Mastrevirus (taxid:10812)

VIRION

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Non-enveloped, about 38 nm in length and 22 nm in diameter (for MSV), twinned (geminate) incomplete T=1 icosahedral symmetry capsid that contains 22 pentameric capsomers made of 110 capsid proteins (CP). Each geminate particle contains only a single circular ssDNA.

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GENOME

Monopartite, circular, ssDNA genome (+) genome of about 2.6-2.8 kb. 3' terminus has no poly(A) tract. There are coding regions in both the virion (positive) and complementary (negative) sense strands.
The genome is replicated through double-stranded intermediates. The replication (Rep) protein initiates and terminates rolling circle replication, the host DNA polymerase being used for DNA replication itself. There is a potential stem-loop structure in the long intergenic region (LIR) that includes a conserved nona-nucleotide sequence (TAATATTAC) where ssDNA synthesis is initiated.
The short intergenic region (SIR) contains bidirectional polyadenylation signals.

GENE EXPRESSION

Transcription is bidirectional from the long intergenic region (LIR) which contains two divergent promoters: a V-(virion) and a C-(complementary) sense. The resulting C- and V-transcripts encode four proteins. On the V-sense: the movement and CP. On the C-sense: RepA and Rep (which is expressed as a splice product of RepA and RepB ORFs).

ENZYMES

REPLICATION

NUCLEAR

  1. Virus penetrates into the host cell.
  2. Uncoating, the viral ssDNA genome penetrates into the nucleus.
  3. The ssDNA is converted into dsDNA with the participation of cellular factors.
  4. bidirectional dsDNA transcription from the IR promoter produces viral mRNAs and translation of viral proteins.
  5. Replication is initiated by cleavage of the(+)strand by REP, and occurs by rolling circle producing ssDNA genomes.
  6. These newly synthesized ssDNA can either
    a) be converted to dsDNA and serve as a template for transcription/replication
    b) be encapsidated by capsid protein and form virions released by cell lysis
    c) be transported outside the nucleus, to a neighboring cell through plasmodesmata (cell-cell movement) with the help of viral movement proteins.

Host-virus interaction

Cell-cycle modulation

Mastrevirus protein RepA is responsible for inhibiting host retinoblastoma protein and inducing transition from the G1 to S phase in preparation for virus replication since the virus targets differentiated non-dividing cells. .

Matching UniProtKB/Swiss-Prot entries

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

55 entries grouped by strain

4 entries

Bean yellow dwarf virus (BeYDV) reference strain

Select_allDeselect_all
REPA_BEYDV Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_BEYDV Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
MP_BEYDV Movement protein (MP)
CAPSD_BEYDV Capsid protein (Coat protein) (CP)

4 entries

Maize streak virus genotype A (isolate Kenya) (MSV) reference strain

Select_allDeselect_all
REPA_MSVK Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_MSVK Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
CAPSD_MSVK Capsid protein (Coat protein) (CP)
MP_MSVK Movement protein (MP)

4 entries

Maize streak virus genotype A (isolate South Africa) (MSV) reference strain

Select_allDeselect_all
REP_MSVS Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_MSVS Replication-associated protein A (RepA) (EC 3.1.21.-)
CAPSD_MSVS Capsid protein (Coat protein) (CP)
MP_MSVS Movement protein (MP)

4 entries

Maize streak virus genotype D (isolate Raw) (MSV) reference strain

Select_allDeselect_all
REPA_MSVRA Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_MSVRA Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
CAPSD_MSVRA Capsid protein (Coat protein) (CP)
MP_MSVRA Movement protein (MP)

4 entries

Miscanthus streak virus (isolate 91) (MiSV) reference strain

Select_allDeselect_all
REP_MISV9 Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_MISV9 Replication-associated protein A (RepA) (EC 3.1.21.-)
CAPSD_MISV9 Capsid protein (Coat protein) (CP)
MP_MISV9 Putative movement protein (MP)

4 entries

Panicum streak virus (isolate Kenya) (PanSV) reference strain

Select_allDeselect_all
REP_PASVK Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_PASVK Replication-associated protein A (RepA) (EC 3.1.21.-)
CAPSD_PASVK Capsid protein (Coat protein) (CP)
MP_PASVK Movement protein (MP)

4 entries

Sugarcane streak virus (isolate South Africa) (SSV) (Sugarcane streak virus (isolate Natal)) reference strain

Select_allDeselect_all
REP_SSVN Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_SSVN Replication-associated protein A (RepA) (EC 3.1.21.-)
MP_SSVN Movement protein (MP)
CAPSD_SSVN Capsid protein (Coat protein) (CP)

4 entries

Wheat dwarf virus (isolate Sweden) (WDV) reference strain

Select_allDeselect_all
REPA_WDVS Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_WDVS Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
MP_WDVS Movement protein (MP)
CAPSD_WDVS Capsid protein (Coat protein) (CP)

3 entries

Chloris striate mosaic virus (CSMV) reference strain

Select_allDeselect_all
REP_CSMV Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_CSMV Replication-associated protein A (RepA) (EC 3.1.21.-)
CAPSD_CSMV Capsid protein (Coat protein) (CP)

4 entries

Maize streak virus genotype A (isolate Nigeria) (MSV)

Select_allDeselect_all
REP_MSVN Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_MSVN Replication-associated protein A (RepA) (EC 3.1.21.-)
CAPSD_MSVN Capsid protein (Coat protein) (CP)
MP_MSVN Movement protein (MP)

4 entries

Maize streak virus genotype B (isolate Tas) (MSV)

Select_allDeselect_all
REPA_MSVTA Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_MSVTA Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
CAPSD_MSVTA Capsid protein (Coat protein) (CP)
MP_MSVTA Movement protein (MP)

4 entries

Maize streak virus genotype C (isolate Set) (MSV)

Select_allDeselect_all
REP_MSVSE Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
REPA_MSVSE Replication-associated protein A (RepA) (EC 3.1.21.-)
MP_MSVSE Movement protein (MP)
CAPSD_MSVSE Capsid protein (Coat protein) (CP)

4 entries

Maize streak virus genotype E (isolate Pat) (MSV)

Select_allDeselect_all
REPA_MSVPA Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_MSVPA Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
CAPSD_MSVPA Capsid protein (Coat protein) (CP)
MP_MSVPA Movement protein (MP)

4 entries

Tobacco yellow dwarf virus (strain Australia) (TYDV)

Select_allDeselect_all
REPA_TYDVA Replication-associated protein A (RepA) (EC 3.1.21.-)
REP_TYDVA Replication-associated protein (Rep) (EC 2.7.7.-) (EC 3.1.21.-)
CAPSD_TYDVA Capsid protein (Coat protein) (CP)
MP_TYDVA Movement protein (MP)