stage of wheat, which was significantly higher than that of the single component. The combined use also promoted growth indicators such as root length, plant height, and stem thickness. Therefore, the use of biological agents to control wheat diseases is effective, it is of great significance for promoting the green development of agriculture.

Soil microorganism is one of the indexes to evaluate soil quality in saline-alkali land, and the application of microbial agent is an important measure to improve soil microenvironment. In this study, two treatments were set: control PC (no fertilization) and P2 (saline-alkali soil remediation agent). The saline-alkali soil remediation agent containing Bacillus flexus and Bacillus megaterium were used as test materials. The physical and chemical properties of the rhizosphere soil and the number of culturable microorganisms were determined by conventional methods, and the population structure and diversity of soil microorganisms were determined by high-throughput sequencing technology. The research results showed that the number of culturable bacteria increased by 126.5% and the number of fungi decreased by 27.02%. High-throughput sequencing analysis of 16S rRNA and ITS fragments in the rhizosphere soil showed that the microorganisms in the rhizosphere of dandelion included 418 species of bacteria (26 phyla, 74 genera) and 371 species of fungi (10 phyla, 30 genera). In terms of community structure, the application of P2 increased the relative abundance of Acidobacteria, Ascomycota, Rozellomycota and Mortierellomycota. But the relative abundance of Proteobacteria, Gemmatimonadetes, Chloroflexi and Basidiomycota was decreased. Principal component analysis (PCA) showed that application of fungicides changed the microbial community structure in dandelion rhizosphere soil. Redundancy analysis (RDA) showed that soil organic matter and available phosphorus were the main environmental factors which affected soil microbial community of dandelion rhizosphere. Soil remediation agents improved soil microbial diversity and improved soil microenvironment of dandelion rhizosphere. This study provides the references for planting dandelion in coastal saline alkali land in North China.

At present, the demand for meat products has increased because of the rapid growth of the population. The livestock system raises a number of environmental and ethical issues. Therefore, the research of artificial meat will have an important impact on the supply of meat products in the future. Artificial meat includes cultured meat and plant protein meat. Among them, cultured meat is the best alternative to conventional meat. However, large-scale production of cultured meat still faces many challenges due to technical difficulties and high costs. In this review, the development process and current technical challenges of cultured meat are introduced, including the selection of cell types for initial culture, factors and regulatory methods which restrict cell proliferation and differentiation, cell culture environment optimization and muscle tissue formation in vitro. This review provides reference for the industrial production of cultured meat.

Retinoic acid, an active metabolite of vitamin A, is the essential exogenous signal during spermatogenesis. However, the role and regulatory mechanism of retinoic acid signaling in spermatogenesis are not clear. In this review, the generation, transduction, receiving and remove of retinoic acid signal and downstream genes regulated by retinoic acid during spermatogenesis were summarized, which would not only provide some references for the further study of the regulation mechanism of retinoic acid signal in spermatogenesis, but also lay a theoretical foundation for ensuring and improving the fecundity of livestock.

Intensive farming increased the risk of bacterial disease outbreaks in aquacultural fish. Researches on the intestines and their microflora, which is the important immune barrier of aquatic animals, are considered to be an effective way of solutions. Numbers of studies showed that lactic acid bacteria (LAB) were gram-positive and non-sporing bacteria that commonly colonized in aquacultural animal intestines as probiotics. In this paper, regulation of LAB in intestinal microflora structure in fish, nutrients digestion and absorption improvement of LAB in fish intestines, activation of intestinal mucosal immunity, the adsorption and degradation of toxins in fish intestines were reviewed. This review provides a theoretical basis for the study of LAB in fish.

