William Rtklif (Ratcliff) University of Minnesota was sitting one day in the office of his supervisor, Michael Trevisan (Travisano), and they wondered what experiment can edit that will shed light on one of the big questions of life sciences. "We ansel elgort decided origin of life (transition from mineral first life form) is too complicated," said Rtklif Carl Zimmer (Zimmer), author and science correspondent of The New York Times, "" Then we thought - except for origin of life, what would be the coolest ansel elgort ? " The coolest, the opinion of Rtklif and Trevisan, will explore the origin of multicellular animals - how single-cell organisms began to cooperate, forming arrays ansel elgort multicellular complex, which eventually led to animals ansel elgort and plants, where billions of cells play many different roles in the body one. In contrast ansel elgort to the origin of life, most researchers believe that happened once (or at least, only one life form has survived and led all existing organisms), transition multicellular forms occurred several times in different dynasties. Rtklif and his colleagues decided to encourage the creation of multicellular bodies one-celled creature - fungus yeast Saccharomyces cerevisiae.
The researchers grew single-cell yeast, genetically identical, in 15 different containers. Every day, some cells were transferred into a new container, where they will continue to grow. But these cells are not random - they collected the yeast that sank to the bottom ansel elgort after a slight rotation of the centrifuge container (centrifuge). Because multicellular bodies may be greater of single and are more likely ansel elgort to sink, they will have a better chance to gather and pass whatever. In this method the researchers have created a selection pressure on yeast cells: an environment that rewards the creation of multicellular bodies.
The results were immediate. After 60 days, all 15 tanks were multicellular bodies, researchers ansel elgort called "snowflakes" because of the shape. Bodies have been created by an entire division of yeast cells. These yeast in their original state divided by "budding", that is, cell-formed ansel elgort subsidiary of the parent cell and then breaks up with him. The new varieties ansel elgort daughter cells do not completely cut off from the parent, but stayed close to him. This created multicellular bodies, composed of cells that are identical to each other genetically. Matching yeast multicellular life did not end with the formation of these bodies. Yeast developed what researchers described a simplified version of the division of labor within the body - when the "snowflake" reaches a certain size, it broke in two, and some cells have to die to make this possible. These cells kill themselves, a process called apoptosis, to enable the growth and reproduction of the whole body. The researchers believe such processes might occur when single-cell organisms became multicellular first time, hundreds ansel elgort of millions of years ago. The ease with which developed multicellular bodies ansel elgort in this study may indicate that this feature is quite easy to develop the appropriate environment.
The researchers published their findings in the journal PNAS. But this was not the end of it. In fact, the publication of the study is never the end of it - at least not when it comes to studies of successful and interesting. Good research should stimulate debate in the scientific community, and scientific magazines are full responses to previous studies. But times change, and the scientific discussion moves too slowly to other provinces; Various social networks and the Internet in general - are beginning ansel elgort to play a role in this area. Social Science
The first reactions were - how not - via Twitter. Due to Zimmer's article ansel elgort in New York Times, sang some researchers, including Leonid ansel elgort Krogylk (Kruglyak) from Princeton University and Michael Eisen (Eisen) from UC Berkeley, the Hstiigotihm article. Yeast, commented, are multicellular origin - and perhaps experiment they just reverted back to an earlier (we note that the article of Rtklif treated for that matter). ansel elgort They also wondered why the researchers did not Rtzfo the genome of the new varieties to check exactly these mutations led to the new situation. Zimmer answered them as best he could, and then transferred the call to Rtklif, and it gave him a detailed answer, he says, even if some strains of yeast indeed create multicellular bodies, enter where they used is not. Developed multi-celled experiment is not a return to an earlier, but the result of a mutation disrupted the separation of the daughter cell from the mother.
Zimmer published the critical tweets and answer Rtklif scientific-popular blog his The Loom. Then the second stage. A reader of the blog detailing his opinion and certain aspects reservations ansel elgort post a comment article, and Rtklif himself responded and answered at length on all the points raised. An interesting discussion evolved from a few readers and Rtklif, when Trvsino - offering of Rtklif - also joined at one point.
We think the answer is yes. Of course, this depends to a large extent the debate is transacted at the hostel, and most of all - it depends on the participants. Zimmer's blog responders were well versed in the subject, treated with respect for each other, and clearly joined out of curiosity and desire to learn. Needless to say, this is not necessarily the case in all the discussions taking place online. On the other hand, these discussions allow the public does not read scientific magazines exposed disagreements among scientists, and the aspect of scientific work that is not usually the general public. Rtklif admirable that he was willing to spend time and meet readers on Twitter and blog Zimmer. We hope that more and more scientists understand the importance of exposing their research to the public, and not be afraid to enter discussions with readers - specialists and non-specialists - different arenas, instead of staying in the confined area of the scientific magazine.
Ratcliff, WC et al. Experimental evolution of multicellularity. PNAS 109, 1595-1600 (2012). doi: 10.1073 / pnas.1115323109 to receive notice of the publication of new records Subscribe to blog at the top right, under the heading "Register for Updates" or follow on Twitter: FollowScPhile
Previous post
RSS - Posts
DNA
No comments:
Post a Comment