Table 1.
HSV-1 structural proteins and complexes discussed in this review.
| Protein or Complex (Alternate Names) |
Description and Location of Protein(s) |
Functions 1 | Section 2 (Key References) |
|---|---|---|---|
| UL11p/UL16p/UL21p | Complex of tegument proteins localized to TGN. | UL11p is palmitoylated and myristoylated. Complex binds to cytoplasmic tail of gE. Envelopment. |
3.5, 3.6, 4.2 [45,46,47,48,49,50,51] |
| UL17p/UL25p | Capsid penton-associated complex. Forms part of the CVSC. |
Anchors UL36p to the capsid as a UL17p/(UL25p)2 complex. Interacts with VP13/14. |
2 [21,24,31] |
| UL18p/UL38p (VP23/VP19C) | Capsid proteins. | Form VP19c/(VP23)2 triplexes that connect VP5 capsomeres. | 2 [11,14,20,21] |
| UL19p (VP5) | Major capsid protein. | Forms penton and hexon capsomeres. | 2 [14,21] |
| UL34p | Type II membrane protein. | Expression influences cell–cell spread. Component of the UL31p/UL34p nuclear export complex. |
4.2 [12,16,52] |
| UL36p (VP1/2) |
Inner tegument protein. | Foundation for recruitment of outer tegument via VP16. Binds UL37p. Cooperates with UL37p to recruit kinesin-1 and kinesin-2 to capsid. Envelopment. |
2, 3.2, 3.3, 3.5, 3.6, 3.7 [53,54,55,56,57,58,59] |
| UL37p | Inner tegument protein. | Binds UL36p, dystonin and gK/UL20p. Membrane-tethering (possible mimic of cellular MTCs). Cooperates with UL36p to recruit kinesin-1 and kinesin-2 to the capsid. Envelopment. |
2, 3.2, 3.3, 3.5, 4.2 [42,43,44,56,60,61,62] |
| US3p | Serine/threonine kinase. Inner tegument protein. |
MT stabilization and acetylation. Assembly of TNTs. |
2, 3.1, 4.5 [26,28,63,64,65] |
| UL7p/UL51p | Outer tegument protein complex. | May mimic or trigger assembly of cellular ESCRT-III complex. Envelopment. Cell–cell spread. Localizes to focal adhesions. |
3.6, 3.7, 4.2 [66,67,68,69] |
| UL46p (VP11/12) |
Outer tegument protein. | Binds UL48p (VP16). | 3.6 [11] |
| UL47p (VP13/14) |
Outer tegument protein. | Binds UL48p (VP16). Binds CVSC component UL17p. Envelopment. |
3.6 [11,70] |
| UL48p (VP16) |
Outer tegument protein. | Connects UL36p to outer tegument. Binds gH carboxy-terminal tail. Envelopment. |
2, 3.6 [11,34,35,36,71,72,73] |
| UL49p (VP22) |
Outer tegument protein. | MT acetylation, bundling and stabilization. Binds UL48p (VP16), gD, gE, gM. Envelopment. |
2, 3.1, 3.6 [11,74,75,76,77] |
| gB | Type I membrane protein. | Loss of gB and gD reduces envelopment. Required for fusion 3. |
3.3, 3.4, 3.6 [78,79,80,81,82] |
| gD | Type I membrane protein. | Loss of gD and gB or gE/gI reduces envelopment. Binds VP22. Required for fusion 3. |
3.4, 3.6 [80,81,83] |
| gE/gI | Heterodimer of type I membrane proteins. | Loss of gE/gI and gD disrupts envelopment. Sorting of virions to epithelial junctions and into or along axons. Loss of gE/gI and US9p reduces envelopment in neurons. gE binds VP22 and the UL11p/UL16p/UL21p complex. |
3.6, 4 [77,83,84,85,86,87,88,89] |
| gH/gL | Heterodimer of type I membrane protein (gH) with lumenal/extracellular soluble subunit (gL). | Required for fusion 3. Binds UL48p (VP16). |
3.4, 3.6 [35,36,81,90] |
| gK/UL20p | Heterodimer of multi membrane- spanning proteins. |
Regulation of gB/gD/gH/gL-mediated fusion 3. Binds UL37p. Sorting of gD and gH/gL to envelopment site. Envelopment. |
3.4, 3.5, 3.6 [61,90,91,92,93] |
| gM gM/gN |
Multi membrane- spanning protein (gM). Can form complex with type 1 membrane protein gN |
Sorting of gD and gH/gL to envelopment site. Envelopment. |
3.4, 3.6 [90,94,95,96] |
| US9p | Type II membrane protein. | Loss of US9p and gE/gI reduces envelopment in neurons. Sorting of virions into or along axons. |
4 [97,98,99,100] |
1 Known functions relevant to this review. 2 Section(s) of this review where the protein/complex is discussed. 3 Fusion between HSV-1 envelope, or infected cell surface, and uninfected cell.