Table 2. Putative protein-protein interactions of HCMV virion proteins that have not been previously reported and were determined by our YTH and co-IP analysis.
| BD ORFs and Function | AD ORFs and Function | Co-IP | ||
| Capsid Protein-Tegument Protein Interactions | ||||
| UL24* | Tegument protein (NE) | UL46 | Minor capsid protein binding protein (E) | + |
| UL24 | Tegument protein (NE) | UL85 | Minor capsid protein (E) | + |
| Tegument Protein-Tegument Protein Interactions | ||||
| UL24 | Tegument protein (NE) | UL24 | Tegument protein (NE) | − (putative) |
| UL24* | Tegument protein (NE) | UL25 | Tegument protein (NE) | + |
| UL24 | Tegument protein (NE) | UL26 | Transcription (D) | − (putative) |
| UL24* | Tegument protein (NE) | UL32 | Basic phosphoprotein (E) | + |
| UL24* | Tegument protein (NE) | UL43 | Tegument protein (NE) | + |
| UL24 | Tegument protein (NE) | UL51 | DNA packaging/cleavage (E) | − (putative) |
| UL24* | Tegument protein (NE) | UL69 | Transcription (D) | + |
| UL24* | Tegument protein (NE) | UL71 | Unknown function (E) | + |
| UL24 | Tegument protein (NE) | UL88 | Unknown function (D) | − (putative) |
| UL24 | Tegument protein (NE) | UL89.2 | DNA packaging/cleavage (E) | + |
| UL24 | Tegument protein (NE) | US22 | Tegument protein (NE) | − (putative) |
| UL24 | Tegument protein (NE) | US23 | Tegument protein (D) | − (putative) |
| UL25* | Tegument protein (NE) | UL43 | Tegument protein (NE) | + |
| UL25 | Tegument protein (NE) | UL89.2 | DNA packaging/cleavage (E) | + |
| UL32 | Basic phosphoprotein (E) | UL89.2 | DNA packaging/cleavage (E) | − (putative) |
| UL43 | Tegument protein (NE) | UL89.2 | DNA packaging/cleavage | + |
| UL44 | DNA polymerase accessory protein (E) | UL25 | Tegument protein (NE) | + |
| UL45 | Ribonucleotide reductase homologue (NE) | UL24 | Tegument protein (NE) | − (putative) |
| UL45 | Ribonucleotide reductase homologue (NE) | UL26 | Transcription (D) | + |
| UL45 | Ribonucleotide reductase homologue (NE) | UL89.2 | DNA packaging/cleavage (E) | − (putative) |
| UL45 | Ribonucleotide reductase homologue (NE) | US23 | Tegument protein (D) | − (putative) |
| UL54 | DNA polymerase catalytic subunit (E) | UL24 | Tegument protein (NE) | − (putative) |
| UL54 | DNA polymerase catalytic subunit (E) | UL26 | Transcription (D) | − (putative) |
| UL54 | DNA polymerase catalytic subunit (E) | UL89.2 | DNA packaging/cleavage (E) | − (putative) |
| UL69 | Transcription (D) | UL25 | Tegument protein (NE) | − (putative) |
| UL69 | Transcription (D) | UL48N | Tegument protein (E) | + |
| UL69 | Transcription (D) | UL89.2 | DNA packaging/cleavage (E) | − (putative) |
| UL71 | Unknown function (E) | UL26 | Transcription (D) | − (putative) |
| UL71 | Unknown function (E) | UL51 | DNA packaging/cleavage (E) | + |
| UL71 | Unknown function (E) | UL71 | Unknown function (E) | − (putative) |
| UL71 | Unknown function (E) | UL89.2 | DNA packaging/cleavage (E) | + |
| UL72 | Unknown function (D) | UL24 | Tegument protein (NE) | + |
| UL72 | Unknown function (D) | UL26 | Transcription (D) | − (putative) |
| UL72 | Unknown function (D) | UL94 | Tegument Protein (E) | − (putative) |
| UL83 | Tegument (immunomodulation) (NE) | UL25 | Tegument protein (NE) | + |
| UL89.2 | DNA packaging/cleavage (E) | UL89.2 | DNA packaging/cleavage (E) | − (putative) |
| UL103 | Unknown function (D) | UL48N | Tegument protein (E) | − (putative) |
| UL103 | Unknown function (D) | UL103 | Unknown function (D) | − (putative) |
| UL112.1 | Early protein (D) | UL25 | Tegument protein (NE) | − (putative) |
| UL122 | IE-2 (Transcription) (E) | UL25 | Tegument protein (NE) | + |
| UL122 | IE-2 (Transcription) (E) | UL122 | IE-2 (Transcription) (E) | + |
| US24 | Tegument protein (NE) | US23 | Tegument protein (D) | − (putative) |
| Tegument Protein-Envelope Protein Interactions | ||||
| UL24* | Tegument protein (NE) | UL77 | DNA packaging/cleavage (E) | + |
| UL32 | (Tegument) Basic phosphoprotein (E) | UL77 | DNA packaging/cleavage (E) | − (putative) |
| UL38 | Apoptosis Inhibitor (D) | UL24 | Tegument protein (NE) | − (putative) |
| UL38 | Apoptosis Inhibitor (D) | UL89.2 | DNA packaging/cleavage (E) | − (putative) |
| UL43 | Tegument protein (NE) | UL77 | DNA packaging/cleavage (E) | − (putative) |
| UL45 | Ribonucleotide reductase homologue (NE) | UL77 | DNA packaging/cleavage (E) | − (putative) |
| UL50 | Nuclear egress (E) | UL48N | Tegument protein (E) | − (putative) |
| UL50 | Nuclear egress (E) | UL48C | Tegument protein (E) | − (putative) |
| UL54 | DNA polymerase catalytic subunit (E) | UL77 | DNA packaging/cleavage (E) | − (putative) |
| UL69 | Transcription (D) | UL77 | DNA packaging/cleavage (E) | − (putative) |
| UL103 | Unknown function (D) | UL22A | Glycoprotein (D) | − (putative) |
| UL132 | Glycoprotein (D) | UL48N | Tegument protein (E) | + |
| Envelope Protein-Envelope Protein Interactions | ||||
| UL50 | Nuclear egress (E) | UL77 | DNA packaging/cleavage (E) | + |
| UL132 | Glycoprotein (D) | UL22A | Glycoprotein (D) | + |
Interactions marked by an asterisk represent reciprocal interactions. “+” and “−” represent positive or negative interactions identified by co-IP experiments in human cells (co-IP). The ORFs in which deletion results in no viral growth, wildtype-like growth, and significant growth defect in foreskin fibroblasts are marked as “E” (essential), “NE” (non-essential), and “D” (defect) [7].