Class 6 notes.rtf

2 Pages
Unlock Document

University of Toronto St. George
Molecular Genetics and Microbiology
Richard Brown

Class 6 - October 18, 2012 Kauder and Raccaniello paper Showed that wild-type IRES active in multiple tissues Sabin IRES also active in multiple tissues but to lesser degree in every single tissue Sabin IRES didnt work as well - active in CNS Using newborn mice, Sabin strains able to replicate and kill Guest et al paper IRES activity in focus Different approach than Kauder and Raccaniello several host factors that bind - looking at polypyridmine binding tract protein - it's at low concentration in CNS; a neural version of it called nPTB and binding of PTB to wild-type and Sabin IRES and what affect did that have? nPTB in CNS can bind to Sabin IRES but does not function so binding of PTB is important for efficient translation although nPTB could bind, it didn't confer function Also looked at structure of IRES - single mutation changes structure enough that compromises binding of PTB - map binding site of PTB to IRES and show that and close to 472 position - localized structure change by mutation and this compromises the binding - with Sabin IRES - have compromised binding of PTB and have low levels of PTB in CNS - this means inefficient translation of the Sabin IRES and inefficient translation of Sabin IRES means poor yield of virus - this lower yield means limited spread within tissue - Sabin scenario in CNS - translation conpromised, lower yield, less spread - means immune system can clear the infection before the virus has killed too many neurons - KEY: BEFORE VIRUS HAS KILLED OFF TOO MANY NEURONS (lytic infection) - muscles In embryos by electroporating - measured amount of virus they got from wild- type from Sabin strain and ten hours afterewards, 100 times more virus for wildtype than Sabin strain - so difference in replication THESE TWO PAPERS together - the virus CAN replicate in CNS - but does so to lesser degree due to PTB (so IRES is important) but does not control - it's not the only thing that's important Ida-Hosonuma and Yoshikawa papers Why does the poliovirus not replicate else? Tissues other than CNS and intestines have interferon, which inhibit poliovirus replication Low level of interferon at all times in mo
More Less

Related notes for MGY440H1

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.