Comparative transcriptome analysis of second- and third-generation merozoites of Eimeria necatrix

Abstract

Background Eimeria is a common genus of apicomplexan parasites that infect diverse vertebrates, most notably poultry, causing serious disease and economic losses. Eimeria species have complex life-cycles consisting of three developmental stages. However, the molecular basis of the Eimeria reproductive mode switch remains an enigma.MethodsTotal RNA extracted from second- (MZ-2) and third-generation merozoites (MZ-3) of Eimeria necatrix was subjected to transcriptome analysis using RNA sequencing (RNA-seq) followed by qRT-PCR validation.ResultsA total of 6977 and 6901 unigenes were obtained from MZ-2 and MZ-3, respectively. Approximately 2053 genes were differentially expressed genes (DEGs) between MZ-2 and MZ-3. Compared with MZ-2, 837 genes were upregulated and 1216 genes were downregulated in MZ-3. Approximately 95 genes in MZ-2 and 48 genes in MZ-3 were further identified to have stage-specific expression. Gene ontology category and KEGG analysis suggested that 216 upregulated genes in MZ-2 were annotated by 70 GO assignments, 242 upregulated genes were associated with 188 signal pathways, while 321 upregulated genes in MZ-3 were annotated by 56 GO assignments, 322 upregulated genes were associated with 168 signal pathways. The molecular functions of upregulated genes in MZ-2 were mainly enriched for protein degradation and amino acid metabolism. The molecular functions of upregulated genes in MZ-3 were mainly enriched for transcriptional activity, cell proliferation and cell differentiation.ConclusionsTo the best of our knowledge, this is the first RNA-seq data study of the MZ-2 and MZ-3 stages of E. necatrix; it demonstrates a high number of differentially expressed genes between the MZ-2 and MZ-3 of E. necatrix. This study forms a basis for deciphering the molecular mechanisms underlying the shift from the second to third generation schizogony in Eimeria. It also provides valuable resources for future studies on Eimeria, and provides insight into the understanding of reproductive mode plasticity in different Eimeria species.Electronic supplementary materialThe online version of this article (doi:10.1186/s13071-017-2325-z) contains supplementary material, which is available to authorized users.

Comparative Time-Scale Gene Expression Analysis Highlights the Infection Processes of Two Amoebophrya Strains

“…Amongst the upregulated genes at the early stages of the infection, we observed overrepresentation of the BRITE categories related to Transcription and Translation, implying that Amoebophrya infection resulted in the activation of protein synthesis. Similar pattern of overexpression of proteins involved in the translation process has also been observed in gene expression studies of other apicomplexan parasite models, such as Toxoplasma tachyzoites (Cleary et al, 2002 ), Cryptosporidium sporozoites (Lippuner et al, 2018 ), and Eimeria merozoites (Su et al, 2017 ). The abundance of messenger RNAs for ribosomal proteins, from the early pre-ribosomes, nuclear and cytoplasmic maturation up to the surveillance system (Thomson et al, 2013 ), recalls extensive protein translation needed after the invasion of the host cell.…”

Comparative transcriptome analysis of Eimeria maxima (Apicomplexa: Eimeriidae) suggests DNA replication activities correlating with its fecundity

“…In addition, the time required for invasion for both the precocious line and the wild strain should be measured more precisely, so that we can confirm our hypothesis. As we have presented, genes were significantly more enriched in protein translation related progresses in the merozoite stage (this also happened in the 3rd merozoite stage of E. necartrix [ 37 ]) than in the sporulated oocyst stage. This result suggests that merozoites have very fast metabolisms as a result of the fast growth, division and interaction with the host environment.…”

Characterization of Cystoisospora suis sexual stages in vitro

“…Identification of genes linked to the sexual stages is crucial to understand the developmental biology and the fertilization process of organisms with sexual development, including apicomplexan protozoans. Here, we analyzed eight of the genes with highest upregulated transcripts in microgametes, macrogametes and oocysts based on previous studies in Apicomplexa [11,12,27,29,31,[39][40][41][42]. To identify genes or their orthologues related to the sexual development in C. suis, we used the ToxoDB parasite database and determined four genes related to sexual stages and four genes related to meiosis and cellular division (see Table 1).…”