Sex Chromosome Segregation in Adult Human Cells

Presenter: Angelica Aguilar

Co-Presenter(s):
Jem Morales, Alexa Arce Garcia

Presenter Status: Undergraduate student

Academic Year: 20-21

Semester: Spring

Faculty Mentor: Lisa Hua

Department: Biology

Funding Source/Sponsor: Koret Scholars Program, LSAMP, McNair, Other

Other Funding Source/Program: Phalarope Fund Gaining Ground Graduate School Scholarship, CSUPERB New Investigator Grant, National Science Foundation

Screenshot URL: https://drive.google.com/uc?id=1R41hp9sBIq7lXlz3MAIXXLs-_apX8FeD

Abstract:
Chromosome organization is highly dynamic, and may play an important role during aging. However, research to explore chromosome organization, and its effects during aging are currently limited. It was recently found that pairs of homologous chromosomes are continuously separated at mitosis, and display a haploid (1n) chromosome set organization in human neonatal cells 1. The haploid set (1n), or “anti-pairing,” organization is proposed to prevent, or minimize, homologous pairing. Somatic homologous pairing, unlike meiotic pairing, can be detrimental as it can lead to undesired recombination, and gene misregulation 1, 2.  We employed chromosome painting, confocal fluorescence microscopy, and 3D reconstruction to visualize individual sex chromosomes in human adult endothelial cells (HAECs) to test whether adult cells preserve, and maintain the haploid chromosome set pattern throughout life. Our preliminary data show that a pair of sex chromosomes segregate to individual nuclear hemispheres in HAECs, as defined by the nuclear division axis. Thus, suggesting the presence of haploid set organization is preserved in adults. The findings of our project will aid in the knowledge, and understanding of the fidelity of chromosome organization throughout life.