Very interesting, informative and worthwhile lecture. During the early 1970s, while I was in graduate school, kuru was referred to as kuru-kuru, the term used in Papua New Guinea. Anthropologists that have worked in PNG have insisted that the ritual cannibalism was done out of love and respect for the deceased. Kuru-kuru means terrible-terrible, with the doubling of the word emphasizing the word "terrible". During those days in the late 1960s and early 1970s, it was though to have an unidentified virus as its causative agent, sometimes referred to as a slow virus of the nervous system. The discovery of prions was a surprise, but on further reflection, it made good sense and seemed plausible and brilliant. In hindsight, one might think the prion concept of an infectious protein was almost obvious, but Nobel laureate Stanley Prusiner was a persistent trailblazer. Nobel laureate Daniel Gajdusek was also instrumental in early work on kuru, and by some accounts did classified pathogen work for the Army during the Korean War and at times thereafter. Mad Cow Disease caused some mild panic in Europe and elsewhere and, e.g., some governments were banning UK beef. During the 1970s, a friend's parents visited the UK, including Scotland, and some years later, the mother died of CJD. We were shocked, and it hit home in a very real way.
I'm UK resident who lived through the BSE scare and a regular blood donor. Unlike other countries (Ireland for example) the UK has precautions in place but no ban on donors from that time. There's an article in The Lancet regarding bans on blood donations for those resident in the UK at the time of the BSE outbreak and the evidence of the actual impact of vCJD: doi.org/10.1016/j.eclinm.2019.10.014
Interesting that you can knockout the prnp gene to make mice resistant to TSE's. Is there any potential for this knowledge to be used in gene therapy? Edit: I found a study: www.ncbi.nlm.nih.gov/pmc/articles/PMC2453229/ 1:02:37 - A 2020 study linked viewing this diagram to recurrent nightmares.
Outbreaks of violence follow epidemic patterns, is quite interesting and positive repurposing of infectious disease understanding, where people carry out "contact tracing" for victims of violence in areas with gang violence, and provide trauma counselling before a retaliation occurs
Great lecture, as with all the rest. I wanted to point out that at around 43:56 you credit Griffith (1967) with the original proposal that TSE agents were a protein. However, as mentioned in this commentary (www.nature.com/articles/509288b), Griffith's paper cites another 1967 paper by Pattison and Jones as the source of the idea, so the credit should probably go to them.
We (from southern Utah) just had a rare black mule deer die of chronic wasting disease. they are having it stuffed as a memorial, I hope they understand about CWD !!
Question: 1. RNA-pol-2 makes RNA from dsDNA. 2. A specific kind of viroid uses the host's RNA-pol-2 to make his RNA concatomers that are cut using the hammerhead ribozyme. I'm missing something, those two statements are contradictory. So what exactly is going on here? Does the host's RNA-pol-2 capable of using RNA to create RNA? (I guess not because it is called DNA dependent RNA polymerase) or is it that the host's dsDNA has integrated viroid genes in it? other? Thanks!
Yeah, I'm confused by this too. I thought only viruses encode the kind of RNA-dependent RNA polymerase that can do the replication described here... but a eukaryotic RNA pol 2 is replicating the viroid????
Did a bit of research, this paper goes a bit into the mechanism of how a DNA-dependent RNA polymerase could replicate a RNA genome science.sciencemag.org/content/368/6487/eaay0688?rss=1
The one on prions he said we should read? In English, it's Title: Madness and Memory Author: Stanley B. Prusiner ISBN (paperback): 0300216904 MARC: catalog.loc.gov/vwebv/staffView?searchId=40705&recPointer=0&recCount=25&searchType=0&bibId=17914378
Would it be fair to say that so-called "satellite viruses" (viruses that depend on symbiotic virus-virus interactions) and "virophages" (viruses that are parasitic in virus-virus interactions) are a partial continuation of the ecology lecture?
Question about prions. When one eats a protein it is usually broken nto its amino acids in the stomach and small intestine. If it survives it can not cross the membranes of the epithelial cells of the intestine. So the only way to get into the circulatory fluids is by somehow diffusing between cells something very improbable. So what it would be interesting to know is the probability of getting infected per gram of prion protein consume. Similarly for the contamination of hospital mentioned, after cleaning the remaining amount of prion would have been very small, and the the probability of ingesting it extremely small, so to me getting rid of the equipment was an exaggeration.
