
세포 주기와 노화에 따라 염색체 강성이 역동적으로 변화한다. 특히 감수분열 I기 염색체가 체세포 분열 염색체보다 약 10배 더 강하며, 노화에 따라 감수분열 I기 염색체의 강성이 증가한다. 그러나 이러한 변화는 주요 감수분열 특이적 응집단백질들의 영향과는 무관한 것으로 나타났다.


coremsg

The intricate structure of chromosomes is complex, and many aspects of chromosome configuration/organization remain to be fully understood. Measuring chromosome stiffness can provide valuable insights into their structure. However, the nature of chromosome stiffness, whether static or dynamic, remains elusive. In this study, we analyzed chromosome stiffness in MI and MII oocytes. We revealed that MI oocytes had a ten-fold increase in stiffness compared to mitotic chromosomes, whereas chromosome stiffness in MII oocytes was relatively low chromosome. We then investigated the contribution of meiosis-specific cohesin complexes to chromosome stiffness in MI and MII oocytes. Surprisingly, the Young’s modulus of chromosomes from the three meiosis-specific cohesin mutants did not exhibit significant differences compared to the wild type, indicating that these proteins may not play a substantial role in determining chromosome stiffness. Additionally, our findings revealed an age-related increase in chromosome stiffness in MI oocytes. Age correlates with elevated DNA damage levels, so we investigated the impact of etoposide-induced DNA damage on chromosome stiffness, discovering a reduction in stiffness in response to such damage in MI oocytes. Overall, our study underscores the dynamic nature of chromosome stiffness, subject to changes influenced by the cell cycle and age.

### Competing Interest Statement

The authors have declared no competing interest.

세포 주기 및 노화에 따른 마우스 염색체 강성의 변화