Three-dimensional memory of nuclear organization through cell cycles DOI Creative Commons
Shin Fujishiro, Masaki Sasai

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 25, 2024

The genome in the cell nucleus is organized by a dynamic process influenced structural memory from mitosis. In this study, we develop model of human dynamics through cycles extending previously developed whole-genome to cover mitotic phase. With extension, focus on role and cycle organization. simulation progresses mitosis interphase subsequent mitosis, leading successive cycles. During our describes microtubule dynamics, showing how forces orchestrate assembly chromosomes into rosette ring structure at metaphase. explains positioning depends their size metaphase configuration persists dimensions perpendicular division axis, effectively guiding distribution chromosome territories over multiple At onset each G1 phase, phase separation active inactive chromatin domains occurs, A/B compartmentalization. Our cycling simulations show that compartments are unaffected previous consistently established cycle. study highlights interplay between across cycles, providing new perspective for analyses cellular processes.

Language: Английский

Three-dimensional memory of nuclear organization through cell cycles DOI
Shin Fujishiro, Masaki Sasai

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(6)

Published: Feb. 13, 2025

The genome in the cell nucleus is organized by a dynamic process influenced structural memory from mitosis. In this study, we develop model of human dynamics through cycles extending previously developed whole-genome to cover mitotic phase. With extension, focus on role and cycle organization. simulation progresses mitosis interphase subsequent mitosis, leading successive cycles. During our describes microtubule dynamics, showing how forces orchestrate assembly chromosomes into rosette ring structure at metaphase. explains positioning depends their size metaphase configuration persists dimensions perpendicular division axis, effectively guiding distribution chromosome territories over multiple At onset each G1 phase, phase separation active inactive chromatin domains occurs, A/B compartmentalization. Our cycling simulations show that compartments are unaffected previous consistently established cycle. study highlights interplay between across cycles, providing insights for analyses cellular processes.

Language: Английский

Citations

1
Chromosome segregation errors during early embryonic development DOI Creative Commons
Hirohisa Kyogoku

Reproductive Medicine and Biology, Journal Year: 2025, Volume and Issue: 24(1)

Published: Jan. 1, 2025

Abstract Background Mitosis maintains a genome's genetic information in daughter cells by accurately segregating chromosomes. However, chromosome aberrations are common during early mammalian embryogenesis. Chromosomal abnormalities the stages of embryogenesis result formation mosaic embryos, wherein with normal genomes coexist exhibiting abnormal genomes. The precise frequency and etiology such remain unclear. It is postulated that these contribute to number conditions, including infertility congenital diseases as Down's syndrome. Methods This review synthesizes current literature data elucidate causes implications embryos. places particular emphasis on identifying patterns mosaicism investigating underlying mechanisms responsible for abnormalities. Main Findings embryos were examined context DNA replication embryonic development. Conclusion A deeper understanding could help develop new treatments advance research cancers caused article reviews knowledge gaps segregation future directions this field.

Language: Английский

Citations

0
Meiosis-specific distal cohesion site decoupled from the kinetochore DOI Creative Commons
Bo Pan, Melania Bruno, Todd S. Macfarlan

et al.

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: March 3, 2025

Abstract Primary constriction of the M-phase chromosome serves as a marker for kinetochore position. Underlying this observation is concept that spatially linked with pericentromere where sister-chromatids are cohered. Here, we find an unconventional chromatid-cohesion pattern in Peromyscus oocytes, sister chromatids cohered at end, separated from kinetochore. This distal locus enriches cohesin protectors specifically during meiosis, and chromosomes additional cohesion site exhibit enhanced protection anaphase I compared to those without it, implying adaptive evolution ensure meiosis. The corresponds centromeric satellite block, located far block building Analyses on three species reveal internal consistently assembles mitosis whereas selectively meiosis promote cohesion. Our study demonstrates regulation flexible, controlling segregation cell-type dependent manner.

Language: Английский

Citations

0
Near millimolar concentration of nucleosomes in mitotic chromosomes from late prometaphase into anaphase DOI Creative Commons
Fernanda Cisneros-Soberanis, Eva L. Simpson, Alison J. Beckett

et al.

