The R3H domain stabilizes poly(A)-specific ribonuclease by stabilizing the RRM domain.
Poly(A)-specific ribonuclease (PARN), a key enzyme involved in eukaryotic mRNA decay, contains one catalytic domain and two RNA-binding domains. Here we found that at least one RNA-binding domain is required for the substrate binding, but not for the catalysis of PARN. The removal of the R3H domain led to a dramatic decrease in PARN stability and a change in the aggregation kinetic regime, while only minor effects were observed for the removal of the RRM domain or both RNA-binding domains. Thus the R3H domain might stabilize PARN by acting as a protector or intermolecular chaperone of the RRM domain.
Liu
Wei-Feng
WF
State Key Laboratory of Biomembrane and Membrane Biotechnology, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China.
Zhang
Ao
A
He
Guang-Jun
GJ
Yan
Yong-Bin
YB
D001483:Base Sequence; D017931:DNA Primers; D004795:Enzyme Stability; D005095:Exoribonucleases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D009154:Mutation; D013056:Spectrophotometry, Ultraviolet
D017931:DNA Primers; D005095:Exoribonucleases; C024843:poly A specific exoribonuclease