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Arrested crossover precursor structures form stable homologous bonds in a Tetrahymena meiotic mutant.

ABSTRACT: Meiotic DNA double-strand breaks produce reciprocally exchanged DNA strands, which mature into chiasmata that hold homologous chromosomes together as bivalents. These bivalents are subsequently separated in the first meiotic division. In a mutant lacking the newly identified Tetrahymena gene APRO1 (Anaphase promoting 1), meiosis is arrested by the end of prophase. Mature chiasmata are not formed but bivalents are connected via a molecular precursor structure. In-depth analysis of this arrested intermediate structure may help to elucidate the noncanonical molecular recombination pathway in Tetrahymena.

SUBMITTER: Tian M

PROVIDER: S-EPMC8849441 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Arrested crossover precursor structures form stable homologous bonds in a Tetrahymena meiotic mutant.

Tian Miao M Mochizuki Kazufumi K Loidl Josef J

PloS one 20220216 2

Meiotic DNA double-strand breaks produce reciprocally exchanged DNA strands, which mature into chiasmata that hold homologous chromosomes together as bivalents. These bivalents are subsequently separated in the first meiotic division. In a mutant lacking the newly identified Tetrahymena gene APRO1 (Anaphase promoting 1), meiosis is arrested by the end of prophase. Mature chiasmata are not formed but bivalents are connected via a molecular precursor structure. In-depth analysis of this arrested i ...[more]

PMID: 35171923

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