Unique tasks for ribosomal paralogues

Long dismissed as molecular understudies, the duplicate ribosomal proteins in yeast actually perform unique functions, say Suzanne Komili, Pamela Silver (Harvard Medical School, Boston, MA), and colleagues. The findings suggest that yeast customize ribosomes for particular tasks.

Yeast harbor numerous duplicate genes. For example, 59 of their 78 ribosomal proteins have doubles that differ by only a few amino acids. For more than a decade, researchers thought that these paralogues were interchangeable, in part because knockouts showed no slowing of growth. However, recent work suggested that some so-called backups can't substitute for their counterparts, prompting Komili and colleagues to ask whether duplicate ribosomal proteins have distinct jobs during translation.

The team found that translation of the protein ASH1 went awry in...