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[Nov. 10] 97th IRCMS Seminar

October 30 2023

We would like to inform you that the 97th IRCMS seminar has been scheduled as below.
* This IRCMS seminar is open to everyone.

Date      : November 10, 2023 (Friday)

Time      : 16:30-17:30

ZOOM : Meeting ID: 845 2917 0099
              Passcode: ircmsSem11

Speaker : Dr. Takashi Mikawa (University of California San Francisco)


Title        :  Distance between Homologous Chromosomes

Abstract :

In meiosis, pairing of homologous chromosomes is essential for securing genetic diversity among germ cells through recombination. In somatic cells, however, close proximity between homologous chromosome could cause several problems, such as transcriptional interference as well as accidental homologous recombination leading to the loss of heterozygosity. Regulation of distance between homologous chromosomes is one of least understood processes in chromosome biology.The current dogma assumes that maternal and paternal chromosomes are randomly positions at the interphase as well as during mitosis. Our analysis of chromosome positions in human endothelial cells has suggested that maternally derived haploid set and paternally derived one are spatially segregated throughout cell cycle. Potential mechanisms for one haploid chromosome set stay together, thereby keeping homologous chromosomes apart, will be discussed.

(日本語概要)

減数分裂の間相同染色体は物理的にペアをつくり、効率の良い乗り換え交叉を経て生殖細胞間の遺伝情報の多様性を生み出しています。一方脊椎動物の体細胞では、相同染色体はペアをつくらず、物理的距離を保つことで遺伝子発現の干渉や異常な交叉の可能性を減らしているようです。相同染色体間の距離がどのように決められているのかは、染色体生物学のなかで理解の遅れている分野のひとつです。教科書には体細胞の中で母親由来と父親由来の相同染色体が静止期も分裂中もばらばらに分布するように書かれています。私達の研究チームは分裂期の相同染色体の分布の解析から、母親由来と父親由来の相同染色体は物理的に乖離しておりペアをつくらないのではないかと考えるようになりました。今回は、解析を静止期を含め細胞周期を通じて母親由来と父親由来の相同染色体が混じり合わない可能性を示したいと思います。なぜ相同染色体の物理的な乖離が細胞周期をとうして維持できるのかの考察もしたいと思っています。

 

Flyer: (Click to enlarge)

Flyer_97th IRCMS Seminar-1.jpg