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Deep Sequencing Analysis of the Ixodes ricinus Haemocytome.

Kotsyfakis M, Kopáček P, Franta Z, Pedra JH, Ribeiro JM - PLoS Negl Trop Dis (2015)

Bottom Line: A total of 327 transcripts were found significantly over expressed in the hemocyte libraries, including those coding for scavenger receptors, antimicrobial peptides, pathogen recognition proteins, proteases and protease inhibitors.We additionally annotated ubiquitously distributed transcripts associated with immune function, including immune-associated signal transduction proteins and transcription factors, including the STAT transcription factor.A total of 2,860 coding sequences were deposited to GenBank, increasing to 27,547 the number so far deposited by our previous transcriptome studies that serves as a discovery platform for studies with I. ricinus biochemistry and physiology.

View Article: PubMed Central - PubMed

Affiliation: Institute of Parasitology, Biology Center of the Czech Academy of Sciences, Budweis, Czech Republic.

ABSTRACT

Background: Ixodes ricinus is the main tick vector of the microbes that cause Lyme disease and tick-borne encephalitis in Europe. Pathogens transmitted by ticks have to overcome innate immunity barriers present in tick tissues, including midgut, salivary glands epithelia and the hemocoel. Molecularly, invertebrate immunity is initiated when pathogen recognition molecules trigger serum or cellular signalling cascades leading to the production of antimicrobials, pathogen opsonization and phagocytosis. We presently aimed at identifying hemocyte transcripts from semi-engorged female I. ricinus ticks by mass sequencing a hemocyte cDNA library and annotating immune-related transcripts based on their hemocyte abundance as well as their ubiquitous distribution.

Methodology/principal findings: De novo assembly of 926,596 pyrosequence reads plus 49,328,982 Illumina reads (148 nt length) from a hemocyte library, together with over 189 million Illumina reads from salivary gland and midgut libraries, generated 15,716 extracted coding sequences (CDS); these are displayed in an annotated hyperlinked spreadsheet format. Read mapping allowed the identification and annotation of tissue-enriched transcripts. A total of 327 transcripts were found significantly over expressed in the hemocyte libraries, including those coding for scavenger receptors, antimicrobial peptides, pathogen recognition proteins, proteases and protease inhibitors. Vitellogenin and lipid metabolism transcription enrichment suggests fat body components. We additionally annotated ubiquitously distributed transcripts associated with immune function, including immune-associated signal transduction proteins and transcription factors, including the STAT transcription factor.

Conclusions/significance: This is the first systems biology approach to describe the genes expressed in the haemocytes of this neglected disease vector. A total of 2,860 coding sequences were deposited to GenBank, increasing to 27,547 the number so far deposited by our previous transcriptome studies that serves as a discovery platform for studies with I. ricinus biochemistry and physiology.

No MeSH data available.


Related in: MedlinePlus

The tick microplusin family of antimicrobial peptides.A) ClustalW alignment. The symbols at the top of the figure represent (*) identity, (:) similarity, and (.) lesser similarity. B) The neighbour-joining phylogenetic tree from the alignment in (A) following 1,000 bootstraps. Sequence names are represented by the first three letters of the genus name, followed by the first three letters of the species name, followed by their GenBank gene identifier (gi) accession number. Sequences from this work start with IrHem and include IrHemSgMg-674, which is 140-times overexpressed in haemocytes. Ixodes ricinus sequences are indicated by a red circle. The bar at the bottom represents 50% amino acid diversity. The numbers at the nodes represent the per cent bootstrap support. Values below 50 are not shown.
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pntd.0003754.g001: The tick microplusin family of antimicrobial peptides.A) ClustalW alignment. The symbols at the top of the figure represent (*) identity, (:) similarity, and (.) lesser similarity. B) The neighbour-joining phylogenetic tree from the alignment in (A) following 1,000 bootstraps. Sequence names are represented by the first three letters of the genus name, followed by the first three letters of the species name, followed by their GenBank gene identifier (gi) accession number. Sequences from this work start with IrHem and include IrHemSgMg-674, which is 140-times overexpressed in haemocytes. Ixodes ricinus sequences are indicated by a red circle. The bar at the bottom represents 50% amino acid diversity. The numbers at the nodes represent the per cent bootstrap support. Values below 50 are not shown.

Mentions: Microplusin [32] is a cysteine-rich antimicrobial peptide described in the cattle tick Rhipicephalus microplus. One member of this family was enriched 140-times in I. ricinus haemocytes. Alignment of related tick sequences from GenBank (Fig 1A) with our data revealed three prostriate clades and one metastriate clade, all with multiple members (Fig 1B), indicative of a large number of genes and/or alleles in the I. ricinus genome. Interestingly, the I. scapularis and I. ricinus microplusins apparently lack the N-terminal histidine-rich domain important for the bacteriostatic effect of microplusin from R. (B.) microplus by chelating copper ions [33]. Therefore, the antibacterial effect of microplusins from Ixodes sp. needs experimental validation.


