G0/G1 host cell cycle checkpoint dysregulation by virus

Host cell cycle is a highly regulated process during which chromosomes duplicated and cell division occurs. Resting cells that are not dividing are in a phase called G0. During division, the cell undergoes 4 distinct stages termed G1, S, G2, and M (mitosis). These periods of activity are separated by regulatory checkpoints at major transition phases. These checkpoints include G0/G1 which regulates the entry of a quiescent cell back into the cycle, G1/S, and G2/M.

Some viruses have evolved strategies to induce cell cycle entry in resting cells by promoting the G0/G1 checkpoint transition. For example, myxomavirus M-T5 mediates cell cycle progression beyond the G0/G1 checkpoint, with increased phosphorylation, ubiquitination and degradation of the cyclin-dependent kinase inhibitor p27/KIP1. HTLV-1 Tax induces also a cell cycle progression from G0/G1 phase.

Other viruses benefit from stopping host cells in G0/G1 checkpoint. For example SARS protein 3a inhibits Rb phosphorylation and blocks cell cycle progression at the G0/G1 phase. Epstein-Barr virus BZLF1 (Zta) mediates a G0/G1 growth arrest correlated with a p21 induction. Murine coronavirus p28 expression results in an accumulation of hypophosphorylated Rb and cyclin-dependent kinase (Cdk) inhibitor p21.

Matching UniProtKB/Swiss-Prot entries

28 entries grouped by strain (browse by keywords)

2 entries

Human cytomegalovirus (strain Merlin) (HHV-5) (Human herpesvirus 5) reference strain

Select_allDeselect_all
VIE2_HCMVM Viral transcription factor IE2 (IE2) (Protein UL122)
UL27_HCMVM Protein UL27

2 entries

Severe acute respiratory syndrome coronavirus (SARS-CoV) reference strain

Select_allDeselect_all
NS3B_SARS ORF3b protein (Accessory protein 3b) (Non-structural protein 3b) (ns3b) (Protein X2)
NS7A_SARS ORF7a protein (Accessory protein 7a) (Protein U122) (Protein X4)

1 entry

Bat coronavirus 133/2005 (BtCoV) (BtCoV/133/2005) reference strain

NS3B_BC133 Non-structural protein 3b (ns3b) (Accessory protein 3b)

1 entry

Bat coronavirus 279/2005 (BtCoV) (BtCoV/279/2005) reference strain

NS7A_BC279 Protein 7a (Accessory protein 7a)

1 entry

Bat coronavirus HKU4 (BtCoV) (BtCoV/HKU4/2004) reference strain

NS3B_BCHK4 Non-structural protein 3b (ns3b) (Accessory protein 3b)

1 entry

Bat coronavirus HKU5 (BtCoV) (BtCoV/HKU5/2004) reference strain

NS3B_BCHK5 Non-structural protein 3b (ns3b) (Accessory protein 3b)

1 entry

Bat coronavirus HKU9 (BtCoV) (BtCoV/HKU9) reference strain

NS7A_BCHK9 Non-structural protein 7a (ns7a) (Accessory protein 7a)

1 entry

Epstein-Barr virus (strain AG876) (HHV-4) (Human herpesvirus 4) reference strain

BZLF1_EBVA8 Trans-activator protein BZLF1 (EB1) (Zebra)

1 entry

Epstein-Barr virus (strain B95-8) (HHV-4) (Human herpesvirus 4) reference strain

BZLF1_EBVB9 Trans-activator protein BZLF1 (EB1) (Zebra)

1 entry

Human T-cell leukemia virus 1 (isolate Caribbea HS-35 subtype A) (HTLV-1) reference strain

TAX_HTL1C Protein Tax-1 (Protein X-LOR) (Protein PX) (Trans-activating transcriptional regulatory protein of ...

1 entry

Human T-cell leukemia virus 1 (strain Japan ATK-1 subtype A) (HTLV-1) reference strain

TAX_HTL1A Protein Tax-1 (Protein X-LOR) (Protein PX) (Trans-activating transcriptional regulatory protein of ...

1 entry

Human T-cell leukemia virus 2 (HTLV-2) reference strain

TAX_HTLV2 Protein Tax-2 (Trans-activating transcriptional regulatory protein of HTLV-2)

1 entry

Human T-cell leukemia virus 3 (strain 2026ND) (HTLV-3) reference strain

TAX_HTL32 Protein Tax-3 (Trans-activating transcriptional regulatory protein of HTLV-3)

1 entry

Human T-cell leukemia virus 3 (strain Pyl43) (HTLV-3) reference strain

TAX_HTL3P Protein Tax-3 (Trans-activating transcriptional regulatory protein of HTLV-3)

1 entry

Human cytomegalovirus (strain AD169) (HHV-5) (Human herpesvirus 5) reference strain

VIE2_HCMVA Viral transcription factor IE2 (IE2) (Protein UL122)

1 entry

Murid herpesvirus 1 (strain Smith) (MuHV-1) (Mouse cytomegalovirus) reference strain

VIE2_MUHVS Immediate-early protein 2 (IE2)

1 entry

Myxoma virus (strain Lausanne) (MYXV) reference strain

MT5_MYXVL Ankyrin repeat domain-containing protein M-T5 (M-T5 protein) (M5)

1 entry

Severe acute respiratory syndrome coronavirus 2 (2019-nCoV) (SARS-CoV-2) reference strain

NS7A_SARS2 ORF7a protein (ORF7a) (Accessory protein 7a) (Protein U122) (Protein X4)

2 entries

Human cytomegalovirus (strain Towne) (HHV-5) (Human herpesvirus 5)

Select_allDeselect_all
IE247_HCMVT 45 kDa immediate-early protein 2 (IE2)
VIE2_HCMVT Viral transcription factor IE2 (IE2) (Protein UL122)

1 entry

Bat coronavirus HKU3 (BtCoV) (SARS-like coronavirus HKU3)

NS7A_BCHK3 Protein 7a (Accessory protein 7a)

1 entry

Bat coronavirus Rp3/2004 (BtCoV/Rp3/2004) (SARS-like coronavirus Rp3)

NS7A_BCRP3 Protein 7a (Accessory protein 7a)

1 entry

Epstein-Barr virus (strain GD1) (HHV-4) (Human herpesvirus 4)

BZLF1_EBVG Trans-activator protein BZLF1 (EB1) (Zebra)

1 entry

Human T-cell leukemia virus 1 (isolate Melanesia mel5 subtype C) (HTLV-1)

TAX_HTL1L Protein Tax-1 (Protein X-LOR) (Trans-activating transcriptional regulatory protein of HTLV-1)

1 entry

Human T-cell leukemia virus 1 (isolate Zaire EL subtype B) (HTLV-1)

TAX_HTL1F Protein Tax-1 (Protein X-LOR) (Trans-activating transcriptional regulatory protein of HTLV-1)

1 entry

Middle East respiratory syndrome-related coronavirus (isolate United Kingdom/H123990006/2012) (MERS-CoV) (Betacoronavirus England 1)

ORF4A_MERS1 Non-structural protein ORF4a (ORF4a)