Effect of magnesium ions on the thermal stability of human poly(A)-specific ribonuclease.
Poly(A)-specific ribonuclease (PARN), a member of the DEDD family, is a key enzyme involved in the deadenylation of mRNA in higher eukaryotic cells. In this research, it was found that Mg(2+) could protect PARN against thermal inactivation by increasing the midpoint of inactivation and decreasing the inactivation rate. This protective effect was unique to Mg(2+) in a concentration-dependent manner. However, the thermal unfolding and aggregation was promoted by the addition of Mg(2+) at high temperatures. These results revealed that Mg(2+) might have dual effects on PARN stability: protecting the active site but endangering the overall structural stability.
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
Cheng
Yuan
Y
Zhou
Hai-Meng
HM
Yan
Yong-Bin
YB
D020134:Catalytic Domain; D002413:Cations, Divalent / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D005095:Exoribonucleases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D013816:Thermodynamics
D002413:Cations, Divalent; D005095:Exoribonucleases; D008274:Magnesium; D011994:Recombinant Proteins