title: Circularly permuted GTPase YqeH binds 30S ribosomal subunit: Implications for its role in ribosome assembly.
abstract: YqeH, a circularly permuted GTPase, is conserved among bacteria and eukaryotes including humans. It was shown to be essential for the assembly of small ribosomal (30S) subunit in bacteria. However, whether YqeH interacts with 30S ribosome and how it may participate in 30S assembly are not known. Here, using co-sedimentation experiments, we report that YqeH co-associates with 30S ribosome in the GTP-bound form. In order to probe whether YqeH functions as RNA chaperone in 30S assembly, we assayed for strand dissociation and annealing activity. While YqeH does not exhibit these activities, it binds a non-specific single and double-stranded RNA, which unlike the 30S binding is independent of GTP/GDP binding and does not affect intrinsic GTP hydrolysis rates. Further, S5, a ribosomal protein which participates during the initial stages of 30S assembly, was found to promote GTP hydrolysis and RNA binding activities of YqeH.
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India.
authors.forename: Baskaran
authors.initials: B
authors.lastname: Anand
authors.forename: Parag
authors.initials: P
authors.lastname: Surana
authors.forename: Sagar
authors.initials: S
authors.lastname: Bhogaraju
authors.forename: Sushmita
authors.initials: S
authors.lastname: Pahari
authors.forename: Balaji
authors.initials: B
authors.lastname: Prakash
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology*; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D006868:Hydrolysis; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012330:RNA, Double-Stranded / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism; D054680:Ribosome Subunits, Small, Bacterial / Q000378:metabolism*
chemical_list: D018832:Molecular Chaperones; D012330:RNA, Double-Stranded; D012269:Ribosomal Proteins; C030831:ribosomal protein S5; D006160:Guanosine Triphosphate; D020558:GTP Phosphohydrolases