Very interesting, informative and worthwhile lecture. During the early 1970s, while I was in graduate school, kuru was referred to as kuru-kuru, the term used in Papua New Guinea. Anthropologists that have worked in PNG have insisted that the ritual cannibalism was done out of love and respect for the deceased. Kuru-kuru means terrible-terrible, with the doubling of the word emphasizing the word "terrible". During those days in the late 1960s and early 1970s, it was though to have an unidentified virus as its causative agent, sometimes referred to as a slow virus of the nervous system. The discovery of prions was a surprise, but on further reflection, it made good sense and seemed plausible and brilliant. In hindsight, one might think the prion concept of an infectious protein was almost obvious, but Nobel laureate Stanley Prusiner was a persistent trailblazer. Nobel laureate Daniel Gajdusek was also instrumental in early work on kuru, and by some accounts did classified pathogen work for the Army during the Korean War and at times thereafter. Mad Cow Disease caused some mild panic in Europe and elsewhere and, e.g., some governments were banning UK beef. During the 1970s, a friend's parents visited the UK, including Scotland, and some years later, the mother died of CJD. We were shocked, and it hit home in a very real way.
Oh noes, next one is the last episode ? But ... this is too interesting to end ! Looking forward to the next season :)
A personally extremely useful lecture, amongst numerous others !
Thanks for yet another great lecture Professor Racaniello
I'm UK resident who lived through the BSE scare and a regular blood donor. Unlike other countries (Ireland for example) the UK has precautions in place but no ban on donors from that time. There's an article in The Lancet regarding bans on blood donations for those resident in the UK at the time of the BSE outbreak and the evidence of the actual impact of vCJD: doi.org/10.1016/j.eclinm.2019.10.014
Excelente análisis gracias por compartir desde Santiago Miahuatlan Puebla México.
Interesting that you can knockout the prnp gene to make mice resistant to TSE's. Is there any potential for this knowledge to be used in gene therapy?
Edit: I found a study: www.ncbi.nlm.nih.gov/pmc/articles/PMC2453229/
1:02:37 - A 2020 study linked viewing this diagram to recurrent nightmares.
Thank you so much for doing these videos! Really appreciate it.
3:21 Since RNA can have enzymatic properties, does DNA too?
Most of the enzymatic activity is performed by the 2' OH group, which is not present in DNA. So, there is no example of catalytic DNA.
Yes, it is called DNAzyme. However, DNAzymes are selected in vitro, not naturally occurring.
Outbreaks of violence follow epidemic patterns, is quite interesting and positive repurposing of infectious disease understanding, where people carry out "contact tracing" for victims of violence in areas with gang violence, and provide trauma counselling before a retaliation occurs
Great lecture, as with all the rest. I wanted to point out that at around 43:56 you credit Griffith (1967) with the original proposal that TSE agents were a protein. However, as mentioned in this commentary (www.nature.com/articles/509288b), Griffith's paper cites another 1967 paper by Pattison and Jones as the source of the idea, so the credit should probably go to them.
Nice information
We (from southern Utah) just had a rare black mule deer die of chronic wasting disease. they are having it stuffed as a memorial, I hope they understand about CWD !!
Question: 1. RNA-pol-2 makes RNA from dsDNA. 2. A specific kind of viroid uses the host's RNA-pol-2 to make his RNA concatomers that are cut using the hammerhead ribozyme. I'm missing something, those two statements are contradictory. So what exactly is going on here? Does the host's RNA-pol-2 capable of using RNA to create RNA? (I guess not because it is called DNA dependent RNA polymerase) or is it that the host's dsDNA has integrated viroid genes in it? other? Thanks!
Yeah, I'm confused by this too. I thought only viruses encode the kind of RNA-dependent RNA polymerase that can do the replication described here... but a eukaryotic RNA pol 2 is replicating the viroid????
Did a bit of research, this paper goes a bit into the mechanism of how a DNA-dependent RNA polymerase could replicate a RNA genome science.sciencemag.org/content/368/6487/eaay0688?rss=1
Which book is recommended for this
The one on prions he said we should read? In English, it's
Title: Madness and Memory
Author: Stanley B. Prusiner
ISBN (paperback): 0300216904
MARC: catalog.loc.gov/vwebv/staffView?searchId=40705&recPointer=0&recCount=25&searchType=0&bibId=17914378
Would it be fair to say that so-called "satellite viruses" (viruses that depend on symbiotic virus-virus interactions) and "virophages" (viruses that are parasitic in virus-virus interactions) are a partial continuation of the ecology lecture?
excellent course, love it!
Very educating, thanks !
I recall lichens could break down prions-?
Great lecture
Thanka Dr Racaniollo for proving thaf knowledge is an ever dynamic process. Great Prof we need righf now dyring covid 19 pandemic
Question about prions.
When one eats a protein it is usually broken nto its amino acids in the stomach and small intestine. If it survives it can not cross the membranes of the epithelial cells of the intestine.
So the only way to get into the circulatory fluids is by somehow diffusing between cells something very improbable.
So what it would be interesting to know is the probability of getting infected per gram of prion protein consume.
Similarly for the contamination of hospital mentioned, after cleaning the remaining amount of prion would have been very small, and the the probability of ingesting it extremely small, so to me getting rid of the equipment was an exaggeration.
✋👁️👁️🤚
First! Hahaha