Biomaterial Database

HSV-1 DNA polymerase 3'-5' exonuclease-deficient mutant D368A exhibits severely reduced viral DNA synthesis and polymerase expression. 2018

Jessica L Lawler, and Donald M Coen

1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA.

Herpesviruses, including herpes simplex virus-1, encode and express a DNA polymerase that is required for replication of their dsDNA genomes. The catalytic subunit of this enzyme contains a 3'-5' exonuclease that is involved in proofreading during replication. Although certain mutations that severely impair exonuclease activity are not lethal to the virus, it was reported that virus containing the substitution of alanine for aspartate 368 (D368A), which ablates exonuclease activity, could not be recovered, raising the possibility that this activity is essential for viral replication. To investigate this issue, we produced virus containing this mutation (D368A Pol) using a complementing cell line. D368A Pol virus was unable to form plaques on non-complementing cells. Viral DNA synthesis and polymerase activity were severely inhibited in D368A-infected cells, as was expression of the enzyme, suggesting that effects on polymerase expression rather than on exonuclease activity per se largely explain the lethal phenotype of this mutation.

UI	MeSH Term	Description	Entries
D010948	Viral Plaque Assay	Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.	Bacteriophage Plaque Assay,Assay, Bacteriophage Plaque,Assay, Viral Plaque,Assays, Bacteriophage Plaque,Assays, Viral Plaque,Bacteriophage Plaque Assays,Plaque Assay, Bacteriophage,Plaque Assay, Viral,Plaque Assays, Bacteriophage,Plaque Assays, Viral,Viral Plaque Assays
D004259	DNA-Directed DNA Polymerase	DNA-dependent DNA polymerases found in bacteria, animal and plant cells. During the replication process, these enzymes catalyze the addition of deoxyribonucleotide residues to the end of a DNA strand in the presence of DNA as template-primer. They also possess exonuclease activity and therefore function in DNA repair.	DNA Polymerase,DNA Polymerases,DNA-Dependent DNA Polymerases,DNA Polymerase N3,DNA Dependent DNA Polymerases,DNA Directed DNA Polymerase,DNA Polymerase, DNA-Directed,DNA Polymerases, DNA-Dependent,Polymerase N3, DNA,Polymerase, DNA,Polymerase, DNA-Directed DNA,Polymerases, DNA,Polymerases, DNA-Dependent DNA
D004279	DNA, Viral	Deoxyribonucleic acid that makes up the genetic material of viruses.	Viral DNA
D005090	Exodeoxyribonucleases	A family of enzymes that catalyze the exonucleolytic cleavage of DNA. It includes members of the class EC 3.1.11 that produce 5'-phosphomonoesters as cleavage products.	DNA Exonucleases,Exonucleases, DNA
D014764	Viral Proteins	Proteins found in any species of virus.	Gene Products, Viral,Viral Gene Products,Viral Gene Proteins,Viral Protein,Protein, Viral,Proteins, Viral
D014779	Virus Replication	The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.	Viral Replication,Replication, Viral,Replication, Virus,Replications, Viral,Replications, Virus,Viral Replications,Virus Replications
D015870	Gene Expression	The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.	Expression, Gene,Expressions, Gene,Gene Expressions
D050505	Mutant Proteins	Proteins produced from GENES that have acquired MUTATIONS.	Mutant Protein,Protein, Mutant,Proteins, Mutant
D018259	Herpesvirus 1, Human	The type species of SIMPLEXVIRUS causing most forms of non-genital herpes simplex in humans. Primary infection occurs mainly in infants and young children and then the virus becomes latent in the dorsal root ganglion. It then is periodically reactivated throughout life causing mostly benign conditions.	HSV-1,Herpes Simplex Virus 1,HHV-1,Herpes Simplex Virus Type 1,Herpesvirus 1 (alpha), Human,Human Herpesvirus 1
D019943	Amino Acid Substitution	The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.	Amino Acid Substitutions,Substitution, Amino Acid,Substitutions, Amino Acid