Karim writes:

Hi Rich , Nels and Vincent,

First of all, I love your show. I am a very faithful follower of Twievo and Twiv. Please Keep up the great work.

Just a little note, that comes out of my slight disappointment. You give all the credit in the IRES-Rack1 connection to a Sara Cherry genome-wide screen paper (PMC548945), in which RACK1 is not even mentioned in the main text. This paper identifies 66 ribosomal proteins (ribosome is roughly composed of 80 proteins) as important for IRES translation ! Please check PMC4243054 that formally proves that RACK1 is important for IRES translation. The reason of my ”childish” disappointment is that I am the first author on this paper and spent 5 years of my life working on it 🙂

No big deal or hard feelings tho! I know that all of us can miss stuff in the literature and are more likely to remember faces and talks we see at conferences.

Again, I love your show and will always be an ardent follower.

Thanks for all your efforts and work making my commute from SF to Stanford every day more pleasant !

Jeff writes:

Dear Nels and Vincent,

I greatly enjoyed the recent podcast on cnidarian-dinoflagellate symbiosis. I was struck by your speculation on possible evidence for cycles of cooperation and conflict between symbiotes based on diversification of proteins associated with mediation of the relationship. Do you know of any specific examples of such cycles of cooperation and conflict or references for investigations along these lines?

I am just getting into working on modelling of evolutionary dynamics, far from my background in experimental physics and TWiEVO is proving an enjoyable and accessible introduction to the field.

Best regards,


Dr Jeffrey Philippson

Simons Centre for the Study of Living Machines

National Centre for Biological Sciences (NCBS)

Bangalore, India

Daniel writes:

Hi Vincent and Nels,

I have a cool suggestion for a future TwiEVO episode.

Structure of histone-based chromatin in Archaea

Science  11 Aug 2017:

Vol. 357, Issue 6351, pp. 609-612

DOI: 10.1126/science.aaj1849

Work done by an amazing postdoc in a lab in my building, Francesca Mattiroli, working in Karolin Luger’s lab at the University of Colorado Boulder.



Adam writes:

Dear Nels and Vincent,

As usual, great discussion and conversation during the most recent episode!

Immediately after hearing about the RNA helicase DHX9, I thought of the 2013 PLOS Pathogens article from the lab of Grant McFadden titled “Myxoma Virus Protein M029 Is a Dual Function Immunomodulator that Inhibits PKR and Also Conscripts RHA/DHX9 to Promote Expanded Host Tropism and Viral Replication.”


In this work, the authors found that DHX9 interacts with the E3 ortholog of myxoma virus to promote virus replication under certain conditions. As Nels knows quite well, E3, encoded by the E3L gene [named from vaccinia virus], is a double-stranded RNA binding protein. It is enticing to hypothesize that E3 recruits DHX9 to viral dsRNA to help separate the strands and hence reduce immune stimulation. The authors did not directly study this in their work so I am only speculating.

I very much enjoyed hearing about another interesting role for DHX9!

Thanks for your wonderful podcast.

Matt writes:

Hey Nels and Vincent,

I had a quick comment on episode #23. In the episode you mention that ADAR enzymes deaminate guanosine to inosine. When in fact, adenosine deaminases like ADAR deaminate adenosine to inosine (like in the name). The inosine product does look like a guanosine to the translational machinery though, so you had all the pieces there. The A to “G” change is then what disrupts the perfect dsRNA duplex. Either way, it was a cool story!

Thanks again for all the great podcasts!



p.s. Nels, I won’t mention to Brenda that you switched it around 😉

Steve writes:

Hi Vincent and Nels,

I was pleased to hear of Vincent’s pick on the way Trump’s choices for heads of government agencies are all acting to deregulate the things those agencies were created control for the sake of people and planet.

As it happens, I have just written a note with an idea about what could be done to prevent this in future–if there was an all out campaigning effort:

There needs to be an expansion of the ‘clear and present danger’ concept in US rights law. This concept has been used as a way to limit the right of free speech in circumstances where such speech could have disastrous consequences. We need to extend this concept to *require* speech under the same condition:

The ‘Environment Protection Agency’ should not be able to prevent its scientists from informing the public about serious consequences of climate change; AND the EPA (and any other relevant agency) should have *a DUTY* to inform the public of anything which presents a clear and present danger, as determined by reputable scientists.

The concept should also be extended to businesses like fossil fuel cos, tobacco cos, chemicals and pesticides cos, and drug cos.

With this new constitutional concept in place, situations such as you described, and more below, would immediately be challenged in court.

“An agency spokesman declined to offer an explanation for the cancellation of the October 23 climate-change talks in Rhode Island, where three scientists were scheduled to discuss the effects of climate change on Narragansett Bay, the region’s largest estuary. According to the Times, the scientists were set to present findings that climate change is impacting sea level, precipitation, air and water temperatures, and fish near the estuary. Now, the scientists are reportedly allowed to attend the event, but they’re barred from making any presentations and from going to the opening news conference, exacerbating fears that Pruitt’s agency will silence employees from speaking out on—or even continuing to study—the widely proven phenomenon.

Though it’s unclear whether the two events are connected, the cancellation came just a day after a Times report that a recently appointed executive at the agency might be responsible for weakening regulations. Nancy Beck, who joined the E.P.A.’s toxic chemicals unit in May, spent the previous five years at the chemical industry’s trade association, the American Chemistry Council, as an executive. During her tenure, the agency has re-written rules allowing the use of some toxins and making health effects of others more difficult to track, including perfluorooctanoic acid, or PFOA, an ingredient used in non-stick pans that has been said to cause birth defects and kidney cancer. The changes made under Beck’s leadership could result in an “underestimation of the potential risks to human health and the environment,” according to a confidential internal memo from the top official at the Office of Water, the Times reports, while E.P.A. spokeswoman Liz Bowman (a former American Chemistry Council spokeswoman) sharply disputed this account. “No matter how much information we give you, you would never write a fair piece,” she said. “The only thing inappropriate and biased is your continued fixation on writing elitist clickbait trying to attack qualified professionals committed to serving their country.”


All the best,

Steve Hawkins

In Luton UK,

(Where it is a beautiful blue and gold, Autumnal sunset evening, on the day the clocks went back to GMT to give us more morning light and less evening :/ .)

John writes:

Hi Vincent and Nels,

I know that someone on the TWiX teams picked a previous Acapella Science song (about Crispr-Cas9) as a pick-o-the-week.

This one is new and I figure it might fit on TWiEvo:

Evo-Devo (Despacito Biology Parody)



Thanks and Regards,

John in Limerick.

Melanie writes:

Dear Drs Elde and Racaniello,

I want to thank you for your dedication to this podcast. As a scientist surrounded by non-scientists, it is often the only thing that makes me feel not so lonely. I’m a biologist working for the federal government and sometimes I feel like an iceberg in the Caribbean – out of place and slowly breaking up. The TWIX podcasts really help. Keep it up.

I’d like to suggest a pick of the week. Most of what you guys talk about is on the gene or molecular level. How about looking at evolution through comparative anatomy? What’s in John’s Freezer is an informative and fun site for anyone interested in studying evolution on the macro level.

Keeping this short so you can get back to podcasting.