Characterization and expression analysis of Wnt5 in Schistosoma japonicum at different developmental stages.

Wnt signaling is a key pathway involving the regulation of cell development and growth in metazoa. An analysis of Wnt signaling in Schistosoma japonicum might provide information regarding the molecular mechanisms underlying parasite development, which might be useful for vaccine screening and identification of pharmaceutical targets. The SjWnt5 gene, a member of the Wnt gene family, contained an 1149-bp open reading frame that encoded a 382-aa protein. Analysis of the SjWnt5 amino acid sequence revealed a domain that was conserved among members of the Wnt protein family. Expression of SjWnt5 was observed at all of the developmental stages in definitive hosts, and the highest level of SjWnt5 messenger RNA (mRNA) was detected at the schistosomula stage. Higher levels of SjWnt5 mRNA and protein were observed in mature male worms, compared with those in mature females. SjWnt5 mRNA was expressed at higher levels in maldeveloped worms from nonpermissive host or single-sex infection than in normal worms from permissive host and mixed-sex infection. The immunohistochemical analysis showed that SjWnt5 protein was expressed in the subtegumental musculature and acetabulum musculature of schistosomulum and adult worms, suggesting that SjWnt5 may play a role in regulation of parasite muscle development. Furthermore, SjWnt5 was found prominently expressed in the testes of the male and the ovary as well as the vitellarium of the female, suggesting that SjWnt5 may involve in the development of the reproductive organs of both sexes.

Cross-border regulation of the STK39/MAPK14 pathway by Lycium barbarum miR166a to inhibit triple-negative breast cancer.

OBJECTIVE: To investigate the effects of Lycium barbarum miRNA166a (Lb-miR166a) on human gene expression regulation during the therapy for triple-negative breast cancer (TNBC). METHODS: Transcriptome sequencing was used to analyze the distribution and composition of miRNA in Lycium barbarum fruit. Lb-miR166a was introduced into TNBC MB-231 cells by lentiviral transfection to study its effects on cell proliferation, apoptosis, invasion, and metastasis both in vivo and in vitro. Bioinformatic and dual-luciferase assays identified the target gene of Lb-miR166a. The role of STK39 in TNBC progression was elucidated through clinical data analysis combined with cellular studies. The influence of Lb-miR166a on the STK39/MAPK14 pathway was confirmed using a target-specific knockout MB-231 cell line. RESULTS: Lb-miR166a was found to be highly expressed in Lycium barbarum. It inhibited MB-231 cell proliferation, invasion, and metastasis, and promoted apoptosis. STK39 was overexpressed in TNBC and was associated with increased invasiveness and poorer patient prognosis. Gene enrichment analysis and dual-luciferase assays demonstrated that Lb-miR166a regulates STK39 expression cross-border and inhibits MAPK14 phosphorylation, impacting the phosphorylation of downstream target genes. CONCLUSION: The downregulation of STK39 and subsequent inhibition of MAPK14 phosphorylation by Lb-miR166a leads to reduced proliferation, migration, and invasion of TNBC cells. These findings suggest a novel therapeutic strategy for TNBC treatment, highlighting possible clinical applications of Lb-miR166a in managing this aggressive cancer type.

Generation and characterization of chimeric Tembusu viruses containing pre-membrane and envelope genes of Japanese encephalitis virus.

Since its outbreak in 2010, Tembusu virus (TMUV) has spread widely throughout China and Southeast Asia, causing significant economic losses to the poultry industry. In 2018, an attenuated vaccine called FX2010-180P (180P) was licensed for use in China. The 180P vaccine has demonstrated its immunogenicity and safety in mice and ducks. The potential use of 180P as a backbone for flavivirus vaccine development was explored by replacing the pre-membrane (prM) and envelope (E) genes of the 180P vaccine strain with those of Japanese encephalitis virus (JEV). Two chimeric viruses, 180P/JEV-prM-E and 180P/JEV-prM-ES156P with an additional E protein S156P mutation were successfully rescued and characterized. Growth kinetics studies showed that the two chimeric viruses replicated to similar titers as the parental 180P virus in cells. Animal studies also revealed that the virulence and neuroinvasiveness of the 180P/JEV-prM-E chimeric virus was decreased in mice inoculated intracerebrally (i.c.) and intranasally (i.n.), respectively, compared to the wild-type JEV strain. However, the chimeric 180P/JEV-prM-E virus was still more virulent than the parent 180P vaccine in mice. Additionally, the introduction of a single ES156P mutation in the chimeric virus 180P/JEV-prM-ES156P further attenuated the virus, which provided complete protection against challenge with a virulent JEV strain in the mouse model. These results indicated that the FX2010-180P could be used as a promising backbone for flavivirus vaccine development.

