Dr. Kiyoshi Nagai was a pioneering structural biologist who made significant contributions to our understanding of molecular mechanisms in living systems. Born in Osaka, Japan in 1949, he demonstrated exceptional academic promise from his early years and earned his Doctor of Philosophy at Osaka University where he investigated cooperativity in mammalian hemoglobins. During his graduate studies, he spent 18 months at the MRC Laboratory of Molecular Biology in Cambridge working with Max Perutz, which proved to be a formative experience. Following his four years as an Assistant Professor at Nara Medical School, Japan, he returned to the LMB in 1981 as a postdoctoral researcher, where he would spend the remainder of his distinguished career. He was appointed as a group leader in the Structural Studies division in 1987 and served as joint head of this division from 2001 to 2010 until his untimely death in 2019.
Dr. Nagai pioneered research in several areas of structural and molecular biology with an innovative and imaginative approach that revolutionized experimental methodologies. His early landmark work developed groundbreaking methods to express hemoglobin in bacteria, enabling the production of sufficient eukaryotic proteins for structural biology experiments and allowing precise investigation of how specific amino acid mutations affected protein function. Later, he shifted his focus to RNA-protein complexes, with his major scientific achievement being the elucidation of the spliceosome structure, the complex molecular machine responsible for pre-mRNA splicing in eukaryotes. His 1990 publication of the first crystal structure of the RNA recognition motif of the U1A protein provided critical insights into RNA recognition mechanisms. These structural studies created a comprehensive framework for understanding the fundamental process of gene splicing at the molecular level, which was central to proper gene expression in eukaryotic organisms.
Throughout his career, Dr. Nagai was renowned for his compassionate mentorship and inspirational leadership that nurtured multiple generations of scientists in structural biology. His laboratory's research on the spliceosome culminated in high-resolution cryo-EM structures that illuminated the different stages of the splicing catalysis process, providing unprecedented insights into this essential cellular mechanism. Even following his untimely death in 2019, the intellectual framework he established continues to guide researchers in understanding the intricate mechanisms of gene expression. His colleagues and former students have published tributes highlighting how his brilliantly gifted and dedicated approach to science inspired their own work and fostered a collaborative spirit within the scientific community. The depth and quality of his scientific contributions, coupled with his exemplary personal demeanor, ensure that his legacy endures as a cornerstone in the field of structural biology.
