Near chromosome–level genome assembly of the microsporidium <i>Hamiltosporidium tvaerminnensis</i>

Angst, Pascal; Pombert, Jean‐François; Ebert, Dieter; Fields, Peter D.

doi:10.1093/g3journal/jkad185

Cited by 6 publications

(1 citation statement)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In 2001, the first microsporidian genome was published, belonging to Encephalitozoon cuniculi, a parasite of the European rabbit (Oryctolagus cuniculus) used as a model in infection studies [9]. More recently, many studies have targeted microsporidian genomes, and microsporidia have become a valuable model for studying the evolution of parasitism [10][11][12][13][14][15]. Microsporidia have the smallest eukaryotic genomes, having undergone extreme reduction, losing many metabolic pathways, such as glycolysis and lipid biosynthesis [11,[16][17][18][19][20][21] and lacking mitochondrial genomes because of reductive evolution of mitochondria to form mitosomes [22].…”

Section: Introductionmentioning

confidence: 99%

Polyploidy is widespread in Microsporidia

Khalaf,

Jaron,

Blaxter

et al. 2023

Preprint

View full text Add to dashboard Cite

Microsporidia are obligate intracellular eukaryotic parasites with an extremely broad host range. They have both economic and public health importance. Ploidy in microsporidia is variable, with a few species formally identified as diploid and one as polyploid. Given the increase in the number of studies sequencing microsporidian genomes, it is now possible to assess ploidy levels across all currently-explored microsporidian diversity. We estimate ploidy for all microsporidian datasets available on the Sequence Read Archive (SRA) using k-mer-based analyses, and demonstrate that polyploidy is widespread in Microsporidia, and that ploidy change is dynamic in the group. Using genome-wide heterozygosity estimates, we also show that polyploid microsporidian genomes are relatively homozygous, and we discuss the implications of these findings on the timing of polyploidisation events and their origin.Author SummaryMicrosporidia are single-celled intracellular parasites, distantly related to fungi, that can infect a broad range of hosts, from humans all the way to protozoans. Exploiting the wealth of microsporidian genomic data available, we use k-mer based analyses to assess ploidy status across the group. Understanding a genome’s ploidy is crucial in order to assemble it effectively, and may also be relevant for better understanding a parasite’s behaviour and life cycle. We show that tetraploidy is present in at least six species in Microsporidia, and that these polyploidisation events are likely to have occurred independently. We discuss why these findings may be paradoxical, given that Microsporidia, like other intracellular parasites, have extremely small, reduced genomes.

show abstract

Section: Introductionmentioning

confidence: 99%

Polyploidy is widespread in Microsporidia

Khalaf,

Jaron,

Blaxter

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

Mikrosporidien-Genome als Fenster zu deren Evolution

Angst,

Ebert

2024

Biospektrum

View full text Add to dashboard Cite

Genomics is a powerful toolkit for unravelling how evolutionary processes drive organisms’ small- and large-scale genetic variation. Several outstanding questions remain concerning the evolution of genome size and architecture, especially in intracellular parasites. Microsporidia became a model for this field of study as they exhibit genome size variation of more than an order of magnitude. Here, we discuss evolution in the large-genome microsporidium Hamiltosporidium tvaerminnensis, a parasite of a water flea.

show abstract

De Novo Long-Read Genome Assembly and Annotation of the Mosquito Gut-Dwelling Fungus, Smittium minutisporum

Prakash,

Wang

2024

Genome Biology and Evolution

View full text Add to dashboard Cite

Mosquito guts host a variety of microbes, yet fungi are often overlooked. Smittium (Harpellales, Zoopagomycota) comprises numerous species that are obligate symbionts residing in the hindgut of mosquito larvae. Despite their association with pathogen-bearing vectors, these fungal symbionts remain understudied, largely due to the lack of high-quality genome resources. This limitation has impeded a deeper understanding of their genome biology and adaptive strategies in relation to their mosquito hosts, which may hold significant epidemiological implications. To address this gap, we generated the first reference-quality genome assembly for this group of fungi, using PacBio HiFi long-reads for an axenic culture of Smittium minutisporum, originally isolated from the eastern treehole mosquito, Aedes Triseriatus. The genome assembly consists of 53 contigs, spanning a total length of 32.5 Mb, and is predicted to encode 8,254 protein-coding genes, with repetitive regions constituting 25.22% of the genome. Notably, despite being highly contiguous and gap-free, the BUSCO analysis suggests a completeness score of 71.8%, implying unusual genome features, possibly shaped by adaptation and specialization within the mosquito gut. This high-quality genome resource will be invaluable for advancing our understanding of mosquito gut-dwelling fungi, their natural history, and their cryptic symbiosis with insect hosts.

show abstract

Near chromosome–level genome assembly of the microsporidium Hamiltosporidium tvaerminnensis

Cited by 6 publications

References 70 publications

Polyploidy is widespread in Microsporidia

Polyploidy is widespread in Microsporidia

Mikrosporidien-Genome als Fenster zu deren Evolution

De Novo Long-Read Genome Assembly and Annotation of the Mosquito Gut-Dwelling Fungus, Smittium minutisporum

Contact Info

Product

Resources

About