How "protein factories" mature

Ribosomes are small "factories" in which proteins are assembled according to genetic construction plans. The maturation of ribosomes, of which every human cell contains up to a million, is a complicated, multi-phase process. Now, with the aid of cryo-electron microscopy, scientists from Heidelberg University and Ludwig-Maximilians-Universität München have been able to clarify an important step in ribosomal formation. These "protein factories" consist of two ribosomal subunits and the scientists have shown that the smaller one "peels out" of a precursor complex and does not break off en bloc, as was so far assumed. The findings were published in the journal "Science". A ribosome is a giant molecule - a complex structure consisting of special proteins and ribonucleic acid (RNA). Yet how the assembly of ribosomes exactly happens is not yet entirely understood.