-ssRNA Flashcards
Briefly describe a very basic -ssRNA virus
RNA is complementary to mRNA
RdRp packaged in virions
Must transcribe mRNA before making proteins
Do -ssRNA viruses have an RdRp in virion?
Yes
Are -ssRNA viruses’ RNA infectious on its own?
No - needs to be transcribed first
What is the first thing that must be done once -ssRNA enters the host cell?
Transcription
Briefly describe -ssRNA life cycles.
Receptor mediated entry Synthesize viral mRNA Synthesize more -ssRNA genomes Synthesize virions Virions bud
What are the two species of family paramyxoviridae we studied in -ssRNA? in what subfamily are they?
Respiratory syncytial virus (RSV) and Human Metapneumovirus (MPV)
Pneumovirinae
What kind of capsid do RSV/MPV have?
Briefly describe the envelope.
Helical
Glycoproteins, fusion proteins, matrix proteins and SH protein
What are syncytia?
Multicucleated cells which result from multiple cell fusions of uninuclear cells.
How do MPV/RSV bud from host?
Buds via ESCRT complex
How does RdRp work?
Scans -ssRNA for transcriptional start signal and goes until stop.
Continues scanning polycistronic -ssRNA until all genes are transcribed.
What kind of infections are RSV and MPV?
Respiratory infections
What clinical features are different between RSV and MPV?
There are no clinical differences in symptom presentation.
-ssRNA is recognized by which receptors?
TLR7, and 3
RIG-I
MDA5
What does RSV G protein bind to?
CX3CR1
What are the differences between APC an T cell induced cytokines between healthy and asthmatic people?
In healthy people there is heightened CCL5 and regular amounts of IL10, IP10, and IFNgamma.
In asthmatic people there is heightened levels of IL10, IP10, and IFN gamma bt lowered CCL5.
