The Lure of the Obscure? Guest Post by Frank Stahl

Image from Hochwagen Lab

This proposal was shouted out as “…one of the most important papers on the control of meiotic crossing over…” (Hawley 2006). Since then, “homeostasis” has been offered as the explanation for a variety of observations that demonstrate a degree of independence of crossover frequency (and sometimes crossover interference) from the frequency of double-strand breaks. As in the original yeast work, none of these papers questions whether “homeostasis” has anything to recommend it as an explanation because none has addressed the mundane possibility that crossover constancy reflects merely the normal operation of the system, rather than a reaction to a perceived aberration. 

Without trying to explore the universe of alternate explanations for “homeostasis” in this Blog, we offer just one simple one, based on the view that the crossover/noncrossover “decision” is made “early”, either before or at the onset of the period of double-strand-breaks (Storlazzi et al. 1996): In this none-too-original model, the first double-strand break to occur on a chromosome is immediately assigned to the pathway that leads to crossing over, accounting for both the “obligate crossover” (Jones and Franklin 2006) and the preservation of crossing over. Additional double-strand-breaks are directed to become crossovers when they meet the conditions imposed by crossover interference. [It appears notable that Drosophila, which clearly lacks an “obligate crossover”, has also shown no evidence of “homeostasis” (Stahl 2008).]

This blogger would like to be informed of any “homeostasis” data for which such a nonhomeostatic explanation fails.

  

LITERATURE  CITED

Chen, S. Y., T. Tsubouchi, B. Rockmill, J. S. Sandler, D. R. Richards et al., 2008  Global analysis of the meiotic crossover landscape. Dev. Cell 15: 401–415.

Hawley, R. S., 2006  "This is one of the most important papers on the control of meiotic crossing over..." Evaluation of: [Martini  et al., 2006  Crossover homeostasis in yeast meiosis. Cell 126: 285-295; doi: 10.1016/j.cell.2006.05.044]. Faculty of 1000, 14 Aug 2006. F1000.com/1033723#eval387934

Henderson, K. A., and S. Keeney, 2004  Tying synaptonemal complex initiation to the formation and programmed repair of DNA double-strand breaks. Proc. Natl. Acad. Sci. USA 101: 4519–4524.

Jones, G. H., and F. C. Franklin, 2006 Meiotic crossing-over: obligation and interference. Cell 126: 246–248.

Martini, E., R. L. Diaz, N. Hunter and S. Keeney, 2006  Crossover homeostasis in yeast meiosis. Cell 126: 285-295.

Martini, E., V. Borde, M. Legendre, S. Audic, B. Regnault et al., 2011  Genome-wide analysis of heteroduplex DNA in mismatch repair-deficient yeast cells reveals novel properties of meiotic recombination pathways. PLoS Genet. 7: e1002305.

Mehrotra, S. and K. S. McKim, 2006  Temporal analysis of meiotic DNA double-strand break formation and repair in Drosophila females. PLoS Genetics 2: 1883-1897.

Stahl, F. W., 2008  Countdown with Mehrotra and McKim. Online comment on Mehrotra and McKim (2006) 2(11): e200 doi:10.1371/journal.pgen.0020200.

Storlazzi, A., L. Xu, A. Schwacha and N. Kleckner, 1996 Synaptonemal complex (SC) component Zip1 plays a role in meiotic recombination independent of SC polymerization along the chromosomes. Proc. Natl. Acad. Sci. USA 93: 9043–9048.

Franklin W. Stahl
Molecular Biology
1229 Univ. of Oregon
Eugene, OR  97403-1229

My blog is back from the dead (sort of)

Greetings from New London, New Hampshire, where I am attending the Meiosis Gordon Research Conference this week. As such, it seems timely and appropriate to host a guest post on my (very dusty!) blog from Frank Stahl (pictured left). Frank contacted me recently to guest-post a short piece he wrote on crossover homeostasis. Enjoy!

People, Content & Technology @ ScienceOnline2010

I am a very frequent attendee and eager participant at scientific conferences: I have logged ~100 in my ~20 years in science. To me, meetings are easily one of the top five things that make being a scientist so much fun. Exchanging ideas (new & old), meeting people (new & old friends), showing off your work (usually new, but sometimes, old), having a good time (which never gets old!)....these reasons are all part of the experience. But sometimes meetings just get you fired up about something(s) and you leave with a fire lit under you. This was one of those for me. And although I knew that I would enjoy myself at Science Online 2010 (aka #scio10) and meet at least some of the criteria above, I was not prepared to leave with my rear side roasting with so many ideas and so much inspiration.

