Analysis of the complete mitochondrial genome of Pochonia chlamydosporia suggests a close relationship to the invertebrate-pathogenic fungi in Hypocreales

Abstract

BackgroundThe fungus Pochonia chlamydosporia parasitizes nematode eggs and has become one of the most promising biological control agents (BCAs) for plant-parasitic nematodes, which are major agricultural pests that cause tremendous economic losses worldwide. The complete mitochondrial (mt) genome is expected to open new avenues for understanding the phylogenetic relationships and evolution of the invertebrate-pathogenic fungi in Hypocreales.ResultsThe complete mitogenome sequence of P. chlamydosporia is 25,615 bp in size, containing the 14 typical protein-coding genes, two ribosomal RNA genes, an intronic ORF coding for a putative ribosomal protein (rps3) and a set of 23 transfer RNA genes (trn) which recognize codons for all amino acids. Sequence similarity studies and syntenic gene analyses show that 87.02% and 58.72% of P. chlamydosporia mitogenome sequences match 90.50% of Metarhizium anisopliae sequences and 61.33% of Lecanicillium muscarium sequences with 92.38% and 86.04% identities, respectively. A phylogenetic tree inferred from 14 mt proteins in Pezizomycotina fungi supports that P. chlamydosporia is most closely related to the entomopathogenic fungus M. anisopliae. The invertebrate-pathogenic fungi in Hypocreales cluster together and clearly separate from a cluster comprising plant-pathogenic fungi (Fusarium spp.) and Hypocrea jecorina. A comparison of mitogenome sizes shows that the length of the intergenic regions or the intronic regions is the major size contributor in most of mitogenomes in Sordariomycetes. Evolutionary analysis shows that rps3 is under positive selection, leading to the display of unique evolutionary characteristics in Hypocreales. Moreover, the variability of trn distribution has a clear impact on gene order in mitogenomes. Gene rearrangement analysis shows that operation of transposition drives the rearrangement events in Pezizomycotina, and most events involve in trn position changes, but no rearrangement was found in Clavicipitaceae.ConclusionsWe present the complete annotated mitogenome sequence of P. chlamydosporia. Based on evolutionary and phylogenetic analyses, we have determined the relationships between the invertebrate-pathogenic fungi in Hypocreales. The invertebrate-pathogenic fungi in Hypocreales referred to in this paper form a monophyletic group sharing a most recent common ancestor. Our rps3 and trn gene order results also establish a foundation for further exploration of the evolutionary trajectory of the fungi in Hypocreales.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-015-0341-8) contains supplementary material, which is available to authorized users.

Volatile organic compounds from entomopathogenic and nematophagous fungi, repel banana black weevil (Cosmopolites sordidus)

“…chlamydosporia 123, a nematophagous fungus closely related to M. anisopliae [20,21], with a large array of secondary metabolites [80] was also tested for VOCs production. Genomic studies support that some…”

“…Pochonia chlamydosporia [(Goddard) Zare and Gams, 2001] is a nematophagous fungus very close phyllogenomically to M. anisopliae [20,21]. P. chlamydosporia parasitizes nematode eggs and females [22][23][24], it is also an endophyte [25,26] and a soil fungus [27,28].…”

Intra-specific comparison of mitochondrial genomes reveals host gene fragment exchange via intron mobility in Tremella fuciformis

“…Conserved protein-coding genes and rRNAs in fungal mitochondrial genome were annotated by the MFannot [11,49] or BLAST [50] programs; their intron-exon boundaries were identi ed by Clustal W by comparison with intron-free homologous genes of closely related species [50]; and tRNAs were identi ed by MFannot [49], tRNAscan-SE [51], RNAweasel, and/or Rfam [32]. However, because of the great differences existing among intergenic regions of interspeci c mitochondrial genomes, some annotation errors might have occurred in these alignments.…”

Complete mitogenome of the high ethanol production fungusFusarium oxysporumMh2-2

“…We find that the complete mitogenome of FoxM is 46 kb (GenBank accession no. MF155191) and it encodes 18 protein-coding genes, including 15 typical genes (three cytochrome c oxidase subunits, cox1-3; one apocytochrome b, cob; three ATP synthase subunits, atp6 and atp8-9; seven subunits of NADH dehydrogenase, nad1-6 and nad4L; one ribosomal protein, rps3) that are commonly found in fungal mitogenomes in Hypocreales (Lin et al 2015), and three non-typical genes include one LAGLIDADG endonuclease (mh2-na2) and two hypothetical proteins. Additionally, the FoxM mitochondrial genome encodes 26 tRNAs and two rRNAs (rns and rnl).…”