326K at E Protein Is Critical for Mammalian Adaption of TMUV.

Outbreaks of Tembusu virus (TMUV) infection have caused huge economic losses to the poultry industry in China since 2010. However, the potential threat of TMUV to mammals has not been well studied. In this study, a TMUV HB strain isolated from diseased ducks showed high virulence in BALB/c mice inoculated intranasally compared with the reference duck TMUV strain. Further studies revealed that the olfactory epithelium is one pathway for the TMUV HB strain to invade the central nervous system of mice. Genetic analysis revealed that the TMUV HB virus contains two unique residues in E and NS3 proteins (326K and 519T) compared with duck TMUV reference strains. K326E substitution weakens the neuroinvasiveness and neurovirulence of TMUV HB in mice. Remarkably, the TMUV HB strain induced significantly higher levels of IL-1ß, IL-6, IL-8, and interferon (IFN)-α/ß than mutant virus with K326E substitution in the brain tissue of the infected mice, which suggested that TMUV HB caused more severe inflammation in the mouse brains. Moreover, application of IFN-ß to infected mouse brain exacerbated the disease, indicating that overstimulated IFN response in the brain is harmful to mice upon TMUV infection. Further studies showed that TMUV HB upregulated RIG-I and IRF7 more significantly than mutant virus containing the K326E mutation in mouse brain, which suggested that HB stimulated the IFN response through the RIG-I-IRF7 pathway. Our findings provide insights into the pathogenesis and potential risk of TMUV to mammals.

Comparison of worm development and host immune responses in natural hosts of Schistosoma japonicum, yellow cattle and water buffalo.

BACKGROUND: Yellow cattle and water buffalo are two of the most important natural hosts for Schistosoma japonicum in China. Previous observation has revealed that yellow cattle are more suited to the development of S. japonicum than water buffalo. Understanding more about the molecular mechanisms involved in worm development, as well as the pathological and immunological differences between yellow cattle and water buffalo post infection with S japonicum will provide useful information for the vaccine design and its delivery procedure. RESULTS: The worm length (p < 0.01), worm recovery rate (p < 0.01) and the percentage of paired worms (p < 0.01) were significantly greater in yellow cattle than those in water buffalo. There were many white egg granulomas in the livers of yellow cattle, but fewer were observed in water buffalo at 7 weeks post infection. The livers of infected yellow cattle contained significantly increased accumulation of inflammatory cells, and the schistosome eggs were surrounded with large amounts of eosinophil infiltration. In contrast, no hepatocyte swelling or lymphocyte infiltration, and fewer white blood cells, was observed in water buffalo. The percentage of CD4⁺ T cells was higher in yellow cattle, while the percentage of CD8⁺ T cells was higher in water buffalo from pre-infection to 7 w post infection. The CD4/CD8 ratios were decreased in both species after challenge with schistosomes. Comparing with water buffalo, the IFN-γ level was higher and decreased significantly, while the IL-4 level was lower and increased gradually in yellow cattle from pre-infection to 7 w post infection. CONCLUSIONS: In this study, we confirmed that yellow cattle were more suited to the development of S. japonicum than water buffalo, and more serious pathological damage was observed in infected yellow cattle. Immunological analysis suggested that CD4⁺ T cells might be an integral component of the immune response and might associate with worm development in yellow cattle. A shift from Th1 to Th2 type polarized immunity was only shown clearly in schistosome-infected yellow cattle, but no shift in water buffalo. The results provide valuable information for increased understanding of host-schistosome interactions, and for control of schistosomiasis.

Biological Characteristics of Infectious Laryngotracheitis Viruses Isolated in China.