The jazz I got from #scio10 comes from three intertwined categories:

People. Meeting and interacting with people is my favorite conference activity. It's especially great when I first meet someone in person whose work I have followed. This is true for science meetings, but it worked on a wholly different scale for me at #scio10: of the 200+ attendees, I had previously met no more than 10 in person. However, I knew at least 50 more from their online work—mostly science bloggers. Come to think of it, that's probably alot like what happens at a graduate student's first scientific meeting, and I am reveling in that re-found sense of discovering a community that fits. And then there are the people that I met for the first time who I knew nothing about in advance. There are always new people to meet, especially when attending conferences for the first time. But I was stunned by the fraction of people I met who fell in the category of "why did I not know you before?". I can just hope that some of those folks had the same reaction to meeting me!

The intersection of people and content was probably the most amazing thing about this meeting. I have never seen such a meritocracy. Sure, science is based on merit, but there is a real ladder to climb and sometimes a glass ceiling to break. The participants at this meeting ranged from a 9th-grader who writes science computer games to internationally known science journalists (and a HUGE range in between). Many (probably most) of the presenters were self-made experts in newly emerging areas, some in the process of earning PhDs etc., and some that don't need to play in the academic world. Even in the currently-difficult times for both science and journalism (and many other things), there was a clear sense of "Yes we can!" that permeated #scio10 .

Content. The meeting couldn't have started out on a more content-relevant note for me: the first session I attended was "From Blog to Book: Using Blogs and Social Networks to Develop Your Professional Writing"As I am now digging into my sabbatical book project, this session jolted me to attention. The advice of Tom Levenson, Brian Switek and Rebecca Skloot was just what I needed. I must decide very soon whether to pursue the academic publisher route or to try the trade route taken by authors of most successful popular science books. Next on my schedule was "Rebooting Science Journalism in the Age of the Web" in which a panel discussed the sometimes uneasy ecosystem of blogs and more traditional media outlets. The somewhat controversial press-release site, Futurity, created some heat (and maybe some light), but the memorable lesson by Carl Zimmer about his reporting on the twisted biology of duck penises generated the most virulent meme of the whole meeting. In the third morning slot I joined the "Scientific Visualization" session in which Tara Richardson (@science_goddess) regaled us with the latest cool tools and facilitated some interesting discussion on this under-appreciated (and thus, under-developed) aspect of science communication.

On Saturday afternoon, I attended the helpful session "Scientists! What can your librarian do for you?"which reminded me that I can almost certainly make use of those smart people whose mission is to help me do my science (and writing) better. Next was "Open Access Publishing and Freeing the Scientific Literature (or Why Freedom is about more than just not paying for things)" moderated by friend and colleague Jonathan Eisen (aka @phylogenomics; pictured above). It's going to be a tough road to OA publishing, but I am starting to see that it is a fight worth waging. For the final session of the day, I joined the packed-to-the-gills session "Writing for more than glory: Proposals and Pitches that Pay" moderated by Rebecca Skloot with key insight from Ivan Oransky and Clifton Wiens. Although much of the session was aimed at pitching stories to magazines, there was a fair bit of discussion of book proposals and how to craft a project that publishers will buy—literally. Much to my chagrin, the first lesson was that the pitch "My book is on X" doesn't fly. Stories sell books and topics don't. OK, more homework for me...it might be a good thing that my book is "on Sex", but that isn't enough. So when the participants were invited to give their pitch to the experts, I knew that I wasn't up to snuff. However, shark researcher (and future author) David Shiffman (@whysharksmatter) bravely jumped right in—to our benefit. The most memorable line from the pitch-dissection was 'NPR is more important than PhD'; since David had been interviewed on NPR. Indeed, as I later found out to my surprise, David doesn't have his PhD (yet).

After a great banquet and party on Saturday night, I was ready to go again on Sunday morning, starting with "Broader Impact Done Right" hosted by a panel of postdocs, grad students and science communicators. The opening film, in which various portrayals of scientists in movies and television made us both laugh and cringe, presaged some great discussion about how we can appeal to various constituencies that we really need to reach. Since I wanted to hear more about science journalism, I next attended "Getting the Science Right: The importance of fact checking mainstream science publications — an under appreciated and essential art — and the role scientists can and should (but often don’t) play in it" I was surprised to learn about how unevenly the fact-checking is done, and when it is done, how arduous and expensive it can be! In the category of saving-the-best-for-last, the final session that I attended was "Blogging the Future – The Use of Online Media in the Next Generation of Scientists" in which a group of high school students from Stacy Baker's Biology Class individually presented their projects, ranging from an analysis of student use of blogging and the social web for education and fun to iPhone application development for science learning. These kids absolutely stole the show with their poise and content, giving many of us renewed confidence for science and its communication in the future.

