Morbillivirus
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. Rinderpest virus. Fig. 1 Electron micrograph of a damaged virion; the nucleocapsid can be seen extruded from the envelope. Length of bar (nm): 100
Virion Morphology:
Spherical, pleomorphic
Envelope:
Yes
Diameter (nm):
150–200
Length (nm):
–
Structural components:
Ribonucleoprotein (RNP), spiked envelope
{
Deceased.
C. Tidona, G. Darai (eds.), The Springer Index of Viruses, DOI 10.1007/978-0-387-95919-1, # Springer Science+Business Media, LLC 2011
1128
Morbillivirus
Buoyant density (g/mL):
1.18–1.20
Buoyant density method:
Sucrose gradients
Lipid composition:
Envelope lipids are derived from the cytoplasmic membrane of the host cell
Additional information:
The envelope (derived from host cell) is studded with 8–12 nm spikes; the RNP is about 1 micron in length with a 18–20 nm diameter, a central hole of 5 nm and helical pitch of 5.5–7.0 nm; the RNP has the characteristic herringbone morphology
Genome Nucleic acid:
RNA
Strandedness:
Single-stranded
Polarity:
Negative-sense
Configuration:
Linear
Segment organization:
Segment no. 1 (kb):
15.69–15.89
One segment(s):
15.69–15.89 (kb) total (calculated)
G + C content (%):
40.9–48.0
mRNA Transcripts:
6
Open reading frames:
8 ORFs
Additional information: The P gene is edited to generate mRNAs for the V protein; the C protein is derived by leaky scanning from an overlapping ORF in the P mRNA; the transcription units are separated by the sequence RTTANNRAAAA CTT AGGRNBMARG (+sense)
Replication Entry mechanism:
Receptor-mediated fusion with the host cell outer membrane
Site of transcription:
Cytoplasm
Transcriptase:
Viral RNA polymerase complex consisting of P and L proteins
Site of genome replication:
Cytoplasm
Replicase:
Virus encoded RNA-dependent RNA polymerase
Replication intermediate:
Nucleocapsid (RNP) with RNA antigenome (+) polarity
Site of virion assembly:
RNP assembles in cytoplasmic virus factories
Egress mechanism:
Budding from cytoplasmic membrane; RNP travels to patches which contain the M, F, and H proteins
Additional information:
Y-formed nucleocapsids have been observed as replication intermediates
Morbillivirus
VIRION
receptor TRANSCRIPTION
mRNAs
REPLICATION NUCLEUS TRANSLATION TRANS LATION
–
H +
R.E.R.
F
L
Golgi N
P
M
– TRA
secretory vesicle
NSP O
RT
cytoskeleton? BUDDING
. Intracellular replication cycle for non segmented negative strand viruses. Fig. 2
History Year of Event
Event
References
1700–1900 The great cattle plagues in Europe caused by rinderpest virus
Wilkinson L (1984) Medical History 28:129–150
500–600
Earliest description of measles by Al Rhazes
Rhazes A-B (1778) Treatise on the small pox and measles. J Brindley, London
300–400
First descriptions of the cattle plagues caused by Rinderpest virus
Barton A (1956) J Am Veterinary Assoc 129:503–505
1920–1930 Last sporadic outbreaks of rinderpest outside Eurasia Smithcors JF (1956) Vet Med 51:249–256 and Africa 1942
First description of peste des petits ruminants in West Africa
Gargadennec L, Lalane A
