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bioRxiv · 10.1101/2024.11.13.623465

Genome content in the non-model ciliate Chilodonella uncinata: insights into nuclear architecture, gene-sized chromosomes among the total DNA in their somatic macronuclei during their development

Ahsan, R.·Maurer-Alcala{acute}, X. X.·Katz, L. A.
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Abstract

Ciliates are a model lineage for studies of genome architecture given their unusual genome structures. All ciliates have both somatic macronuclei (MAC) and germline micronuclei (MIC), both of which develop from a zygotic nucleus following sex (i.e., conjugation). Nuclear developmental stages are not as well explored among non-model ciliate genera, including Chilodonella uncinata (Class-Phyllopharyngea), the focus of our work. Here, we characterize nuclear architecture and genome dynamics in C. uncinata by combining DAPI (4',6-diamidino-2-phenylindole) staining and fluorescence in situ hybridization (FISH) techniques with confocal microscopy. We developed a telomere probe for staining alongside DAPI, which allows for the identification of fragmented somatic chromosomes among the total DNA in the nuclei. We quantify both total DNA and telomere-bound signals to explore changes in DNA content and chromosome maturation across Chilodonellas nuclear life cycle. Specifically, we find that MAC developmental stages in the ciliate C. uncinata are different than the data reported from other ciliate species. These data provide insights into nuclear dynamics during nuclear development and enrich our understanding of genome evolution in non-model ciliates.

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Ahsan, R., Maurer-Alcala{acute}, X. X., Katz, L. A.. 2024-11-15. Genome content in the non-model ciliate Chilodonella uncinata: insights into nuclear architecture, gene-sized chromosomes among the total DNA in their somatic macronuclei during their development. https://doi.org/10.1101/2024.11.13.623465

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