Technology. As if the people and content weren't enough, in these three short days I also experienced some serious surges in my use of and appreciation for technology. For the first time ever, I didn't bring a pen or pad of paper to the meeting. I took all of my notes on my iPhone, which was the only device I used while onsite. In my office is a two-foot pile of legal pads and notebooks containing mostly illegible notes from 20 years of previous meetings. But in my difficult transition from paper to electrons (I am a very slow keyboard typist), I have gotten lazy about note-taking over the past years. So I was glad to find out for myself that I am a reasonably adept two-thumb note taker! And I can email myself my notes with one click!

I also jumped in with both feet to Twitter. As an occasional tweeter (@johnlogsdon), I use the medium for some things, but I had not yet figured out the ratio of function:fun. By using the hashtag #scio10 all of the meeting tweets were instantly readable by all of the twitter-ers (onsite & off) in REAL TIME. By the end of Day 1, I was hooked. As of writing, my total (13-month) tweet count is 235—of which ~70 were sent during the three days #scio10 (which currently total >6300)! Granted, some of those tweets were part of the fun game played at Saturday's banquet, in which the fastest tweet with the right answer won a prize. I apparently have mastered speed-tweeting, since I won one of the prizes: a signed copy of Rebecca Skloot's forthcoming book "The Immortal Life of Henrietta Lacks" (see image above).

There's so much more that I didn't say here, but I hope that my account will give you a sense of how pleased I am to have participated in #sci010. Thanks to Bora Zivkovic (pictured above), Anton Zuiker and everyone else (including the generous sponsors) who contributed to ScienceOnline 2010!

SMBE 2009 - Call for Symposia

Earlier this week, I posted a formal announcement on EvolDir that the organizers of SMBE 2009 are now accepting proposals for contributed scientific symposia. The proposals are due on January 12, 2009. See the meeting webpage (http://smbe2009.org) for more details.

I hope to get back to blogging soon!

Coitus Interruptus in Iowa

May 31 to June 3, 2009!

These are the dates for Evolution of Sex & Recombination: In Theory & In Practice.

Based on overwhelmingly positive responses from the previously scheduled speakers and registrants, we have decided to reschedule the meeting for next year. We are hopeful to have significantly drier weather in 2009.

The reborn Sex & Recombination meeting will immediately precede SMBE 2009, the annual meeting of the Society for Molecular Biology & Evolution that will also be held in Iowa City June 3-7, 2009. Both events are being hosted by the Roy J. Carver Center for Comparative Genomics with financial support coming from a number of sponsors.

I'll be posting here and on EvolDir as futher details become available.

Image shows the Iowa River as it runs through the University of Iowa on June 18th. Thanks to Monica.

Future Sex in Iowa??

Things have settled down a bit here in Iowa City. Although a significant portion of the campus has been hit hard by the flooding, my Department, lab and home have all been spared. We are "suspending non-essential activities" on campus this week, which means that my Department and lab are shut down for the rest of the week. Thanks to everyone for their concerns and kind wishes in this difficult time.

The organizing committee has not been able to meet to discuss the possibility of re-scheduling the Sex & Recombination meeting for a future date. I'll be querying the registrants in the coming weeks for their thoughts. I am also strongly considering attending the Evolution 2008 meeting in Minneapolis next week (as I had originally planned). If so, I'll be looking forward to hearing peoples' thoughts on this matter in person.

Again, thanks to everyone for their patience in this difficult time.

No Sex in Iowa

Contrary to yesterday's post, the Sex & Recombination meeting has now been cancelled. The flooding is bad and is getting worse in Iowa City. This turn of events is very disappointing, but necessary. 

(Wet) Sex in Iowa

For those of you who might be wondering, the Evolution of Sex & Recombination meeting is continuing as scheduled (Monday 16 June to Thursday 19 June). Although parts of Iowa City are being hit rather hard with floods, the meeting venue and most of the accommodations are still in good shape. Updates will soon be available on the meeting website.

Photo by atoomsen.

Sex in Iowa

I'm sorry that I have been such an infrequent blogger for the past few months, but life has been busier than normal.

One of the things keeping me away is that I have been organizing a meeting, "Evolution of Sex & Recombination: In Theory & In Practice" to be held in Iowa City June 16-19.


We now have a final speaker schedule together and it looks to be a very exciting meeting! Registration is still open for poster-presenters and attendees.