J Bacteriol Virol.  2012 Jun;42(2):162-168. 10.4167/jbv.2012.42.2.162.

Possible Roles of UL112-113 Proteins in Human Cytomegalovirus DNA Replication

• Kim YE
• Ahn JH

• KMID: 1717687
• DOI: http://doi.org/10.4167/jbv.2012.42.2.162

Abstract

DNA replication of human cytomegalovirus (HCMV) is a highly regulated process that requires specific interactions between cis-acting lytic origin of replication (oriLyt) and trans-acting viral proteins. Formation of the replication initiation complex is also regulated by specific interactions among viral replication proteins. HCMV replication proteins include origin-binding proteins, core proteins that work in replication forks, and regulatory proteins that modulate host cell functions. This letter describes intriguing questions regarding how HCMV origin-binding proteins interact with oriLyt to initiate DNA replication and how the regulatory UL112-113 proteins, which are found only in beta-herpesviruses, function to promote viral DNA replication.

Keyword

HCMV; DNA replication; UL112-113

MeSH Terms

Cytomegalovirus
DNA
DNA Replication
DNA, Viral
Humans
Proteins
Replication Origin
Viral Proteins
DNA
DNA, Viral
Proteins
Viral Proteins

Figure

• 

  Figure 1 HCMV-encoded replication proteins, the structure of oriLyt, and a possible role of UL112-113 proteins in the formation of the replication initiation complex. (A) The HCMV genome consisting of unique long (UL) and unique short (US) sequences bound by terminal repeats (a/a', b/b', and c/c') and the position of open reading frames (ORFs) for replication proteins are shown. (B) Schematic of HCMV oriLyt showing the relative position of two essential regions, oriLyt promoter, small replicator transcript (SRT), binding sites for C/EBPα and IE2, a highly pyrimidine-rich sequence (Y-block) and the RNA stem-loop structure. Nucleotide (nt) numbers shown are with reference to the AD169 strain DNA sequence. (C) A possible role of UL112-113 proteins as a mediator between the origin-binding complex and the polymerase complex in the formation of the replication initiation complex.

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