Structural insights into Elongator function

The eukaryotic Elongator complex was initially identified in yeast as a RNA polymerase II (Pol II) associated transcription elongation factor, although there is accumulating evidence that its main cellular function is the specific modification of uridines at the wobble base position of tRNAs. Elongator complex is built up by six highly conserved subunits and was shown to be involved in a variety of different cellular activities. Here, we summarize structural and functional information on individual Elongator subunits or subcomplexes. On the basis of homology models of the Elp1, Elp2 and Elp3 subunits and the crystal structure of the Elp456 subcomplex, the role of each subunit in Elongator complex assembly and catalytic activity is discussed.

► Elongator introduces specific modifications at the wobble base position of tRNAs. ► Elongator harbors six different subunits (Elp1–6) highly conserved among eukaryotes. ► Each Elongator subunit contributes to complex stability and tRNA modifying activity. ► The Elp456 subcomplex is a hexameric ATPase and bridges two Elp123 subcomplexes. ► Elongator emerges as a global translational regulator of gene expression.