HEИндивидуална стипендия2023–2025

CHOPPE · Comparative HaplotypOmics of Parthenogenetic Plectus nEmatodes

„Хоризонт Европа“ — Действия „Мария Склодовска-Кюри“

Период: 2023-05-01 → 2025-04-30
Финансиране от ЕС: 173 847 €
Участници: 1
Схема: HORIZON-TMA-MSCA-PF-EF

Линиите свързват координатора с партньорите.

Накратко на български

Геномът на нематодите от род Plectus се анализира, за да се разбере как тези червеи се възпроизвеждат без партньор и оцеляват при замръзване. Това помага да се разбере как липсата на сексуално размножаване и екстремните условия влияят върху еволюцията и структурата на ДНК.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

Comparative HaplotypOmics of Parthenogenetic Plectus nEmatodes

Plectus is a genus of nematodes known for its exclusive parthenogenesis (asexual reproduction). The general predominance of sexual reproduction in metazoans, despite its significant energetic costs compared to asexual modes, represents a long-standing question in evolutionary biology. While parthenogenesis offers advantages such as rapid replication and independence from mate finding, it is predicted to lead to the accumulation of deleterious mutations and slower adaptation due to the lack of meiotic recombination. However, the frequent occurrence of parthenogenetic taxa in extreme environments suggests adaptive benefits. To further adapt to arduous habitats, Plectus has a remarkable ability to enter cryptobiosis (a state of suspended metabolism also observed in tardigrades and rotifers) to survive desiccation or freezing. This phenomenon is expected to damage the genome sequence and to be only sustainable along accrued DNA repair machineries. The lack of high-quality genomic resources for Plectus, with only few fragmented genome assemblies previously published, has severely hindered in-depth analysis of how parthenogenesis and cryptobiosis impact their genome structure and evolution in the context of parthenogenesis and cryptobiosis. CHOPPE first aimed to develop robust methodologies for sequencing and assembling non-model nematode genomes, like Plectus, into collapsed or phased, chromosome-level or highly contiguous sequences. This included utilizing advanced long-read sequencing technologies (PacBio HiFi, Nanopore) and Hi-C reads. Following the application of these methods to several Plectus species, and the closely related sexual species Anaplectus granulosus, the project sought to understand the adaptation and evolution of Plectus, using comparative genomic approaches addressing gene content, repetitive content, and chromosome structure. We additionally aimed to investigate the origin of asexuality in Plectus and test reversal to asexuality. The project also addressed chromosomal adaptations in cryptobiotic nematodes by analyzing chromosome structure conservation in Plectus and Panagrolaimus nematodes, a phylogenetically distant but phenotypically similar cryptobiotic genus.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

Sexual reproduction is a costly but seemingly necessary trait in animals. However, species in diverse branches of the animal kingdom have secondarily reverted to asexual reproduction. In the roundworms (phylum Nematoda), this reversal appears particularly frequent, as parthenogenetic species have emerged in numerous genera. Species in the genus Plectus are obligately parthenogenetic, and are distributed in non-extreme and extreme environments across the globe. Mechanisms leading to the loss of sex, for example hybridisation, have received some attention, but are still poorly understood, in particular on the genomic level. This is in part due to the lack of sequencing and analysis tools for complex genomes of minute organisms.CHOPPE will generate chromosome-level collapsed and phased genome assemblies using latest assembly strategies for several species of Plectus and its closest sexual relative Anaplectus from diverse habitats. CHOPPE will develop new computational methods for generating fully phased assemblies of diverse non-model species. Collapsed assemblies, and haplotype assemblies of several Plectus and Anaplectus species generated in the project, will allow to decipher the genomic basis of their adaption in the context of parthenogenesis and extreme environments. The project will further investigate the reversal to sexuality of Plectus through crossing with heat induced males, and establish this genus as a new model for the study of parthenogenesis.

Оригинален текст от CORDIS (на английски).

Участници

UNIVERSITAT ZU KOLN · KolnКоординаторГермания