Ebolavirus

Ebolavirus is a genus of ssRNA- viruses in the family Filoviridae that infect mammals. Ebolavirus infection in humans leads to fatal hemorrhagic fever.

Filamentous 970 nm long for Ebolavirus. Diameter is about 80nm.

GENOME

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Negative-stranded RNA linear genome, about 18-19 kb in size. Encodes for seven proteins.

Enzyme:RNA dependent RNA polymerase, RNA guanylyl transferase, mRNA methyltransferase.

GENE EXPRESSION

The viral RNA dependent RNA polymerase binds the encapsidated genome at the leader region, then sequentially transcribes each genes by recognizing start and stop signals flanking viral genes. mRNAs are capped and polyadenylated by the L protein during synthesis.
The primary product of the unedited transcript of GP gene yields a smaller non-structural glycoprotein sGP which is efficiently secreted from infected cells. RNA editing allows expression of full-length GP.

REPLICATION

CYTOPLASMIC

  1. Attachment to host receptors through GP glycoprotein like DC-SIGN and DC-SIGNR
  2. Cellular receptor like HAVCR1(TIM1) binds phosphatidyl serine on virion membrane and a signal is transduced into the cell that trigger the macropinocytosis program by apoptotic mimicry.
  3. The virion enters the cell by Macropinocytosis. In some culture cells, GP glycoprotein can be processed by host Cathepsin L and Cathepsin B into 19kDa GP1. But this processing is not happening in all cells or for all ebolavirus.
  4. GP1 interacts with host NPC1, in late macropinosome and promotes Fusion of virus membrane with the vesicle membrane. The ribonucleocapsid is then released into the cytoplasm.
  5. Sequential transcription, viral mRNAs are capped and polyadenylated by polymerase stuttering in the cytoplasm.
  6. Replication presumably starts when enough nucleoprotein is present to encapsidate neo-synthetized antigenomes and genomes.
  7. The ribonucleocapsid interacts with the matrix protein, and buds via the host ESCRT complexes from the plasma membrane, releasing the virion .

Host-virus interaction

Inhibition of host Interferon induction

Vp35 protein prevents host interferon induction by Inhibition of host IKBKE by virus

Inhibition of host interferon signaling

Vp24 protein block interferon signaling by preventing STAT1 signaling. May act by binding host karyopherin ? proteins, thereby preventing them from transporting the tyrosine-phosphorylated transcription factor STAT1 to the nucleus. May directly bind to STAT1 to prevent its signaling .

Antigenic subvertion

Small Glycoprotein (sGP) is a secreted truncated version of GP that prevent host antibodies anti-GP to effectively neutralize it .

Inhibition of acquired immune response

Ebolavirus may encode for a superantigen, thereby inhibiting Vbeta t cells

Matching UniProtKB/Swiss-Prot entries

(all links/actions below point to uniprot.org website)

62 entries grouped by strain (browse by keywords)

9 entries

Zaire ebolavirus (strain Mayinga-76) (ZEBOV) (Zaire Ebola virus) reference strain

Select_allDeselect_all
NCAP_EBOZM Nucleoprotein (Ebola NP) (eNP) (Nucleocapsid protein) (Protein N)
VSGP_EBOZM Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
VP35_EBOZM Polymerase cofactor VP35 (Ebola VP35) (eVP35)
VP40_EBOZM Matrix protein VP40 (Ebola VP40) (eVP40) (Membrane-associated protein VP40)
L_EBOZM RNA-directed RNA polymerase L (Protein L) (Large structural protein) (Replicase) (Transcriptase) ...
VGP_EBOZM Envelope glycoprotein (GP1,2) (GP) [Cleaved into: Shed GP (GP1,2-delta); GP1; GP2]
VP24_EBOZM Membrane-associated protein VP24 (Ebola VP24) (eVP24)
VP30_EBOZM Transcriptional activator VP30 (Ebola VP30) (eVP30) (Minor nucleoprotein VP30)
VSSGP_EBOZM Super small secreted glycoprotein (SsGP)

9 entries

Reston ebolavirus (strain Philippines-96) (REBOV) (Reston Ebola virus)

Select_allDeselect_all
VGP_EBORE Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
L_EBORE RNA-directed RNA polymerase L (Protein L) (Large structural protein) (Replicase) (Transcriptase) ...
VP24_EBORE Membrane-associated protein VP24 (Reston VP24) (rVP24)
VP30_EBORE Transcriptional activator VP30 (EbolaVP30) (eVP30) (Minor nucleoprotein VP30)
VSGP_EBORE Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
VP40_EBORE Matrix protein VP40 (Ebola VP40) (eVP40) (Membrane-associated protein VP40)
VP35_EBORE Polymerase cofactor VP35
NCAP_EBORE Nucleoprotein (Nucleocapsid protein) (Protein N) (Reston NP) (rNP)
VSSGP_EBORE Super small secreted glycoprotein (SsGP)

