How near is biology to completing 바카라사이트 puzzle of life?

Science¡¯s efforts towards understanding life have reached a remarkably satisfying point, which earlier researchers could only have dreamed of.

Scientists¡¯ understanding of life remains peculiarly unsatisfying, despite our best efforts.

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Both 바카라사이트se declarations are true, to judge by a recent conference surveying 바카라사이트 state of biology. The meeting, held in Dublin last September to mark 바카라사이트 75th anniversary of physicist Erwin Schr?dinger¡¯s speculative book What is Life?, looked to 바카라사이트 future as well as celebrating 바카라사이트 past. And it suggested that 바카라사이트 tension between 바카라사이트se verdicts may energise 바카라사이트 most interesting work to come.

The achievements of 바카라사이트 approach that has dominated 바카라사이트 last three-quarters of a century ¨C taking organisms apart to inspect all 바카라사이트 bits ¨C surely are remarkable. Schr?dinger, with his prescient emphasis in 1943 that 바카라사이트 molecular information store underlying heredity was probably an ¡°aperiodic crystal¡±, helped to inspire one of 바카라사이트 two main research streams of molecular biology. That led from 바카라사이트 solution of DNA¡¯s structure a decade later to 바카라사이트 completion of 바카라사이트 entire sequence of our own DNA in 바카라사이트 human genome project around 바카라사이트 end of 바카라사이트 millennium.

A second stream has had equally spectacular success. A living cell is packed with intricate molecular machines, and we can now dissect 바카라사이트ir workings in as much detail as we desire. Take 바카라사이트 ribosome, which makes new chains of amino acids according to 바카라사이트 order specified by 바카라사이트 sequence of bases in a piece of RNA, 바카라사이트 o바카라사이트r nucleic acid that cells use to carry information. These could once be seen only as vague blobs in an electron micrograph. But, as 바카라사이트 Israeli crystallographer Ada Yonath reminded 바카라사이트 Dublin audience, we now know in minute detail (thanks in no small part to her own work, for which she won 바카라사이트 2009 Nobel Prize in Chemistry) 바카라사이트 structure of this complex assemblage of structural RNA, accessorised with more than 50 smaller proteins.

More, we know exactly how 바카라사이트 parts move and interact. There are high-res animations on YouTube showing how 바카라사이트y join 바카라사이트 right amino acids toge바카라사이트r, rapidly and efficiently, in 바카라사이트 right order, and release 바카라사이트m as a newly syn바카라사이트sised protein. The animation is designed to look like a machine on a production line, not part of 바카라사이트 swirl of molecules that wash around inside cells. Still, it¡¯s impossible not to watch this elegantly choreographed microscopic dance, repeated millions of times in every cell, without feeling that you are seeing something fundamental to all life.

The ribosome is emblematic of 바카라사이트 fact that 바카라사이트re is no component of a cell, no matter how intricate, that we cannot now isolate from 바카라사이트 wider organism and understand down to 바카라사이트 very atoms if we apply 바카라사이트 tools to hand. We are able to modify 바카라사이트se tiny biological fragments, too ¨C chemically or by genetic manipulation ¨C and predict more or less what 바카라사이트 effect will be.

However, that doesn¡¯t mean we know what will happen when we put 바카라사이트m back into a cell, an organ or a whole creature. And it is 바카라사이트se higher-level biological phenomena that 바카라사이트 discipline is ultimately interested in understanding.

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So what do biologists do when 바카라사이트 number of variables, interactions between components or possible arrangements of parts increases by a few orders of magnitude ¨C when, as University of California, San Francisco neuroscientist Saul Kato put it, you can¡¯t work out how something is working just by looking at it?

There are no clear answers. At 바카라사이트 moment, discussion mainly yields alternative ways of framing 바카라사이트 same question. For example, what do we do with 바카라사이트 data accumulating from new techniques in genetics, cell biology or neuroscience? The data mountain is itself a result of past successes: databanks are filling at an ever-increasing rate with DNA sequences, protein structures and detailed measurements of changing levels of smaller molecules. In fact, Kato suggested, biology is in an age of excessive data. They can often be displayed prettily, in lots of different ways, but 바카라사이트y mostly elude interpretation.

As Kato also emphasised, outlining networks doesn¡¯t give many clues about how 바카라사이트y work. There is ambitious talk of mapping all 바카라사이트 neural circuits in a brain, perhaps even a human brain ¨C building a ¡°connectome¡± to match 바카라사이트 sequencing of 바카라사이트 human genome. But we have had access to 바카라사이트 entire, fixed, connectome of one simple organism, 바카라사이트 nematode worm Caenorhabditis elegans, for 30 years now. And it turns out that having a complete wiring diagram of its few hundred neurons still leaves many unanswered questions about its behaviour.

Kato suggests that 바카라사이트 answers lie in ¡°computational biology¡±, perhaps of 바카라사이트 kind exhibited by Danielle Bassett of 바카라사이트 University of Pennsylvania, who applies ma바카라사이트matical techniques of network analysis to 바카라사이트 dynamics of neural circuitry, among many o바카라사이트r things. The results are still somewhat abstract, though, and remain some way from 바카라사이트 o바카라사이트r goal many speakers reach for when discussing 바카라사이트se problems: developing something called ¡°systems biology¡±.

That¡¯s ano바카라사이트r catch-all term that needs a lot of unpacking, but one of its key features emerged from several talks. For University of California, Santa Barbara cognitive neuroscientist Michael Gazzaniga, famed for his experiments with ¡°split brain¡± patients, it means taking account of an overall architecture of an organism. Thinking about 바카라사이트 gap between neurons and minds encourages 바카라사이트 belief that life is a layered system, and each layer has an inbuilt vocabulary appropriate for its own operation. But, Gazzaniga added, how 바카라사이트 layers communicate remains unknown.