The Journal of Cell Biology, Journal Year: 2024, Volume and Issue: 223(11)

Published: Aug. 26, 2024

Chromosome compaction is a key feature of mitosis and critical for accurate chromosome segregation. However, precise quantitative analysis geometry during mitotic progression lacking. Here, we use volume electron microscopy to map, with nanometer precision, chromosomes from prometaphase through telophase in human RPE1 cells. During prometaphase, acquire smoother surface, their arms shorten, the primary centromeric constriction formed. The chromatin progressively compacted, ultimately reaching remarkable nucleosome concentration over 750 µM late that remains relatively constant metaphase early anaphase. Surprisingly, then increase anaphase prior deposition nuclear envelope. plateau total described here consistent proposals final stages condensation involve limit density, such as might be expected process involving phase separation.

Language: Английский

Citations

3
Chromosome number alterations cause apoptosis and cellular hypertrophy in induced pluripotent stem cell models of embryonic epiblast cells DOI Creative Commons

Althea Stella Anil Martis,

Loshini Soundararajan, Prakash Shetty

et al.

Biology Open, Journal Year: 2025, Volume and Issue: 14(1)

Published: Jan. 15, 2025

ABSTRACT Chromosomal aneuploidies are a major cause of developmental failure and pregnancy loss. To investigate the possible consequences aneuploidy on early embryonic development in vitro, we focused primed pluripotent stem cells that relatable to epiblast post-implantation embryos vivo. We used human induced (iPSCs) as an model altered chromosome numbers by treating with reversine, small-molecule inhibitor monopolar spindle 1 kinase (MSP1) inactivates assembly checkpoint, which has been strongly implicated mis-segregation generation. Upon reversine treatment, obtained varied chromosomal content retained pluripotency potential differentiate into three germ lineages. However, these displayed lagging chromosomes, increased micronuclei content, high p53 expression excessive apoptotic activity. Cell proliferation was not affected. Prolonged vitro culture resulted selective pool supernumerary exhibited cellular hypertrophy, enlarged nuclei, overproduction total RNAs proteins. conclude DNA damage responses, apoptosis, improper mass functions mechanisms contribute abnormal development.

Language: Английский

Citations

0
The quality of human eggs and its pre‐IVF incubation DOI Creative Commons
Ri‐Cheng Chian, Yi Guan, Xiaojin He

et al.

Reproductive Medicine and Biology, Journal Year: 2025, Volume and Issue: 24(1)

Published: Jan. 1, 2025

Abstract Background Multi‐factors influence the success rate of infertility treatments, and one important points is to obtain good quality eggs. Methods Based on literatures unpublished data, factors affecting egg were summarized. Main Findings (Results) Egg an determinant in successful treatment. In addition maternal age, controlled ovarian hyperstimulation (COH) protocols also play a key role egg. After retrieval, insemination occurs 3–6 h after collection, with pre‐IVF incubation time by vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) (39–42 post‐HCG injection). The refers short period 3 6 oocyte retrieval before IVF ICSI. collected eggs designed culture medium improves terms maturation early embryonic development. Conclusions Pre‐IVF contributes improvement eggs; therefore, it may increase subsequent pregnancy implantation rates following embryo transfer.

Language: Английский

Citations

0
A complex systems approach to mosaic loss of the Y chromosome DOI
Xihan Guo, Xueqin Dai

GeroScience, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

Language: Английский

Citations

0
Three-dimensional memory of nuclear organization through cell cycles DOI Creative Commons
Shin Fujishiro, Masaki Sasai

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 25, 2024

The genome in the cell nucleus is organized by a dynamic process influenced structural memory from mitosis. In this study, we develop model of human dynamics through cycles extending previously developed whole-genome to cover mitotic phase. With extension, focus on role and cycle organization. simulation progresses mitosis interphase subsequent mitosis, leading successive cycles. During our describes microtubule dynamics, showing how forces orchestrate assembly chromosomes into rosette ring structure at metaphase. explains positioning depends their size metaphase configuration persists dimensions perpendicular division axis, effectively guiding distribution chromosome territories over multiple At onset each G1 phase, phase separation active inactive chromatin domains occurs, A/B compartmentalization. Our cycling simulations show that compartments are unaffected previous consistently established cycle. study highlights interplay between across cycles, providing new perspective for analyses cellular processes.

Language: Английский

Citations

0