9 entries

Reston ebolavirus (strain Reston-89) (REBOV) (Reston Ebola virus)

Select_allDeselect_all
VGP_EBORR Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
L_EBORR RNA-directed RNA polymerase L (Protein L) (Large structural protein) (Replicase) (Transcriptase) ...
VSGP_EBORR Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
VP35_EBORR Polymerase cofactor VP35
NCAP_EBORR Nucleoprotein (Nucleocapsid protein) (Protein N) (Reston NP) (rNP)
VP24_EBORR Membrane-associated protein VP24 (Reston VP24) (rVP24)
VP30_EBORR Transcriptional activator VP30 (EbolaVP30) (eVP30) (Minor nucleoprotein VP30)
VP40_EBORR Matrix protein VP40 (Ebola VP40) (eVP40) (Membrane-associated protein VP40)
VSSGP_EBORR Super small secreted glycoprotein (SsGP)

9 entries

Sudan ebolavirus (strain Human/Uganda/Gulu/2000) (SEBOV) (Sudan Ebola virus)

Select_allDeselect_all
VGP_EBOSU Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
L_EBOSU RNA-directed RNA polymerase L (Protein L) (Large structural protein) (Replicase) (Transcriptase) ...
VP35_EBOSU Polymerase cofactor VP35
VSGP_EBOSU Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
VP24_EBOSU Membrane-associated protein VP24 (Reston VP24) (rVP24)
VP30_EBOSU Transcriptional activator VP30 (EbolaVP30) (eVP30) (Minor nucleoprotein VP30)
VP40_EBOSU Matrix protein VP40 (Ebola VP40) (eVP40) (Membrane-associated protein VP40)
NCAP_EBOSU Nucleoprotein (Nucleocapsid protein) (Protein N)
VSSGP_EBOSU Super small secreted glycoprotein (SsGP)

9 entries

Zaire ebolavirus (strain Kikwit-95) (ZEBOV) (Zaire Ebola virus)

Select_allDeselect_all
VGP_EBOZ5 Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
VSGP_EBOZ5 Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
L_EBOZ5 RNA-directed RNA polymerase L (Protein L) (Large structural protein) (Replicase) (Transcriptase) ...
VP35_EBOZ5 Polymerase cofactor VP35 (Ebola VP35) (eVP35)
VP30_EBOZ5 Transcriptional activator VP30 (EbolaVP30) (eVP30) (Minor nucleoprotein VP30)
VP40_EBOZ5 Matrix protein VP40 (Ebola VP40) (eVP40) (Membrane-associated protein VP40)
NCAP_EBOZ5 Nucleoprotein (Ebola NP) (eNP) (Nucleocapsid protein) (Protein N)
VSSGP_EBOZ5 Super small secreted glycoprotein (SsGP)
VP24_EBOZ5 Membrane-associated protein VP24 (Ebola VP24) (eVP24)

5 entries

Zaire ebolavirus (strain Gabon-94) (ZEBOV) (Zaire Ebola virus)

Select_allDeselect_all
VGP_EBOG4 Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
VP40_EBOG4 Matrix protein VP40 (Ebola VP40) (eVP40) (Membrane-associated protein VP40)
VSGP_EBOG4 Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
NCAP_EBOG4 Nucleoprotein (Ebola NP) (eNP) (Nucleocapsid protein) (Protein N)
VP24_EBOG4 Membrane-associated protein VP24 (Ebola VP24) (eVP24)

3 entries

Sudan ebolavirus (strain Boniface-76) (SEBOV) (Sudan Ebola virus)

Select_allDeselect_all
VGP_EBOSB Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
VSGP_EBOSB Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
NCAP_EBOSB Nucleoprotein (Nucleocapsid protein) (Protein N)

3 entries

Sudan ebolavirus (strain Maleo-79) (SEBOV) (Sudan Ebola virus)

Select_allDeselect_all
VGP_EBOSM Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
VSGP_EBOSM Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...
L_EBOSM RNA-directed RNA polymerase L (Protein L) (Large structural protein) (Replicase) (Transcriptase) ...

2 entries

Reston ebolavirus (strain Siena/Philippine-92) (REBOV) (Reston Ebola virus)

Select_allDeselect_all
VGP_EBORS Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
VSGP_EBORS Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...

2 entries

Tai Forest ebolavirus (strain Cote d'Ivoire-94) (TAFV) (Cote d'Ivoire Ebola virus)

Select_allDeselect_all
VGP_TAFVC Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; GP2-delta]
VSGP_TAFVC Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...

2 entries

Zaire ebolavirus (strain Eckron-76) (ZEBOV) (Zaire Ebola virus)

Select_allDeselect_all
VGP_EBOEC Envelope glycoprotein (GP1,2) (GP) [Cleaved into: GP1; GP2; Shed GP (GP1,2-delta)]
VSGP_EBOEC Pre-small/secreted glycoprotein (pre-sGP) [Cleaved into: Small/secreted glycoprotein (sGP); ...