Unknown

Dataset Information

0

Sex- and Gamete-Specific Patterns of X Chromosome Segregation in a Trioecious Nematode.


ABSTRACT: Three key steps in meiosis allow diploid organisms to produce haploid gametes: (1) homologous chromosomes (homologs) pair and undergo crossovers; (2) homologs segregate to opposite poles; and (3) sister chromatids segregate to opposite poles. The XX/XO sex determination system found in many nematodes [1] facilitates the study of meiosis because variation is easily recognized [2-4]. Here we show that meiotic segregation of X chromosomes in the trioecious nematode Auanema rhodensis [5] varies according to sex (hermaphrodite, female, or male) and type of gametogenesis (oogenesis or spermatogenesis). In this species, XO males exclusively produce X-bearing sperm [6, 7]. The unpaired X precociously separates into sister chromatids, which co-segregate with the autosome set to generate a functional haplo-X sperm. The other set of autosomes is discarded into a residual body. Here we explore the X chromosome behavior in female and hermaphrodite meioses. Whereas X chromosomes segregate following the canonical pattern during XX female oogenesis to yield haplo-X oocytes, during XX hermaphrodite oogenesis they segregate to the first polar body to yield nullo-X oocytes. Thus, crosses between XX hermaphrodites and males yield exclusively male progeny. During hermaphrodite spermatogenesis, the sister chromatids of the X chromosomes separate during meiosis I, and homologous X chromatids segregate to the functional sperm to create diplo-X sperm. Given these intra-species, intra-individual, and intra-gametogenesis variations in the meiotic program, A. rhodensis is an ideal model for studying the plasticity of meiosis and how it can be modulated.

SUBMITTER: Tandonnet S 

PROVIDER: S-EPMC5772170 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

altmetric image

Publications

Sex- and Gamete-Specific Patterns of X Chromosome Segregation in a Trioecious Nematode.

Tandonnet Sophie S   Farrell Maureen C MC   Koutsovoulos Georgios D GD   Blaxter Mark L ML   Parihar Manish M   Sadler Penny L PL   Shakes Diane C DC   Pires-daSilva Andre A  

Current biology : CB 20171221 1


Three key steps in meiosis allow diploid organisms to produce haploid gametes: (1) homologous chromosomes (homologs) pair and undergo crossovers; (2) homologs segregate to opposite poles; and (3) sister chromatids segregate to opposite poles. The XX/XO sex determination system found in many nematodes [1] facilitates the study of meiosis because variation is easily recognized [2-4]. Here we show that meiotic segregation of X chromosomes in the trioecious nematode Auanema rhodensis [5] varies acco  ...[more]

Similar Datasets

| S-EPMC10630426 | biostudies-literature
| S-EPMC2175229 | biostudies-literature
| S-EPMC3711665 | biostudies-literature
| S-EPMC6041754 | biostudies-literature
| S-EPMC4333373 | biostudies-literature
| S-EPMC3529029 | biostudies-literature
| S-EPMC4596671 | biostudies-literature
| S-EPMC4107656 | biostudies-literature
| S-EPMC8903493 | biostudies-literature
| S-EPMC3839911 | biostudies-literature