Ezo squirrel (Provided by Minorukaz Nagahara, Asahikawa Medical University RI Research Facility)

Zoological Society of Japan, Hokkaido Branch, 607th Branch Lecture

Date and timeMonday, July 7, 2025, 4:00 PM
LocationHokkaido University, Faculty of Science, Building No. 5, 8th Floor, Room 813

performer: Dr. Kai Otsuka (Faculty of Advanced Engineering, Tokyo University of Science)

TitlePotential functions of KRAB zinc-finger proteins in murine spermatogenesis

AbstractMore than half of the mammalian genome consists of transposable elements (TEs) which originated from retroviral invasions into ancestral genomes during evolution. TEs pose a potential risk for the host genome, as their transposition can disrupt endogenous genes and regulatory elements. To counteract this threat, host cells, especially germ cells, have developed a multi-layer defensive system against retroviruses, including piRNAs, DNA methylation, and other epigenetic machinery, to safeguard genome integrity.
Recently, we discovered that KRAB zinc-finger proteins (KZFPs), the most rapidly evolving transcription factors, bind to evolutionarily young TEs and serve repressive epigenetic marks, H3K9me3, in spermatogonia, suggesting an additional layer of genome surveillance against TEs during male germline development. Furthermore, our analysis uncovered a co-evolutionary relationship between KZFPs and their target TEs, implying that a co-opting arms race takes place in germlines in mammalian evolution.
To further investigate the biological roles of KZFPs in male germline development, we newly generated mouse models harboring deletions of multiple KZFPs-clusters. In this seminar, I will present our recent data from these mutants and discuss the biological significance of KZFPs in male germ cell development.

caretaker：
Atsushi Kimura (Faculty of Science, Hokkaido University)