One Cell, Two Gears: Extensive Somatic Genome Plasticity Accompanies High Germline Genome Stability in Paramecium.

ABSTRACT: Mutation accumulation (MA) experiments are conventionally employed to study spontaneous germline mutations. However, MA experiments can also shed light on somatic genome plasticity in a habitual and genetic drift-maximizing environment. Here, we revisit an MA experiment that uncovered extraordinary germline genome stability in Paramecium tetraurelia, a single-celled eukaryote with nuclear dimorphism. Our re-examination of isogenic P. tetraurelia MA lines propagated in nutrient-rich medium for >40 sexual cycles reveals that their polyploid somatic genome accrued hundreds of intervening DNA segments (IESs), which are normally eliminated during germline-soma differentiation. These IESs frequently occupy a fraction of the somatic DNA copies of a given locus, producing IES excision/retention po

SUBMITTER: Catania F 

PROVIDER: S-EPMC8670300 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature