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ABSTRACT: Eimeria tenella, an obligate intracellular apicomplexan parasite, is the major causative agent of chicken coccidiosis. Some epidermal growth factor (EGF)-like domain-containing proteins of other members of apicomplexan parasites have been reported to contribute to parasite survival. To date, however, EGF-like domain-containing proteins of E. tenella are not well studied. In this study, a gene fragment that encodes 4 EGF-like domains of E. tenella microneme protein 7 (EGF-EtMIC7) was amplified and expressed using an Escherichia coli expression system. Following generation of polyclonal antibodies that recognize recombinant EGF-EtMIC7 (rEGF-EtMIC7), the expression of EtMIC7 in sporozoites and merozoites was examined. Moreover, its roles in cellular regulation were investigated. The native EtMIC7 in E. tenella sporozoites and merozoites was detected by using Western blot and indirect immunofluorescence assays. rEGF-EtMIC7 could activate Akt, whereas blockade of EGF receptor (EGFR) failed to induce Akt phosphorylation. Compared with the control group, LMH cells treated with rEGF-EtMIC7 showed increased cell proliferation and expressed higher levels of B cell leukemia/lymphoma 2 (BCL-2). These findings contribute to the better understanding of parasite-host interactions at the molecular level during E. tenella infection.

A protein of Eimeria tenella (encoded by the locus ETH_00028350) homologous to Toxoplasma gondii dense granule protein 9, designated as EtHGRA9 hereafter, was reported to be expressed in all life cycle stages of E. tenella. However, no data are currently available regarding its functional properties. In the present study, a recombinant vector harboring a 741 bp gene segment encoding the mature form of EtHGRA9 was constructed and transfected into leghorn male hepatoma (LMH) cells. Then, transcriptomic analysis of the transfected LMH cells was carried out by using a high-throughput RNA-seq technology. The LMH cells overexpressing EtHGRA9 was validated by means of Western blotting as well as indirect immunofluorescence staining. The results demonstrated that the expression of 547 genes (275 upregulated genes and 272 downregulated genes) was altered by EtHGRA9. The quantitative real-time polymerase chain reaction (qRT-PCR) validation of the ten genes with differential expression between the two groups was consistent with the transcriptome analysis. According to pathway enrichment analysis for the obtained differentially expressed genes, seven pathways were significantly affected by EtHGRA9, such as cytokine-cytokine receptor interaction, MAPK signaling pathway, and protein processing in endoplasmic reticulum. Our data reveal several possible roles of EtHGRA9 in immune or inflammatory responses, which paves the way for a better understanding of the molecular interplay between E. tenella and its host.

ABSTRACT: Though genome sequencing of Eimeria tenella predicts more than 8,000 genes, the molecular functions of many proteins remain unknown. In this study, the coding region corresponding to the mature peptide of a hypothetical protein of E. tenella (ETH_00023950) was amplified and expressed in a bacterial system. Following preparation of polyclonal antibody that recognizes ETH_00023950, the expression of ETH_00023950 in merozoites was examined. Meanwhile, we determined the transcriptomic responses of the leghorn male hepatoma (LMH) cells to its expression. Sequencing analysis showed that one single nucleotide polymorphism and one indel of ETH_00023950 of E. tenella SD-01 strain were found compared with that of the UK reference Houghton strain, leading to a frame shift and a premature stop codon. The expression of ETH_00023950 in E. tenella merozoites was confirmed by indirect immunofluorescence and Western blot analysis. Transcriptomic analysis showed that ETH_00023950 altered the expression of 2,680 genes (321 downregulated genes and 2,359 upregulated genes) in LMH cells. The RNA-sequencing data were consistent with the results of the quantitative real-time polymerase chain reaction (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that differentially expressed transcripts were significantly related to 8 pathways, including oxidative phosphorylation and TGF-beta signaling pathway. These findings contribute to understanding host-pathogen interaction and secondary bacterial infections related to E. tenella.

Though a number of Eimeria tenella rhoptry kinase family proteins have been identified, little is known about their molecular functions. In the present study, the gene fragment encoding the matured peptide of E. tenella rhoptry kinase family protein 17 (EtROP17) was used to construct a recombinant vector, followed by transfection into leghorn male hepatoma (LMH) cells. Then, the transcriptional changes in the transfected cells were determined by RNA-seq. The expression of EtROP17 in LMH cells was validated by both Western blot and indirect immunofluorescence analysis. Our analysis showed that EtROP17 altered the expression of 309 genes (114 downregulated genes and 195 upregulated genes) in LMH cells. The quantitative real-time polymerase chain reaction (qRT-PCR) results of the selected differentially expressed genes (DEGs) were consistent with the RNA-seq data. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that DEGs were significantly enriched in nine pathways, such as toll-like receptor signaling pathway, ECM-receptor interaction, intestinal immune network for IgA production and focal adhesion. These findings reveal several potential roles of EtROP17, which contribute to understanding the molecular mechanisms underlying the host-parasite interplay.

Objective: The alternate healthy eating index has been associated with depression. However, results reported in the literature are inconsistent. The present meta-analysis determined the association between the AHEI or AHEI-2010 and depression in adults without chronic disease. Methods: Nine electronic databases and the reference lists of identified studies were systematically searched for studies published up to December 2016. Articles examining the association between depression and the AHEI or AHEI-2010 in adults were included. Results: We identified eight observational studies with 10 effect sizes involving a total of 38,360 participants. When both the AHEI and AHEI-2010 were considered, the dietary index score was associated with a significant reduction in depression risk (odds ratio OR=0.70, 95% confidence interval CI=0.57–0.87). However, the subgroup analysis indicated that the AHEI-2010 (OR=0.69, 95% CI=0.56–0.89), but not the AHEI (OR=0.60, 95% CI=0.30–1.17), was significantly associated with reduced odds of depression. The heterogeneity among the included studies was significantly high (Q=48.9, P<0.01, I2=81.60%). Discussion: Our findings suggest that the AHEI-2010 is associated with a reduction in depression risk. However, well-designed randomized controlled trials must be conducted to confirm the causal relationship between the AHEI-2010 and depression. [ABSTRACT FROM AUTHOR]

Byline: Jing-Quan. Zheng, Kun. Wang, Dee. Pei, Yen-Lin. Chen, Yen-Lin. Chang, Chun-Hsien. Hsu, Tsan-Ming. Huang, Mei-Yu. Lin, Pao-Ying. Lin, Jiunn-Diann. Lin Objectives: Insulin resistance is one of the important underlying [...]