TWiV 265 letters
Dear TWIV Illuminati,
The good Prof Spindler was correct about the pronunciation of my name; it is pronounced, “johnny”. Thank you.
I did not know Julia Child personally, only tangentially: Once I was seated next to her at a beauty salon in Harvard Square. And, one of my partners still takes care of the grandchildren of the butcher she used in Cambridge. That’s as close as I ever got to meeting her.
Enjoy rest and renewal over the holidays! Best to you et al.
Your Cambridge pediatrician friend,
Johnye Ballenger, M. D., FAAP
West Cambridge Pediatric and Adolescent Medicine
Hi Vincent and Dickson,
I am completely up to date on all your podcasts, so have gone back and started TWIV from the beginning.
I am up to TWIV #60 which is a Virology 101 and a couple of things are not quite clear to me on flu replication. If you could answer these couple of queries it would be much appreciated.
1. Does each minus stand have its own polymerase attached, or does one polymerase have to make mRNA’s from each stand?
2. The enzyme that creates the full length copy of the genome, does it make a full length plus strand as a jig first? Is that enzyme in the virion, or is it made by one of the mRNAs?
Shane from Australia
Hello TWiV creators and collaborators,
Since the holiday season is coming up again, I thought I would ask you a question about clementines and other mandarin oranges. I don’t know how it is for the rest of the world but during the holiday season in the Scandinavian and Baltic countries, clementines are at the peak of their popularity. Because gastroenteritis has also an increase around that time many healthcare workers have started advising people to wash their clementines before putting them on the table in fear that the norovirus can be spread through contact with the peels. Many people don’t wash them as the peel is not eaten but there is still a risk of cross contaminating the edible part.
I do agree that all fruits should be washed before serving however I have not found a lot of information on the norovirus and clementines. Is this a common path of infection and the concern is relevant or is gastroenteritis more common around the holiday season as people are more inside and together in groups? Is this a common problem around the world?
I write to you from Västerås, in Sweden. The weather is still far from the white christmas many people are waiting for but it is getting colder with temperature commonly being under 0C.
All the best for you and keep up the good work,
School of Business, Society & Engineering
Nick Acheson writes:
I listened to and watched your recent TWIV from Tegernsee , very well done and interesting. You have become a real communications professional and are serving an important role, not only for the general public but also for virologists!
During that discussion you touched on the question of the origin of viruses, which Claverie et al. believe may be by capture of cellular organisms as parasites in a cell, then loss of function. This makes much sense to me for the very large viruses (will there be even larger ones than the 2.5 Mbase pandoraviruses?). However, there is no reason to believe that all viruses have a unique origin, as you alluded to in discussing RNA viruses. Viruses could even be originating in the present world, why not?
At any rate, I think there are good reasons to believe that viroids, retroviruses, ss RNA viruses, ds RNA viruses, small DNA viruses, and large DNA viruses may have each had distinct origins. I outlined some of these reasons briefly in the second edition of my textbook, Fundamentals of Molecular Virology, and enclose a pdf file of chapter 3, The World of Viruses, which ends with the discussion of the possible origin of viruses (pp 40-44).
You may have had TWIV sessions devoted to this topic, as I have not been able to follow all your prolific TWIV productions, but if not, it might be interesting to plan such a session in the near future.
For your information, another chapter in the second edition of my textbook covers very large DNA viruses, specifically viruses of algae and Mimivirus (this predated pandoraviruses).
By the way, I have fond memories of southern Bavaria, where Tegernsee is located, as I spent a summer in Achenmuhle, near Rosenheim, during my second year as a graduate student at Rockefeller University, learning German at a Goethe Institut school there. I stayed in a farmhouse with local Bavarian farmers just up the hill from the small town of Achenmuhle. I didn’t make it to Tegernsee, but visited Chiemsee, a bit further east; Munich, Salzburg, and finally Vienna, and spent some gemutlich times in an Austrian bar (forget the name) in Kufstein, just across the border from Germany. A beautiful region with lots of history (some of it not good, as concentration camps were also located nearby, and Hitler had a favorite castle there also).