Infectious laryngotracheitis virus (ILTV) causes severe respiratory disease in chickens and results in huge economic losses in the poultry industry worldwide. To correlate the genomic difference with the replication and pathogenicity, phenotypes of three ILTVs isolated from chickens in China from 2016 to 2018 were sequenced by high-throughput sequencing. Based on the entire genome, the isolates GD2018 and SH2017 shared 99.9% nucleotide homology, while the isolate SH2016 shared 99.7% nucleotide homology with GD2018 and SH2017, respectively. Each virus genome contained 82 ORFs encoding 77 kinds of protein, 31 of which share the same amino acid sequence in the three viruses. GD2018 and SH2017 shared 57 proteins with the same amino acid sequence, while SH2016 shared 42 and 41 proteins with the amino acid sequences of GD2018 and SH2017, respectively. SH2016 propagated efficiently in allantoic fluid and on chorioallantoic membranes (CAMs) of SPF chicken embryo eggs, while GD2018 and SH2017 proliferated well only on CAMs. GD2018 propagated most efficiently on CAMs and LMH cells among three isolates. SH2016 caused serious clinical symptoms, while GD2018 and SH2017 caused mild and moderate clinical symptoms in chickens, although the sero of the chickens infected with those three isolates were all positive for anti-ILTV antibody at 14 and 21 days after challenge. Three ILTVs with high genetic homology showed significant differences in the replication in different culture systems and the pathogenicity of chickens, providing basic materials for studying the key determinants of pathogenicity of ILTV.

An Emerging Duck Egg-Reducing Syndrome Caused by a Novel Picornavirus Containing Seven Putative 2A Peptides.

Since 2016, frequent outbreaks of egg-reducing syndromes caused by an unknown virus in duck farms have resulted in huge economic losses in China. The causative virus was isolated and identified as a novel species in Avihepatovirus of the picornavirus family according to the current guidelines of the International Committee on Taxonomy of Viruses (ICVT), and was named the duck egg-reducing syndrome virus (DERSV). The DERSV was most closely related to wild duck avihepatovirus-like virus (WDALV) with 64.0%, 76.8%, 77.5%, and 70.7% of amino acid identities of P1, 2C, 3C, and 3D proteins, respectively. The DERSV had a typical picornavirus-like genomic structure, but with the longest 2A region in the reported picornaviruses so far. Importantly, the clinical symptoms were successfully observed by artificially infecting ducks with DERSV, even in the contact exposed ducks, which suggested that DERSV transmitted among ducks by direct contact. The antibody levels of DERSV were correlated with the emergence of the egg-reducing syndromes in ducks in field. These results indicate that DERSV is a novel emerging picornavirus causing egg-reducing syndrome in ducks.

The emergence of a disease caused by a mosquito origin Cluster 3.2 Tembusu virus in chickens in China.

In 2021, a chicken Tembusu virus (TMUV) caused outbreaks of a disease characterized by retarded growth and egg production decline in chickens in China. Two TMUV strains SD2021 and GX2021 were isolated from the diseased chickens and phylogenetic analysis of the E gene nucleotide sequence revealed that the chicken TMUV SD2021 and GX2021 were most close to mosquito origin TMUV in Cluster 3.2, which was distinct from the prevalent duck TMUVs in Cluster 2. The TMUV SD2021 caused growth retardation and neurological symptoms in chickens through both intranasal and intramuscular infection routes, but has no direct-contact transmissibility among chickens. The findings of this study highlight the pathogenicity of a chicken adapted mosquito-origin TMUV in chickens in China.

Molecular cloning and functional characterization of Schistosoma japonicum enolase which is highly expressed at the schistosomulum stage.

Enolase is a key enzyme in the glycolytic pathway; recent studies have also shown that enolase is found on the surface of several parasites, where it acts as a plasminogen-binding protein. In the present study, the enolase of Schistosoma japonicum has been cloned and expressed. In western blot analysis, the recombinant enolase from S. japonicum ( rSjENO) was recognized by rabbit sera directed against an antigen preparation from adult worms. Kinetic measurement revealed that rSjENO possesses good enzymatic activity. The real-time PCR showed that the enolase gene was highly expressed at 18-28 days of the life cycle. Immunofluorescence testing showed that SjENO was located mainly on the surface as well as in the inner tissues of the worms. Ligand-blotting analysis indicated that rSjENO could bind to human plasminogen as its receptor. In addition, a 24.28% reduction in the liver egg count and a reduction of 21.45% in the fecal egg count were observed in BALB/c mice vaccinated with rSjENO when compared with blank control mice. An ELISA assay suggested that high levels of specific IgG antibody could be induced by rSjENO in vaccinated mice.