Transferrin receptor (TfR) is a type Ⅱ transmembrane dimer glycoprotein located on the cell membrane, which is the receptor for the invasion of dog (Canis lupus familiaris), cat (Felinae) and other Carnivorous parvovirus into host cells. This study aimed to establish a TaqMan real-time fluorescent quantitative PCR assay for detecting the expression of TfR in carnivore, and to detect and analyze the expression of TfR gene in different tissues of carnivores and passage cells. A pair of primers and a specific TaqMan probe were designed and synthesized by referencing to the gene sequence of the TfR extracellular region protein published in GenBank. The reaction system and conditions of qPCR were optimized, a positive plasmid was constructed, a standard curve was established, and the sensitivity and repeatability test were carried out. The expression of TfR gene in different tissues of carnivores and passage cells were detected and analyzed by the established method. The results showed that the assay had a good linear relationship, sensitivity and stability with a correlation coefficient of 0.998 7, the detection limit was 67 copies/μL, the coefficient of variation of intra-assay and inter-assay evaluation test was less than 2.0%. This study provides a qPCR method for detecting the expression of TfR gene in carnivore with good sensitivity and stability, and it can be used for detecting the expression of TfR gene in different tissues and passage cells of carnivore.

With the development and progress of the pig industry in China, higher expection are required for the differential diagnosis and big data analysis of diseases. Here, a novel method was established, which promoted the development and application of high-throughput detection technology in animal pathogen detection. In detail, specific primers and probes were designed for the Pseudorabies virus (PRV)、Japanese encephalitis virus (JEV)、Classical swine fever virus (CSFV)、Porcine circovirus type 2 (PCV-2)、Porcine reproductive and respiratory syndrome virus (PRRSV)、Porcine parvovirus (PPV)、African classical swine fever virus (ASFV) 7 pathogens of swine (Sus scrofa) reproductive diseases. After optimizing the reaction conditions, coupling the probe with microspheres, and hybridization capture reaction, a liquid chip detection method to detect 7 pig reproductive diseases at the same time was successfully established and applied to clinical practice. The results showed that the specific target gene could be captured and detected in the liquid environment, the detection limit of 7 specific pathogens was 10³ copies/μL. The method had good specificity and no cross reaction with other pathogens. The established method was used to detect the 65 samples collected from large-scale pig farms in Sichuan province. A total of 49 positive samples were detected, with a positive rate of 75.38% (49/65). The positive rate of mixed infection of 2 or more pathogens was 23.08% (15/65). The results of single PCR detection were consistent with the established method, which confirmed that the established liquid chip detection method can be applied to clinical detection. This study provides a powerful technical reserve for rapid differential diagnosis of multiple pathogens of swine disease, and provides a reference for the further development of high-throughput detection technology.

Pasteurella multocida toxin (PMT), as one of the most important virulence factors of Pasteurella multocida, endangers the health of pigs and causes huge economic losses. To identify the toxicity of recombinant Pasteurella multocida toxin (rPMT) against 4 kinds of porcine cells, and construct the pathological model of toxicity against Mus musculus. pCold Ⅰ-toxA vector was constructed and rPMT was soluble expressed. Morphological observation, cell counting kit-8 (CCK-8) detection and Propidium Iodide (PI) staining were used to explore the toxicity of rPMT against PK15 and other 3 kinds of porcine cells. The median lethal dose (LD₅₀) of rPMT to C57BL/6J mice was determined by Karber method, and the histopathological analysis of heart, liver, spleen, lung, kidney and small intestine was carried out. The results showed that rPMT protein (146 kD) was successfully expressed; After treated with rPMT, PK15 cells arose obvious pathological changes, more cells died and cell activity decreased significantly (P<0.05) among the 4 kinds of porcine cell, but the activity of IPEC cells increased significantly (P<0.05); The LD₅₀ of rPMT against C57BL/6J mice was 0.490 ng/g; After the challenge, the intestinal villi of mice fell off; the congestion of kidney and liver was serious; the splenic sinus, which is in the red pulp area of spleen, bled; The number of lymphocytes decreased and a large number of pigments deposited. This study finds that the toxic effect of rPMT against PK15 was the most significant among the 4 kinds of porcine cells; The cytotoxicity model of rPMT against PK15 was successfully constructed and the pathological model of toxicity aginst C57BL/6J mice was successfully constructed, which provides a theoretical basis for further study of the pathogenic mechanism of PMT.