Tadasu Nozaki

Research Area:

Chromosomes are living information media within the cell, integrating digital genetic information
with their physical entity. The processing of this information relies on molecular interactions, thermodynamic fluctuations, and mechanical forces. Our lab is interested in the dynamic mechanisms that define the dual nature of chromosomes.
Major projects in our lab will focus on the following questions:
1. Chromosome dynamics: How do chromosomes move, organize, and interact in the crowded environment of the nucleus and the cell?
2. Algorithms in the cell: How is genetic information efficiently searched and recognized?
3. Evolution of chromosomes: Why and how do chromosome size, number, and shape vary so widely across eukaryotes?
A central focus of our current work is understanding meiotic homolog pairing. During this process, homologous chromosomes (homologs) must search and recognize one another and align precisely and tightly along their entire lengths while avoiding entanglements with unrelated chromosomes. This phenomenon provides one of the clearest demonstrations of the dual nature of chromosomes as both informational and physical entities, and it unites all our lab’s core research interests.
Our current goal is to uncover molecular and physical mechanisms of meiotic homolog pairing across eukaryotes. By combining advanced live-cell imaging with quantitative approaches, we aim to develop a multi-scale, integrated framework that connects molecular-level DNA recombination, chromosome-scale crossover patterning, and nucleus-wide chromosome organization. Chromosomes in plants vary remarkably in their number and size. For example, Haplopappus gracilis and Ornithogalum tenuifolium each have only four chromosomes (2n = 4), while Ophioglossum reticulatum contains over 1000 chromosomes per cell. Furthermore, in certain Trillium species, a single chromosome can carry more than 10 Gb of DNA. Polyploidy is also common among plants. Our lab investigates these intriguing chromosomes to address fundamental questions in chromosome biology.

Representative Publications:

• Tadasu Nozaki, Beth Weiner, Nancy Kleckner. Rapid Homologue Juxtaposition During Meiotic Chromosome Pairing. Nature, 634, 1221–1228, 2024
• Tadasu Nozaki#, Soya Shinkai#, Satoru Ide#, Koichi Higashi#, Sachiko Tamura, Masa A. Shimazoe, Masaki Nakagawa, Yutaka Suzuki, Yasushi Okada, Masaki Sasai, Shuichi Onami, Ken Kurokawa, Shiori Iida, Kazuhiro Maeshima. Condensed but liquid-like domain organization of active chromatin regions in living human cells. Science Advances, 9 (14), 2023 #These authors contributed equally.
• Tadasu Nozaki, Frederick Chang, Beth Weiner, Nancy Kleckner. High temporal resolution 3D live-cell imaging of budding yeast meiosis defines discontinuous actin/telomere-mediated chromosome motion, correlated nuclear envelope deformation and actin filament dynamics. Frontiers in Cell and Developmental Biology, 9, 687132, 2021
• Tadasu Nozaki, Damien F. Hudson, Sachiko Tamura, Kazuhiro Maeshima. Dynamic chromatin folding in the cell. Nuclear Architecture and dynamics, 101-122, 2018 (invited book chapter)
• Tadasu Nozaki, Mai Tanbo, Ryosuke Imai, Ryosuke Nagashima, Sachiko Tamura, Tomomi Tani, Masaru Tomita, Kayo Hibino, Masato T. Kanemaki, Kerstin S. Wendt, Yasushi Okada, Takeharu Nagai, and Kazuhiro Maeshima. Dynamic organization of chromatin domains revealed by super-resolution live-cell imaging. Molecular Cell, 67, 282-293, 2017
• Kazuhiro Maeshima, Ryosuke Imai, Sachiko Tamura, Tadasu Nozaki. Chromatin as dynamic 10-nm fibers. Chromosoma, 123, 225-37, 2014
• Tadasu Nozaki, Ryosuke Imai, Sachiko Tamura, Kazuhiro Maeshima. Single nucleosomeimaging in living human cells. Cytologia, 79, 1-1, 2014
• Tadasu Nozaki, Kazunari Kaizu, Chan-Gi Pack, Sachiko Tamura, Tomomi Tani, Saera Hihara, Takeharu Nagai, Koichi Takahashi, Kazuhiro Maeshima. Flexible and dynamic nucleosome fiberin living mammalian cells. Nucleus, 4, 349-56, 2013