Wnt4, the first member of the Wnt family identified in Schistosoma japonicum, regulates worm development by the canonical pathway.

The Wnt signaling pathway is an evolutionarily conserved signal transduction pathway used extensively during animal development. We aim, by increasing our understanding of the Wnt signaling pathway, to find a key gene or protein present in schistosomes that can be developed into vaccine candidate or drug target. We therefore isolated the Wnt4 gene from Schistosoma japonicum. Wnt4 encodes a putative protein of 558 amino acids which contains the conserved functional domain of the Wnt gene family. We suppressed the expression of Wnt4 mRNA in 10-day schistosomulae by RNA interference. Quantitative PCR analysis showed that Wnt4 displayed a 73% reduction in the transcript level. And GSK-3beta and beta-catenin, which are involved in Wnt canonical pathway, showed a 45% and 39% reduction in mRNA levels, respectively. PLC, CaMKII, DVL, and JNK, which are involved in Wnt non-canonical pathway, showed no reduction. These results suggest that the Wnt4 signal protein in S. japonicum regulates downstream genes by a canonical pathway. Wnt4 is the first member of the Wnt family to be identified in S. japonicum. An increased understanding of the Wnt signal transduction pathway will allow us to elucidate further the molecular mechanism of development in schistosomes.

Analysis of genome-wide SNPs based on 2b-RAD sequencing of pooled samples reveals signature of selection in different populations of Haemonchus contortus.

The parasitic nematode Haemonchus contortus is one of the world's most important parasites of small ruminants that causes significant economic losses to the livestock sector. The population structure and selection in its various strains are poorly understood. No study so far compared its different populations using genome-wide data. Here, we focused on different geographic populations of H. contours from China (Tibet, TB; Hubei, HB; Inner Mongolia, IM; Sichuan, SC), UK and Australia (AS), using genome-wide population-genomic approaches, to explore genetic diversity, population structure and selection. We first performed next-generation high-throughput 2b RAD pool sequencing using Illumina technology, and identified single-nucleotide polymorphisms (SNPs) in all the strains. We identified 75,187 SNPs for TB, 82,271 for HB, 82,420 for IM, 79,803 for SC, 83,504 for AS and 78,747 for UK strain. The SNPs revealed low-nucleotide diversity (pi= 0.0092-0.0133) within each strain, and a significant differentiation level (average Fst = 0.34264) among them. Chinese populations TB and SC, along with the UK strain, were more divergent populations. Chinese populations IM and HB showed affinities to the Australian strain. We then analysed signature of selection and detected 44 (UK) and 03 (AS) private selective sweeps containing 49 and 05 genes, respectively. Finally, we performed the functional annotation of selective sweeps and proposed biological significance to signature of selection. Our data suggest that 2b-RAD pool sequencing can be used to assess the signature of selection in H. contortus.

Microsatellite analysis reveals extensive gene flow, and lack of population structure in the farm populations of Haemonchus contortus in northern China.

The parasitic nematode Haemonchus contortus is economically an important parasite of small ruminants across the globe. China is the world's largest producer, consumer, and importer of mutton. With ubiquitous distribution across the country H. contortus is one of the potential candidates to cause huge economic losses to small ruminant farming industry in China. We herein investigated genetic diversity and population structure of six farm populations of H. contortus in northern China, and also compared them to H. contortus isolates from UK and Australia. We first prepared individual DNA samples from 240 adult worms, and generated genotyping data using eight microsatellite markers. Obtained data was then subjected to allelic frequency and population genetic analyses. The overall allelic richness (mean/locus/pop = 7.375 ±â€¯0.844-10.125 ±â€¯1.109), and expected heterozygosity (mean/locus/pop = 0.646 ±â€¯0.040-0.735 ±â€¯0.025) indicated high degree of population genetic variation across the Chinese isolates. Low level of genetic differentiation (Fst = 0.010-0.066) was observed across all the populations. AMOVA results showed high level of variation (93%) within the populations. PCA analysis revealed mixed clustering of all the populations with no visible geographical sub-structuring. Finally the population admixture analysis resulted in extensive admixing of genotypes across all the populations. With these findings we conclude that there is no obvious population genetic structure with extensive gene flow across all the farm populations of H. contortus in northern China.

