Tethered Domains and Flexible Regions in tRNase ZL, the Long Form of tRNase Z

Authors

Christopher Wilson, CUNY York College
Daryl Ramai, CUNY York College
Dmitri Serjanov, CUNY York College
Neema Lama, CUNY York College
Louis Levinger, CUNY York College
Emmanuel J. Chang, CUNY York CollegeFollow

Document Type

Article

Publication Date

July 2013

Abstract

tRNase Z, a member of the metallo-β-lactamase family, endonucleolytically removes the pre-tRNA 3′ trailer in a step central to tRNA maturation. The short form (tRNase ZS) is the only one found in bacteria and archaebacteria and is also present in some eukaryotes. The homologous long form (tRNase ZL), exclusively found in eukaryotes, consists of related amino- and carboxy-domains, suggesting that tRNase ZL arose from a tandem duplication of tRNase ZS followed by interdependent divergence of the domains. X-ray crystallographic structures of tRNase ZS reveal a flexible arm (FA) extruded from the body of tRNase Z remote from the active site that binds tRNA far from the scissile bond. No tRNase ZL structures have been solved; alternative biophysical studies are therefore needed to illuminate its functional characteristics. Structural analyses of tRNase ZL performed by limited proteolysis, two dimensional gel electrophoresis and mass spectrometry establish stability of the amino and carboxy domains and flexibility of the FA and inter-domain tether, with implications for tRNase ZL function.

Comments

This work was originally published in PLoS ONE, available at doi:10.1371/journal.pone.0066942.