Vl 2 Trypanosoma brucei II Flashcards
1
Q
Describe the mechanism of trans-splicing in Trypanosoma brucei
A
- combines two separate pre-mRNA molecules to form a chimeric non-co-linear RNA⇒ may exert a function distinct from its original molecules (encode novel proteins/ have regulatory functions) ⇒ increase complexity of proteome
- all mRNA in Trypanosoma have the same 39-nt sequence on the 5´end (splice leader RNA that get’s its intron cleaved first, which then binds to receiver pre-mRNA)
2
Q
Describe the mechanism of RNA editing in Trypanosoma brucei
A
- post-transcriptional insertion or deletion of uridine residues where frameshifts in the pre-edited mRNA occurred
- directed by a diverse family of small, guide RNAs (gRNAs).
- gRNAs are independent transcriptions units and are encoded on mini-circles.
3
Q
How is sleeping sickness treated and controlled?
A
- Chemotherapy with toxic components:
DFMO, Suramin (both enzyme inhibitors), Melarsoprol, Pentamidin, Eflornithin (vs fast replicating cells)
vector control with attractants and insecticides impregnated blue traps
4
Q
What are unique features of the vector of sleeping sickness and
how can that be exploited for national control programs?
A
- viviparous - only stage 3 larvae born (rest happens inside mother) ⇒ only 1 offspring at once
⇒ population relatively stable (doesnt quickly jump back up after killing them with insecticides) - only copulate once: females store male sperm⇒ release infertile males for vector control
- can’t see stripes ⇒ zebras are safe
- they REALLY like dark blue ⇒ set up blue traps with attractants and insecticides to catch them