Spatiotemporal expression pattern of Sjfz7 and its expression comparison with other frizzled family genes in developmental stages of Schistosoma japonicum.

Wnts are secreted signaling molecules that are implicated in a variety of growth-related processes. Frizzled proteins have been identified as receptors for Wnt ligands in vertebrates and invertebrates, but a functional role for dioecious flatworm Frizzleds has not been determined. To evaluate the endogenous role of Frizzled proteins during development, we have identified and characterized a Schistosoma japonicum frizzled gene (Sjfz7). We found that Sjfz7 encodes a 698 amino acid protein with typical characteristics of Frizzled proteins. The immunohistochemical localization pattern showed that Sjfz7 protein was extensively distributed in almost all tissues of S. japonicum, including subtegumental muscle cells, parenchymal cells, intestinal epithelial cells and male and female germ cells. This indicated that Sjfz7-mediated Wnt signaling might be associated with the development of musculature, intestinal tract and reproductive organs in schistosome. Comparing mRNA levels between frizzled family members showed that Sjfz7 mRNA was consistently higher in the developmental stages analyzed, suggesting that Sjfz7 may be responsible for more functional tasks than other frizzled family members. Comparing frizzled mRNA levels between not fully developed and normal worms suggested that Wnt signaling might be abnormal in not fully developed worms.

[Application of reverse vaccinology in Schistosoma vaccine development: advances and prospects].

OBJECTIVE: Current advances in reverse vaccinology based on the principle of "sequence-structure-function" and such integrated platform technologies as immunoinformatics, computer-aid design, and various high-throughput omics (including genomics, transcriptomics and proteomics) may pave a new way for the discovery of candidate vaccine molecules against schistosomiasis. Both theoretical prediction and experimental approaches conventionally used in the field of reverse vaccinology are briefly introduced in this review; and the applications of these approaches to screening and confirming candidate Schistosoma vaccine molecules are also summarized. Furthermore, potential research prospects of the application of reverse vaccinology to Schistosoma vaccine development are discussed by simulating immune effect mechanisms of immunization with radiation-attenuated cercaria vaccine in animal hosts and naturally acquired immunity in human population.

[Construction of phage display cDNA library from adult worms of Schistosoma japonicum].

OBJECTIVE: To screen protective antigen genes and construct the T7 phage display library from adult worms of Schistosoma japonicum. METHODS: Total RNA was extracted from adult worms of S. japonicum by Trizol reagent anti mRNA was isolated from the total RNA. The ds cDNA was synthesized by reverse transcription using random primer. Directional EcoR I/ Hind III linkers were ligated into the ends of ds cDNA and the ds cDNA was digested with EcoR I anti Hind III, which resulted in ds cDNA with EcoR I and Hind III adhering ends. The digested ds cDNA fragments longer than 300 bp in length were fractionated and ligated into T7 Select 10-3b vector. After packaging in citro, the T7 Select 10-3b vector was transformed into BLT5403 to construct the T7 phage display cDNA library. Plaque assay and PCR were used to evaluate the library. Seven known objective genes of S. japonicum were screened by PCR to detect the representation of the library. RESULT: Primary library capacity was 4.98 x 10(6) pfu, and the titer of amplified library was 3.85 x 10(11) pfu/mL. The PCR identification result of 96 clones picked at random showed that recombination rate was 93.8%, in which 95.6% inserted cDNA fragments were longer than 300 bp in length. All the seven known objective genes of S. japonicum were amplified from the library. CONCLUSION: The T7 phage display library from adult worms of Schistosoma japonicum was constructed.

SjCRT, a recombinant Schistosoma japonicum calreticulin, induces maturation of dendritic cells and a Th1-polarized immune response in mice.