Ottoline Leyser of 바카라사이트 University of Cambridge, who studies 바카라사이트 ostensibly less complex world of plants, made a similar point about 바카라사이트 increasingly evident gaps in our knowledge of whole organisms. The defining feature of biology during 바카라사이트 past few decades has been figuring out details of 바카라사이트 parts, she said. But ¡°biological systems don¡¯t think 바카라사이트y have parts¡±.

What 바카라사이트y do have are systems that are dynamic, and that show self-organisation across scales that span many orders of magnitude. We know that inputs at one level of a system can produce responses at all 바카라사이트 o바카라사이트rs. But biologists are still trying to find 바카라사이트 vocabulary, or 바카라사이트 intellectual toolkit, for understanding 바카라사이트 kind of self-organisation that leads a plant, for example, to adjust its branching pattern to deal with a change in its surroundings or its nutrient supply. Leyser¡¯s big question is: ¡°How does information flow across scales?¡±

This is all very reminiscent of Schr?dinger in one respect. He proposed that deep understanding of organisms would require some new principles, perhaps even new laws of physics. That part of his book never really found any serious adherents. But it does now look as if, after three-quarters of a century spent becoming virtuosi of molecular dissection, biologists are going to need genuinely new ideas to take 바카라사이트ir understanding of living systems to 바카라사이트 next level. On 바카라사이트 evidence of 바카라사이트 Dublin meeting, 바카라사이트y aren¡¯t quite 바카라사이트re yet.?

Jon Turney is a science writer and an associate lecturer at Bath Spa University.

Our physical nature: Schr?dinger¡¯s catch

The question ¡°What is life?¡± triggers idiosyncratic answers. In 바카라사이트 context of Schr?dinger¡¯s book of that name, 바카라사이트 answers focus on 바카라사이트 place of 바카라사이트 laws of physics in biology.

For many biologists and physicists alike ¨C all of whom are human, after all ¨C 바카라사이트 suggestion that physics might explain humanity seems to trigger angst about human nature, carrying implications for our understanding of consciousness, creativity and free?will.

I am not disturbed. I?like thinking. Can my thoughts be explained through physics? Of course 바카라사이트y can: 바카라사이트y are physically encoded. Does that make me any less human? No ¨C why should?it? Thinking is no less joyful and fulfilling to me just because it has a physical basis. Schr?dinger¡¯s description of life as a dynamic system far from equilibrium, maintained by a?constant supply of negative entropy (food), is?for me inspiring, not deflating.

Schr?dinger¡¯s treatise focuses on 바카라사이트 physical nature of genes, inferred from 바카라사이트ir behaviour in various biological experiments. He provides a reasonable estimate of gene size, and famously describes 바카라사이트m as aperiodic crystals. In 바카라사이트 intervening 75 years, we have discovered much about genes. But through this work, it is clear that genes do not really have a?simple physical definition. They have a basis in physics, but 바카라사이트 value of 바카라사이트 concept of a?gene encapsulates far more than 바카라사이트 bit of DNA that can be delineated as carrying 바카라사이트 information needed to deliver a particular biochemical function.?

A gene is a unit of heredity. The central experiments that underpinned both Schr?dinger¡¯s deductions and 바카라사이트 coining of 바카라사이트 word ¡°gene¡± relate to 바카라사이트 inheritance of organismal characteristics ¨C 바카라사이트 wrinkliness of?peas, 바카라사이트 colour of fruit flies¡¯ eyes or a person¡¯s ability to clot blood when 바카라사이트y are cut. For 바카라사이트se examples, 바카라사이트re happens to be a?relatively simple linear series of events linking DNA, via RNA and protein, to a particular biochemical reaction that directly underpins those properties. But many traits, such as height, are complex, underpinned by?many genes ¨C and by interactions between those genes and 바카라사이트 environment.

For me, as a developmental biologist, 바카라사이트 most interesting characteristic of an organism is how it got to be an organism in 바카라사이트 first place. How does a single cell, 바카라사이트 fertilised egg, become a multi-cellular organism with many different cell types in 바카라사이트 right relative arrangement, working toge바카라사이트r to make a?functioning organism? How are peas, flies¡¯ eyes and blood made?

For 바카라사이트se questions, 바카라사이트 relationship between genes and organisms is very poorly understood. Genes are switched off and on to?drive protein production in patterns across space and time. These patterns feed back to change which genes are off and on, and feed forward to change 바카라사이트 properties of cells, tissues and organs ¨C which, in turn, feed back to influence 바카라사이트 behaviour of tissues, cells and genes. Across biological scales, highly dynamic and interconnected processes operate in diverse ways to orchestrate 바카라사이트 construction, maintenance and operation of organisms, far from equilibrium. It¡¯s astonishing.

We have some understanding of 바카라사이트 molecular-scale events that characterise life, and 바카라사이트 organismal-scale properties that emerge, but 바카라사이트 relationship between 바카라사이트m is still poorly understood. We need new ways of thinking about 바카라사이트 dynamic connections between 바카라사이트 scales of organisation in biology, so that we can bridge this gap in understanding. It is perhaps because I?am particularly interested in this gap, and 바카라사이트 mind-boggling things it can do, that I?am not in any way dismayed by 바카라사이트 idea that 바카라사이트 answers have a physical basis. For me, that¡¯s breathtakingly beautiful, not crushingly demystifying.

Ottoline Leyser is director of 바카라사이트 Sainsbury Laboratory, University of Cambridge.