Well, I’ve never been one to follow the trend, so I decided to write about the ACS after it was actually over. Forget this real-time blogging stuff! (and if you’re only reading this blog for the ACS content, keep reading for the next few days).

I wanted to offer my congratulations to Drs. Puglisi and Williamson for putting together a great series on the Biophysics of RNA. I went to 2 different sessions (both were outstanding), and the remaining sessions were always high on the list of the 5 concurrent sessions I wanted to go to. On Tuesday afternoon, I caught Dan Herschlag’s talk, who “wants to set forth principles and physical organic parameters to make RNA folding less mysterious.” And indeed, his talk was a great tour through different forces and conditions that need to be considered in elucidating RNA folding. He was also very gracious when I went up after the talk and asked, basically, “can you explain your whole field to me during the coffee break?” In fact, he and the other speakers I cornered got me pretty interested in the topic, so if I ever leave my current job you may find me back at the bench in an RNA lab.

Aside from just being nice people in general, the RNA crowd made a nice counterpoint to the person who found my phone and promptly downloaded nearly $300 worth of games (and as you can imagine, it wasn’t in an attempt to spruce it up for me before giving it back…). I guess I’m learning to appreciate all those silly contraptions people have for keeping their phone nearby, as my track record with phones and the ACS isn’t so great…

Well, here’s hoping the next ACS organizers keep up the good work, or at least that I stop losing things…

Catherine (associate editor, Nature Chemical Biology)

“Germline transmission”: how many time have mouse geneticists prayed to the Gods to decipher this magical message from their Southern blots and PCRs when trying to generate a knockout line?

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Indeed, injection of genetically altered ES cells into blastocytes gives rise to mice which are only partially derived from the engineered ES cells. Unfortunately, contribution of ES cells to the germline cannot not be controlled, and, as a result, only a fraction of the chimeras actually transmits the mutation to their offspring. “Gemline transmission” represents thus one of the major bottlenecks in the generation of a comprehensive library of mouse mutants with targeted deletion in every gene of the genome.

Hopefully the recent technology (the “VelociMouse method”) developed by Regeneron Pharmaceuticals will definitively overcome this hurdle (Poueymirou et al, 2007): by disrupting the zona pellucida with help of a laser, ES cells could be injected into 8-cell stage embryos, resulting in F0 generation founder mice entirely derived from the ES cells, thus directly amenable to phenotypic analysis and breeding.

Together with the large-scale gene targeting in ES cells (Valenzuela et al, 2003, Auwerx et al, 2004, Austin et al, 2004,Grimm, 2006), this technological advance may well represent a major step towards a high-throughput functional genomics of a mammalian species.