Dr. Nicholas H. Acheson
Department of Microbiology and Immunology
A few episodes ago Vincent mentioned that ASM has public lectures every so often. I live in DC so I was excited to hear this — though sorry to have missed the microbiology of beer lecture, as that has long been a pet topic. However I’ve been unable to find a schedule for these public events on the ASM website or on the MicrobeWorld page I get as a redirect. I’m probably missing something obvious, but would you mind pointing me to a calendar or similar?
If you have time for a question, as well, I’ve been muddling over something and would love to hear your takes. During a discussion of HIV restriction factors, someone posited that lentiviruses have been a major driver of primate evolution, at least recently (whatever recently means in the context of evolution). I haven’t been too successful thinking of evidence for this — I’m sure due to my ignorance, rather than a lack of support — but it popped into my head again while listening to your recent discussion of HERVs in the MMTV episode. So if I may: what do you think of the idea that lentiviruses have driven primate evolution; and what evidence do we have already, and what other evidence would you _expect_ to find if you were to look into this further?
All the best this holiday season, and thanks for your help,
My name is Lindsey, I am a student at University of Maryland, Baltimore County and an avid listener of your Virology netcast. I have a question pertaining to the brief conversation you and Rich had on MicroRNA’s during episode 238, “Lost in Translation”. As you stated, MicroRNAs bind to 3′ untranslated regions and have been found to affect the post-transcriptional stability of the mRNA. In other words, just like transcription factors (TFs), microRNA’s are master regulators of the cellular system. So my question is should we expect to see “Promoter-like” sequences (similar to what we see for TF’s) for microRNA’s within the 3′ untranslated regions and if not, then what is it about microRNA that allows them to regulate gene expression the way they do? Thank you so much for your time, I look forward to hearing your response.
You might like to know about this.
You guys should probably know about these do-it-yourself bio laboratories springing up across the country.
> Definition of “viri” (www.urbandictionary.com/define.php?term=viri)
> The product of a socially deprived 14-38 year old individual with way too much computer time and no job.
Dr. Howard (Howie) Weiss
Professor of Mathematics
Georgia Institute of Technology
In case you have not seen this – maybe you can dig out the recording of past discussions about Jenny McCarthy and replace her name with Katie Couric. Unfortunately Couric probably has a wider audience.
[Couric has since offered a totally inadequate apology: http://www.slate.com/blogs/bad_astronomy/2013/12/12/gardasil_and_katie_couric_talk_show_host_apologizes_but_the_damage_is_done.html]
Neil followed up:
Sorry if you’ve discussed this already – I’m way behind on my TWIV episodes!
This is a mild improvement. Too bad she can’t go back and make the millions of viewers unsee the original episode…
Dear TWiV gang:
I’d like to submit a listener pick of the week (hopefully no one has beaten me to it), and I think this could possibly be a contender for an IgNobel, especially when the person I received it from started the email with “It’s not fake and it’s not The Onion…”. But with a title like “Moderate alcohol consumption enhances vaccine-induced responses in rhesus macaques.” (http://www.ncbi.nlm.nih.gov/pubmed/24200973) I still did a double take. It’s the perfect excuse to have one more drink at the holiday party, for your immune system of course.
I’ve also heard lamentations over the lack of access to some of the papers discussed on TWiV, especially for those not affiliated with a university. There is one route I haven’t yet heard mentioned. Large city libraries often subscribe to services like Academic OneFile and have access to a number of scientific publications, though some like Science and Nature have a one year embargo. Even if you aren’t a resident of the city itself you can still get a library card, I lived in the suburbs of San Francisco and Seattle and both libraries allow residents of the larger metropolitan area to get a card. Best of all, once you have a card, you use it to access article databases from home. I only found out about this in the last year, and I hope this helps some of my fellow listeners who are interested in reading the papers you discuss.
And as per tradition, I’d like to report that it’s 32°F (0°C) and cloudy here in the Puget Sound area. We’re expecting a storm tonight and into the morning with forecasts of freezing rain, warm wet snow or some combination of the two depending on who you ask. My morning commute should be very interesting.
Wishing everyone happy holidays,
Check out this video on YouTube:
Johnye Ballenger, M. D., FAAP