Ribosomes, which synthesize the proteins of a cell, comprise ribosomal RNA and ribosomal
proteins, which coassemble hierarchically during a process termed ribosome biogenesis.
Historically, biochemical and molecular biology approaches have revealed how
preribosomal particles form and mature in consecutive steps, starting in the nucleolus and
terminating after nuclear export into the cytoplasm. However, only recently, due to the
revolution in cryo–electron microscopy, could pseudoatomic structures of different …