BACKGROUND: It is well known that immunization of radiation-attenuated (RA) schistosoma cercariae or schistosomula can induce high levels of protective immunity against schistosoma cercariae reinfection in many animals. Many studies have shown that the Th1 cellular immune response is crucial for the protective effect elicited by RA schistosomula. However, the molecular mechanism of this strong protective immunity remains unclear. METHODS: The expression profiles of Schistosoma japonicum calreticulin (SjCRT) in RA and normal schistosoma-derived cells were investigated by flow cytometry. The effect of recombinant SjCRT (rSjCRT) on mouse dendritic cells (DCs) was determined by FACS, ELISA and RT-PCR analysis. We also analyzed the effects of SjCRT on the activation of spleen cells from mice immunized with rSjCRT by detecting lymphocyte proliferation and the cytokine profiles of splenocytes. RESULTS: We found that the expression level of SjCRT in the cells from RA larvae was significantly higher than that in cells from normal schistosomula at early stages of development (day 4). The results of effect of rSjCRT on mouse DCs showed that rSjCRT could induce phenotypic and functional maturation of DCs, and SjCRT bound to the surface of DCs through the CD91 receptor and could be engulfed by DCs. The results of activation of splenocytes from mice immunized with rSjCRT also demonstrate that rSjCRT can effectively stimulate the proliferative response of splenic lymphocytes, elicit splenocytes from immunized mice to secrete high levels of IFN-γ, TNF-α and IL-4, and activate CD4+ T cells to produce high levels of IFN-γ. CONCLUSION: SjCRT is one of the immunostimulatory molecules released from RA schistosomula cells, might play a crucial role in conferring a Th1-polarized immune response induced by RA cercariae/schistosomula in mice, and is a candidate molecule responsible for the high levels of protective immunity induced by RA schistosomula.

Genome-wide SNP analysis using 2b-RAD sequencing identifies the candidate genes putatively associated with resistance to ivermectin in Haemonchus contortus.

BACKGROUND: The excessive and uncontrolled use of anthelmintics, e.g. ivermectin (IVM) for the treatment of livestock parasites has led to widespread resistance in gastrointestinal nematodes, such as Haemonchus contortus. There is an urgent need for better management of drug-use in nematode control and development of novel anthelmintics. Discovery and identification of anthelmintic resistance-associate molecules/markers can provide a basis for rational anthelmintics-use and development of novel drugs. Recent studies have shown that ivermectin resistance in H. contortus is likely to be multi-genic in nature except for several genes coding for IVM target and efflux pump. However, no other IVM resistance-associated genes were characterized by conventional methods or strategies. In the present study we adopted a new strategy, i.e. using genome-wide single nucleotide polymorphism (SNP) analysis based on 2b-RAD sequencing, for discovering SNPs markers across the genomes in both IVM susceptible and resistant isolates of H. contortus and identifying potential IVM resistance-associated genes. RESULTS: We discovered 2962 and 2667 SNPs within both susceptible and resistant strains of H. contortus, respectively. A relative lower and similar genetic variations were observed within both resistant and susceptible strains (average π values were equal to 0.1883 and 0.1953, respectively); whereas a high genetic variation was found across both strains (average π value was equal to 0.3899). A significant differentiation across 2b-RAD tags nucleotide sites was also observed between the two strains (average FST value was equal to 0.3076); the larger differences in average FST were observed at SNPs loci between coding and noncoding (including intronic) regions. Comparison between resistant and susceptible strains revealed that 208 SNPs loci exhibited significantly elevated FST values, 24 SNPs of those loci were located in the CDS regions of the nine genes and were likely to have signature of IVM directional selection. Seven of the nine candidate genes were predicted to code for some functional proteins such as potential IVM target and/or efflux pump proteins, component proteins of receptor complex in membrane on neuromuscular cells, and transcriptional regulation proteins. Those genes might be involved in resistance to IVM. CONCLUSIONS: Our data suggest that candidate genes putatively associated with resistance to IVM in H. contortus may be identified by genome-wide SNP analysis using 2b-RAD sequencing.

Characterization and expression pattern of a novel Frizzled 8 receptor gene in Schistosoma japonicum.

Wnt signaling as mediated by the Frizzled family receptors plays a vital role in the early development of animal embryos, organ formation, tissue regeneration and other physiological processes. In the present study, a novel Frizzled member, SjFz8, was isolated and characterized in Schistosoma japonicum. SjFz8 encodes an 1162-amino-acid protein with typical characteristics of Frizzled proteins. Quantitative real-time polymerase chain reaction analysis indicated that SjFz8 transcript level was highest in 7-day-old schistosomula. In adult stages, SjFz8 mRNA expression remained at a low level after male-female pairing. The immunohistochemical localization of the Fz8 protein revealed that it existed in almost all tissues of S. japonicum, including subtegumental muscle, parenchyma, oral suckers, ventral suckers, testes of the male and ovaries of the female. We speculated that the Wnt signaling pathway that was mediated by Fz8 might take part in regulating histogenesis and organogenesis during the schistosomulum period, and play an important role in regulating further growth and development of male and female worms.

