 |
PDBsum entry 4zkd
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Gtp-binding protein
|
PDB id
|
|
|
|
4zkd
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Saccharomyces cerevisiae ski7 is a gtp-Binding protein adopting the characteristic conformation of active translational gtpases.
|
|
|
Authors
|
|
E.Kowalinski,
A.Schuller,
R.Green,
E.Conti.
|
|
|
Ref.
|
|
Structure, 2015,
23,
1336-1343.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Ski7 is a cofactor of the cytoplasmic exosome in budding yeast, functioning in
both mRNA turnover and non-stop decay (NSD), a surveillance pathway that
degrades faulty mRNAs lacking a stop codon. The C-terminal region of Ski7
(Ski7C) shares overall sequence similarity with the translational GTPase
(trGTPase) Hbs1, but whether Ski7 has retained the properties of a trGTPase is
unclear. Here, we report the high-resolution structures of Ski7C bound
to either intact guanosine triphosphate (GTP) or guanosine diphosphate-Pi. The
individual domains of Ski7C adopt the conformation characteristic of active
trGTPases. Furthermore, the nucleotide-binding site of Ski7C shares similar
features compared with active trGTPases, notably the presence of a
characteristic monovalent cation. However, a suboptimal polar residue at the
putative catalytic site and an unusual polar residue that interacts with the
γ-phosphate of GTP distinguish Ski7 from other trGTPases, suggesting it might
function rather as a GTP-binding protein than as a GTP-hydrolyzing enzyme.
|
|
|
|
|
|
|
