Roseolovirus (taxid:40272)
VIRION

Enveloped, spherical to pleomorphic, 150-200 nm in diameter, T=16 icosahedral symmetry. Capsid consists of 162 capsomers and is surrounded by an amorphous tegument. Glycoproteins complexes are embedded in the lipid envelope.
GENOME
Monopartite, linear, dsDNA genome of about 200 kb. The genome contains terminal and internal reiterated sequences.
GENE EXPRESSION
Each viral transcript usually encodes a single protein and has a promoter/regulatory sequence, a TATA box, a transcription initiation site, a 5' leader sequence of 30-300 bp (not translated), a 3' untranslated sequence of 10-30 bp, and a poly A signal. There are many gene overlaps. There are only few spliced genes. Some of the expressed ORFs are antisense to each other. Some ORFs can be accessed from more than one promoter. There are some non-coding genes.
ENZYMES
- DNA-dependent DNA polymerase
- DNA primase
- Tegument deneddylase (Peptidase C76)
- Assemblin (Peptidase S21)
- Kinase
- Helicase
- Ribonucleoside-diphosphate reductase
- Uracil-DNA glycosylase
REPLICATION
NUCLEAR
Lytic replication:
- Attachment of the viral glycoproteins to host receptors mediates endocytosis of the virus into the host cell.
- Entry into host cell is still unclear and may depend on the host cell type, i.e. endocytosis versus fusion at the plasma membrane.
- The capsid is transported to the nuclear pore where the viral DNA is released into the nucleus.
- Occasionally, the viral genome can be integrated in host chromosome thereby creating a latent virus.
- Transcription of immediate early genes which promote transcription of early genes and protect the virus against innate host immunity.
- Transcription of early viral mRNA by host polymerase II, encoding proteins involved in replication of the viral DNA.
- A first round of circular genome amplification occurs by bidirectional replication
- Synthesis of linear concatemer copies of viral DNA by rolling circle.
- Transcription of late mRNAs by host polymerase II, encoding structural proteins.
- Assembly of the virus in nuclear viral factories and budding through the inner lamella of the nuclear membrane which has been modified by the insertion of herpes glycoproteins, throughout the Golgi and final release at the plasma membrane.
Latent replication : replication of circular viral episome in tandem with the host cell DNA using the host cell replication machinery.
Host-virus interaction
Adaptive immune response inhibition
The HHV-6 U24 protein downregulates the T-cell receptor complex and impairs T-cell activation.
Cell-cycle modulation
The UL24 protein homolog induces a cell cycle arrest at G2/M transition through inactivation of the host cyclinB/cdc2 complex .
Innate immune response inhibition
HHV-6 protein IE1 interferes with the binding of IRF3 to the IFN-beta promoter, reduces levels of dimerized IRF3 and nucleus-translocated IRF3 in response to activation by TBK1. This inhibiton of the pathway through IRF3 subsequenty prevents the expression IFN-beta.
Host splicing inhibition
HHV-6 UL42 modulates the host mRNA expression by exporting unspliced mRNA, thereby inducing alternative splicing .
Matching UniProtKB/Swiss-Prot entries
(all links/actions below point to uniprot.org website)283 entries grouped by protein
3 entries
Alkaline nuclease (EC 3.1.-.-)
1 entry
Protein B1
1 entry
Protein B2
1 entry
Protein B3
1 entry
Protein B4
1 entry
Protein B5
1 entry
Protein B6
1 entry
Protein B7
1 entry
Protein B8
1 entry
Protein B9
2 entries
Putative CC-type chemokine U83
3 entries
Cytoplasmic envelopment protein 1
3 entries
Cytoplasmic envelopment protein 2
3 entries
Cytoplasmic envelopment protein 3
3 entries
Capsid vertex component 1
3 entries
Capsid vertex component 2
3 entries
Major DNA-binding protein
3 entries
DNA polymerase catalytic subunit (EC 2.7.7.7)
2 entries
Uncharacterized protein DR1
1 entry
Uncharacterized protein DR2
2 entries
Uncharacterized protein DR3
1 entry
Uncharacterized protein DR4
1 entry
Uncharacterized protein DR5
2 entries
G2/M cell-cycle inhibitor DR6
1 entry
Transactivator protein DR7
1 entry
Uncharacterized protein DR8
4 entries
Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) (EC 3.6.1.23) (dUTP pyrophosphatase)
4 entries
Envelope glycoprotein B (gB)
3 entries
Probable ganciclovir kinase (EC 2.7.1.-)
4 entries
Envelope glycoprotein H (gH)
3 entries
Envelope glycoprotein L (gL)
3 entries
Envelope glycoprotein M (gM)
3 entries
Envelope glycoprotein N
4 entries
120 kDa Glycoprotein O (gO-120K) (Glycoprotein U47)
1 entry
Glycoprotein 105 (gp105)
2 entries
Glycoprotein Q1 (gQ1) (Glycoprotein 105) (gp105) (Glycoprotein Q-80k) (gQ-80k) (HCLF1 protein)
2 entries
Glycoprotein Q2 (gQ2)
3 entries
DNA replication helicase (EC 3.6.4.-)
3 entries
DNA helicase/primase complex-associated protein (HEPA) (Primase-associated factor)
3 entries
mRNA export factor ICP27 homolog
1 entry
Immediate-early protein 1 (IE1) (Protein RF2/RF3/RF4) (pRF2/pRF3/pRF4)
3 entries
Immediate-early protein 2 (IE2)
3 entries
Inner tegument protein
4 entries
Large tegument protein deneddylase (EC 3.4.19.12) (EC 3.4.22.-)
3 entries
Major capsid protein (MCP)
4 entries
Nuclear egress protein 1
3 entries
Nuclear egress protein 2
3 entries
Replication origin-binding protein (OBP)
2 entries
Putative OX-2 membrane glycoprotein homolog (Protein U85)
4 entries
Large structural phosphoprotein (100 kDa phosphoprotein) (pp100) (Major antigenic structural protein)
3 entries
Portal protein
2 entries
Phosphoprotein 85 (pp85) (Protein U14)
3 entries
DNA primase (EC 2.7.7.-)
3 entries
Ribonucleoside-diphosphate reductase large subunit-like protein
1 entry
Protein RJ1 (Protein LT1)
3 entries
Capsid scaffolding protein (Capsid protein P40) (Protease precursor) (pPR)
3 entries
Small capsomere-interacting protein
3 entries
Tegument protein UL51 homolog
3 entries
Tripartite terminase subunit 1
2 entries
Tripartite terminase subunit 2
3 entries
Tripartite terminase subunit 3 (EC 3.1.-.-) (Terminase large subunit)
4 entries
Triplex capsid protein 1
4 entries
Triplex capsid protein 2
3 entries
Protein U10
2 entries
Uncharacterized protein U13
2 entries
Protein U15
2 entries
Protein U17/U16
3 entries
Protein U17
3 entries
Putative immediate early glycoprotein (Protein U18)
2 entries
Glycoprotein U20
4 entries
U21 glycoprotein
2 entries
Glycoprotein U22
2 entries
Glycoprotein U23
3 entries
U24 protein
1 entry
Uncharacterized protein U24A
2 entries
Uncharacterized protein U6
1 entry
Uncharacterized protein U61
1 entry
Protein U7
1 entry
Uncharacterized protein U78
4 entries
Protein U79
1 entry
Protein U8
1 entry
Protein U9
1 entry
Protein U90
2 entries
Protein U91
2 entries
Uncharacterized protein U95
4 entries
Protein UL24 homolog
3 entries
Packaging protein UL32
2 entries
G-protein coupled receptor homolog U12
2 entries
Apoptosis inhibitor U19
3 entries
Protein U33
3 entries
Protein U52
3 entries
Protein U58
3 entries
Protein U59
3 entries
Protein U62
3 entries
Protein U63
4 entries
Protein U67
3 entries
Protein U68
3 entries
Uracil-DNA glycosylase (UDG) (EC 3.2.2.27) (UNG)
1 entry
Uncharacterized protein U55A
1 entry
Uncharacterized protein U55B
1 entry
G-protein coupled receptor
3 entries
DNA polymerase processivity factor (Phosphoprotein P41) (PP41) (Polymerase accessory protein) (PAP)
1 entry
Protein U1
1 entry
U10 protein
1 entry
Protein U2
4 entries
Protein U25
5 entries
Protein U26
3 entries
Protein U3
3 entries
Protein U4
1 entry
Protein U5
3 entries
G-protein coupled receptor homolog U51
3 entries
Protein U54
2 entries
Uncharacterized protein U55
1 entry
Protein U7
2 entries
Protein U8
3 entries
Protein U84
2 entries
Protein U9
3 entries
Protein U94
Human betaherpesvirus 6A taxid:32603
Human betaherpesvirus 7 taxid:10372
Human herpesvirus 6A (strain GS) taxid:10369
Protein | ModelArchive |
Envelope glycoprotein H (gH) | ma-jd-viral-16932 |
Human herpesvirus 6A (strain Uganda-1102) taxid:10370
Human herpesvirus 6B taxid:32604
Human herpesvirus 6B (strain Z29) taxid:36351
Human herpesvirus 7 (strain JI) taxid:57278
Human herpesvirus 7 (strain MUK) taxid:57279
Protein | ModelArchive |
Triplex capsid protein 2 | ma-jd-viral-04783 |
Human herpesvirus 7 (strain RK) taxid:262398
Protein | ModelArchive |
U21 glycoprotein (gp60) | ma-jd-viral-36538 |