Deep Sequencing Analysis of the Ixodes ricinus Haemocytome.

Kotsyfakis M, Kopáček P, Franta Z, Pedra JH, Ribeiro JM - PLoS Negl Trop Dis (2015)

The tick microplusin family of antimicrobial peptides.A) ClustalW alignment. The symbols at the top of the figure represent (*) identity, (:) similarity, and (.) lesser similarity. B) The neighbour-joining phylogenetic tree from the alignment in (A) following 1,000 bootstraps. Sequence names are represented by the first three letters of the genus name, followed by the first three letters of the species name, followed by their GenBank gene identifier (gi) accession number. Sequences from this work start with IrHem and include IrHemSgMg-674, which is 140-times overexpressed in haemocytes. Ixodes ricinus sequences are indicated by a red circle. The bar at the bottom represents 50% amino acid diversity. The numbers at the nodes represent the per cent bootstrap support. Values below 50 are not shown.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4430169&req=5

pntd.0003754.g001: The tick microplusin family of antimicrobial peptides.A) ClustalW alignment. The symbols at the top of the figure represent (*) identity, (:) similarity, and (.) lesser similarity. B) The neighbour-joining phylogenetic tree from the alignment in (A) following 1,000 bootstraps. Sequence names are represented by the first three letters of the genus name, followed by the first three letters of the species name, followed by their GenBank gene identifier (gi) accession number. Sequences from this work start with IrHem and include IrHemSgMg-674, which is 140-times overexpressed in haemocytes. Ixodes ricinus sequences are indicated by a red circle. The bar at the bottom represents 50% amino acid diversity. The numbers at the nodes represent the per cent bootstrap support. Values below 50 are not shown.
Mentions: Microplusin [32] is a cysteine-rich antimicrobial peptide described in the cattle tick Rhipicephalus microplus. One member of this family was enriched 140-times in I. ricinus haemocytes. Alignment of related tick sequences from GenBank (Fig 1A) with our data revealed three prostriate clades and one metastriate clade, all with multiple members (Fig 1B), indicative of a large number of genes and/or alleles in the I. ricinus genome. Interestingly, the I. scapularis and I. ricinus microplusins apparently lack the N-terminal histidine-rich domain important for the bacteriostatic effect of microplusin from R. (B.) microplus by chelating copper ions [33]. Therefore, the antibacterial effect of microplusins from Ixodes sp. needs experimental validation.

Bottom Line: A total of 327 transcripts were found significantly over expressed in the hemocyte libraries, including those coding for scavenger receptors, antimicrobial peptides, pathogen recognition proteins, proteases and protease inhibitors.We additionally annotated ubiquitously distributed transcripts associated with immune function, including immune-associated signal transduction proteins and transcription factors, including the STAT transcription factor.A total of 2,860 coding sequences were deposited to GenBank, increasing to 27,547 the number so far deposited by our previous transcriptome studies that serves as a discovery platform for studies with I. ricinus biochemistry and physiology.

View Article: PubMed Central - PubMed

Affiliation: Institute of Parasitology, Biology Center of the Czech Academy of Sciences, Budweis, Czech Republic.

ABSTRACT

Background: Ixodes ricinus is the main tick vector of the microbes that cause Lyme disease and tick-borne encephalitis in Europe. Pathogens transmitted by ticks have to overcome innate immunity barriers present in tick tissues, including midgut, salivary glands epithelia and the hemocoel. Molecularly, invertebrate immunity is initiated when pathogen recognition molecules trigger serum or cellular signalling cascades leading to the production of antimicrobials, pathogen opsonization and phagocytosis. We presently aimed at identifying hemocyte transcripts from semi-engorged female I. ricinus ticks by mass sequencing a hemocyte cDNA library and annotating immune-related transcripts based on their hemocyte abundance as well as their ubiquitous distribution.

Methodology/principal findings: De novo assembly of 926,596 pyrosequence reads plus 49,328,982 Illumina reads (148 nt length) from a hemocyte library, together with over 189 million Illumina reads from salivary gland and midgut libraries, generated 15,716 extracted coding sequences (CDS); these are displayed in an annotated hyperlinked spreadsheet format. Read mapping allowed the identification and annotation of tissue-enriched transcripts. A total of 327 transcripts were found significantly over expressed in the hemocyte libraries, including those coding for scavenger receptors, antimicrobial peptides, pathogen recognition proteins, proteases and protease inhibitors. Vitellogenin and lipid metabolism transcription enrichment suggests fat body components. We additionally annotated ubiquitously distributed transcripts associated with immune function, including immune-associated signal transduction proteins and transcription factors, including the STAT transcription factor.

Conclusions/significance: This is the first systems biology approach to describe the genes expressed in the haemocytes of this neglected disease vector. A total of 2,860 coding sequences were deposited to GenBank, increasing to 27,547 the number so far deposited by our previous transcriptome studies that serves as a discovery platform for studies with I. ricinus biochemistry and physiology.

No MeSH data available.


Related in: MedlinePlus