TY - JOUR
T1 - The UL41 protein of herpes simplex virus 1 degrades RNA by endonucleolytic cleavage in absence of other cellular or viral proteins
AU - Taddeo, Brunella
AU - Zhang, Weiran
AU - Roizman, Bernard
PY - 2006/2/21
Y1 - 2006/2/21
N2 - The herpes simplex virus 1 ORF UL41 encodes a protein (virion host shutoff or vhs) associated with selective degradation of mRNA early in infection. Some mRNAs, exemplified by GAPDH or β-actin mRNAs, are degraded rapidly. Others, for example IEX-1 mRNA, are degraded in two stages: whereas the 3′ domain disappears rapidly, a large 5′ domain fragment of the mRNA lingers for several hours. Still a third, exemplified by tristetraprolin mRNA, is not degraded, allowing its protein product to accumulate in infected cells. Here we report the following: (i) a GST-vhs protein produced in Escherichia coli, solubilized and purified to homogeneity acts as bona fide endoribonuclease when tested on in vitro transcribed IEX-1 probes. A GST-vhs protein in which three key vhs amino acids were replaced with alanines, solubilized and purified by the same protocol, had no enzymatic activity. (ii) The number of fragments generated by cleavage of a truncated IEX-1 RNA by vhs appears to be small; the cleavage sites are centered at or near the AU-rich elements located at the 3′ untranslated region of the mRNA. A truncated RNA containing only the IEX-1 coding domain was cleaved numerous times. (iii) In cells infected at high multiplicity and exposed to a large number of particles per cell, the vhs protein accumulated within 3 h after infection, in small uniform cytoplasmic granules raising the possibility that vhs colocalizes with tristerapolin, a protein induced after infection, in structures involved in degradation of RNA.
AB - The herpes simplex virus 1 ORF UL41 encodes a protein (virion host shutoff or vhs) associated with selective degradation of mRNA early in infection. Some mRNAs, exemplified by GAPDH or β-actin mRNAs, are degraded rapidly. Others, for example IEX-1 mRNA, are degraded in two stages: whereas the 3′ domain disappears rapidly, a large 5′ domain fragment of the mRNA lingers for several hours. Still a third, exemplified by tristetraprolin mRNA, is not degraded, allowing its protein product to accumulate in infected cells. Here we report the following: (i) a GST-vhs protein produced in Escherichia coli, solubilized and purified to homogeneity acts as bona fide endoribonuclease when tested on in vitro transcribed IEX-1 probes. A GST-vhs protein in which three key vhs amino acids were replaced with alanines, solubilized and purified by the same protocol, had no enzymatic activity. (ii) The number of fragments generated by cleavage of a truncated IEX-1 RNA by vhs appears to be small; the cleavage sites are centered at or near the AU-rich elements located at the 3′ untranslated region of the mRNA. A truncated RNA containing only the IEX-1 coding domain was cleaved numerous times. (iii) In cells infected at high multiplicity and exposed to a large number of particles per cell, the vhs protein accumulated within 3 h after infection, in small uniform cytoplasmic granules raising the possibility that vhs colocalizes with tristerapolin, a protein induced after infection, in structures involved in degradation of RNA.
KW - Endoribonuclease
KW - Virion host shutoff
KW - mRNA
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U2 - 10.1073/pnas.0510712103
DO - 10.1073/pnas.0510712103
M3 - Article
C2 - 16477041
AN - SCOPUS:33644552729
SN - 0027-8424
VL - 103
SP - 2827
EP - 2832
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 8
ER -