Transgenerationally Precipitated Meiotic Chromosome Instability Fuels Rapid Karyotypic Evolution and Phenotypic Diversity in an Artificially Constructed Allotetraploid Wheat (AADD)

Xiaowan Gou; Yao Bian; Ai Zhang; Huakun Zhang; Bin Wang; Ruili Lv; Juzuo Li; Bo Zhu; Lei Gong; Bao Liu

doi:10.1093/molbev/msy009

Transgenerationally Precipitated Meiotic Chromosome Instability Fuels Rapid Karyotypic Evolution and Phenotypic Diversity in an Artificially Constructed Allotetraploid Wheat (AADD)

Molecular Biology and Evolution ◽

10.1093/molbev/msy009 ◽

2018 ◽

Vol 35 (5) ◽

pp. 1078-1091 ◽

Cited By ~ 8

Author(s):

Xiaowan Gou ◽

Yao Bian ◽

Ai Zhang ◽

Huakun Zhang ◽

Bin Wang ◽

...

Keyword(s):

Phenotypic Diversity ◽

Meiotic Chromosome ◽

Chromosome Instability ◽

Karyotypic Evolution

Download Full-text

Chromosome instability in wheat plants regenerated from suspension culture

Genome ◽

10.1139/g87-104 ◽

1987 ◽

Vol 29 (4) ◽

pp. 627-629 ◽

Cited By ~ 6

Author(s):

George Fedak ◽

K. C. Armstrong ◽

R. J. Handyside

Keyword(s):

Triticum Aestivum ◽

Suspension Culture ◽

Key Words ◽

Chinese Spring ◽

Meiotic Chromosome ◽

Chromosome Instability ◽

Wheat Chromosome ◽

Chromosome Behaviour ◽

Meiotic Configuration ◽

Culture Suspension

Plants of Triticum aestivum cv. Chinese Spring were regenerated from 30 calli obtained from suspension cultures. All four plants showed abnormal meiotic chromosome behaviour relative to the control. The average meiotic configuration over all plants was 1.55 I + 18.16 II + 0.30 III + 0.82 IV. In addition, an isochromosome was frequently observed in cells of all plants, which was indicative of centromeric breaks. Key words: culture (suspension), wheat, chromosome instability.

Download Full-text

Prolonged ovarian storage of mature Drosophila oocytes dramatically increases meiotic spindle instability

eLife ◽

10.7554/elife.49455 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 5

Author(s):

Ethan J Greenblatt ◽

Rebecca Obniski ◽

Claire Mical ◽

Allan C Spradling

Keyword(s):

Meiotic Chromosome ◽

Chromosome Instability ◽

Oocyte Quality ◽

Ribosome Profiling ◽

Meiotic Spindle ◽

Human Embryos ◽

Prolonged Storage ◽

Translational Efficiency ◽

Human Oocytes ◽

In The Wild

Human oocytes frequently generate aneuploid embryos that subsequently miscarry. In contrast, Drosophila oocytes from outbred laboratory stocks develop fully regardless of maternal age. Since mature Drosophila oocytes are not extensively stored in the ovary under laboratory conditions like they are in the wild, we developed a system to investigate how storage affects oocyte quality. The developmental capacity of stored mature Drosophila oocytes decays in a precise manner over 14 days at 25°C. These oocytes are transcriptionally inactive and persist using ongoing translation of stored mRNAs. Ribosome profiling revealed a progressive 2.3-fold decline in average translational efficiency during storage that correlates with oocyte functional decay. Although normal bipolar meiotic spindles predominate during the first week, oocytes stored for longer periods increasingly show tripolar, monopolar and other spindle defects, and give rise to embryos that fail to develop due to aneuploidy. Thus, meiotic chromosome segregation in mature Drosophila oocytes is uniquely sensitive to prolonged storage. Our work suggests the chromosome instability of human embryos could be mitigated by reducing the period of time mature human oocytes are stored in the ovary prior to ovulation.

Download Full-text

Prolonged ovarian storage of mature Drosophila oocytes dramatically increases meiotic spindle instability

10.1101/675389 ◽

2019 ◽

Author(s):

Ethan J. Greenblatt ◽

Rebecca Obniski ◽

Claire Mical ◽

Allan C. Spradling

Keyword(s):

Meiotic Chromosome ◽

Chromosome Instability ◽

Functional Decline ◽

Small Heat Shock Protein ◽

Oocyte Quality ◽

Ribosome Profiling ◽

Meiotic Spindle ◽

Mrna Levels ◽

Dependent Manner ◽

Human Oocytes

SummaryMore than 95% of fertilized Drosophila oocytes from outbred stocks develop fully regardless of maternal age, in contrast to human oocytes, which frequently generate non-viable aneuploid embryos. Since Drosophila oocytes are normally stored only briefly prior to ovulation, unlike their human counterparts, we investigated the effects of storage on oocyte quality. Using a novel system to acquire oocytes held for known periods, we analyzed by ribosome profiling how translation and cellular function change over time. Oocyte developmental capacity decays in a precise temperature-dependent manner over 1-4 weeks, due to a progressive inability to complete meiosis. Meiotic metaphase genes, the Fmr1 translational regulator, and the small heat shock protein chaperones Hsp26 and Hsp27 are preferentially translated during storage, and oocytes lacking Hsp26 and Hsp27 age prematurely. However translation falls generally 2.3-fold with age despite constant mRNA levels, and this inability to maintain translational equilibrium correlates with oocyte functional decline. These findings show that meiotic chromosome segregation in Drosophila oocytes is uniquely sensitive to prolonged quiescence, and suggest that the extended storage of mature human oocytes contributes to their chromosome instability. If so, then these problems may be more amenable to intervention than previously supposed.

Download Full-text