Proteome-wide analysis of lysine acetylation in adult Schistosoma japonicum worm.

UNLABELLED: Lysine acetylation, a ubiquitous and conserved posttranslational modification, has recently been shown to participate in many diverse non-chromatin-associated biological processes in prokaryotes and eukaryotes. However, the full extent and functional significance of acetylation in Schistosoma japonicum is still unknown. To investigate the nature, extent, and biological functions of lysine acetylation in schistosomes, immunoaffinity-based acetyl-lysine peptide enrichment, integrated with mass spectrometry, was used to comprehensively characterize the lysine-acetylated proteins in this parasite. In total, 1109 acetylated proteins and 2393 acetylation sites in S. japonicum were identified, representing the largest acetylome yet reported in a parasite. In a bioinformatic analysis showed that these acetylated proteins were mainly enriched in the biological process categories of metabolism, gene expression, translation, and transport. The classification according to molecular function revealed that the largest class involved the catalytic activity of different enzymes, including oxidoreductase, transferase, and pyrophosphatase activities. Most of the acetylated proteins in the cellular component category occurred in the cytoplasm, membrane, cytoskeleton, and nucleus. These data demonstrate the generality of lysine acetylation and provide the first global survey of acetylation in schistosomes. Our findings are an exciting starting point for the further exploration of the functions of acetylation in the biology of this parasite. SIGNIFICANCE: Schistosomiasis is one of the world's most prevalent and neglected tropical parasitic zoonotic diseases, and it causes almost 200,000 deaths annually. To control and eradicate schistosomiasis, effective vaccines are urgently required, and drug targets that are essential for schistosome survival must be identified in fundamental studies of schistosome biology. Posttranslational modifications are complex, fundamental, and important mechanisms that regulate the physiological functions of organisms. Lysine acetylation, a ubiquitous and conserved posttranslational modification, has recently been shown to participate in many diverse non-chromatin-associated biological processes in prokaryotes and eukaryotes. However, the full extent and functional significance of acetylation in Schistosoma japonicum is still unknown. To investigate the nature, extent, and biological functions of lysine acetylation in S. japonicum, we employ immunoaffinity-based acetyl-lysine peptide enrichment, integrated with mass spectrometry to comprehensively characterize the lysine-acetylated proteins in this parasite. The results of our data demonstrate the generality of lysine acetylation and provide the first global survey of acetylation in schistosomes. Our findings are an exciting starting point for the further exploration of the functions of acetylation in the biology of this parasite. Meanwhile, identifying the mechanisms and proteins targeted by acetylation may also provide a promising avenue for specific drug design and the development of sophisticated therapeutic strategies.

The Differential Expression of Immune Genes between Water Buffalo and Yellow Cattle Determines Species-Specific Susceptibility to Schistosoma japonicum Infection.

Water buffalo are less susceptible to Schistosoma japonicum infection than yellow cattle. The factors that affect such differences in susceptibility remain unknown. A Bos taurus genome-wide gene chip was used to analyze gene expression profiles in the peripheral blood of water buffalo and yellow cattle pre- and post-infection with S. japonicum. This study showed that most of the identified differentially expressed genes (DEGs) between water buffalo and yellow cattle pre- and post-infection were involved in immune-related processes, and the expression level of immune genes was lower in water buffalo. The unique DEGs (390) in yellow cattle were mainly associated with inflammation pathways, while the unique DEGs (2,114) in water buffalo were mainly associated with immune-related factors. The 83 common DEGs may be the essential response genes during S. japonicum infection, the highest two gene ontology (GO) functions were associated with the regulation of fibrinolysis. The pathway enrichment analysis showed that the DEGs constituted similar immune-related pathways pre- and post-infection between the two hosts. This first analysis of the transcriptional profiles of natural hosts has enabled us to gain new insights into the mechanisms that govern their susceptibility or resistance to S. japonicum infections.