Dynamic interplay between human alpha-satellite DNA structure and centromere functions

Area of Science:

• Genetics
• Molecular Biology
• Epigenetics

Background:

• Centromeres are crucial for genome stability and chromosome segregation.
• Human centromeres comprise repetitive alpha-satellite DNA organized into higher-order repeats (HORs).
• Epigenetic specification by CENP-A is vital for kinetochore assembly and microtubule attachment.

Purpose of the Study:

• To review evidence of meiotic selection mitigating centromere drive.
• To discuss recent findings on centromere damage, recombination, and repair during mitosis.
• To propose an antagonistic pleiotropy model for centromere DNA instability.

Main Methods:

• Literature review of centromere biology, DNA repair, and meiotic selection.
• Analysis of existing data on centromere sequence instability and its consequences.
• Conceptual framework development for centromere-kinetochore interactions.

Main Results:

• Centromeric DNA is typically inherited intact but exhibits instability and recombination outside meiosis.
• Meiotic selection acts to counteract centromere drive.
• Centromere instability can drive aneuploidy and degenerative diseases.

Conclusions:

• Centromere DNA instability presents an antagonistic pleiotropy, being both detrimental (aneuploidy) and potentially necessary (HOR homogenization).
• A framework is proposed to link DNA instability, chromatin, and structural changes to functional consequences.
• Understanding centromere malfunction is key to addressing chromosome integrity disorders.