Scientists noticed, the yeast hybrids adapted Darwin

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Hybrid creatures Darwin was fascinated by his life. The fact that related species are able to create offspring together, have the characteristics of both, but usually are unable to reproduce and pass these traits third generation was further proof theory eyes species diverge gradually.
Hybrid creatures Darwin was fascinated by his life. The fact that related species are able to create offspring together, have the characteristics of both, but usually are unable to reproduce and pass these traits third generation was further proof theory eyes species diverge gradually. Now, 200 years after the birth of Darwin, vivek consulting group Weizmann Institute of Science considering using hybrid organisms, which cause one species to be different vivek consulting group from the other and what happens in human hybrids.
Darwin never heard of genes when offered the theory of evolution in his book "Origin of Species". Now, after deciphering the genetic code, it turns out that genetic mutations are responsible for only some of the differences between the sexes. Most of the differences stem from the way in which these genes are expressed vivek consulting group - "called" - to create the proteins they encode. How these differences emerging in evolution? Prof. Naama Barkai, Department of Molecular Genetics, Professor Avi Levy Department vivek consulting group of Plant Sciences, and graduate students Itay Tirosh and Sharon his vehicle, they found that one way to explore the differences vivek consulting group between the two species of yeast is to unite their genetic material together and create a Mr. Hybrid, vivek consulting group that is a hybrid. Findings of the study were recently published in the journal vivek consulting group Science.
Like human cells, yeast cells hybrids are two sets of genes ("alleles"), one from each parent. Who sequences Echoes - Ann - Island carrying out a gene expression will be different between different hybrids, and where they are located in the genome? Are they physically connected to the garden ("cis") as segments that initiate ("Fromotorim") operating genetic switches vivek consulting group that work? Or they are located in a remote location in the genome, and the influence it ("trans")? Using a technique developed to identify expression of individual alleles scientists examined expression patterns in human hybrids, and compared them to those of their parents. When the differences between the parents were kept to preserve the hybrid, the scientists concluded that distinguishing factor related to physical kindergarten affected ("cis"). These factors affect only the allele to which they are related. But, if there were different expression patterns between parent and parent and have identical hybrid Guard, the scientists concluded that the factors H"trns "located elsewhere in the genome, are responsible for the difference (these factors affect vivek consulting group Snihallim alike). vivek consulting group
Scientists have found that make a "cis" physically related genes were more affected by evolutionary changes: they were responsible for more than differences in gene expression processes, compared to factors that are located far from the area of impact ("trans"). Factors such as "cis" apparently were not affected by the way in which the yeast size. However, factors H"trns "were sensitive environment where grown yeast (showed significant differences between the growth in good conditions and an increase in miserable conditions). Also found that factors H"trns vivek consulting group "distant from the area where they affect, tend to settle in the genome in Barkai and members of her research team is headed by previously identified as open especially to evolutionary change.
But there are a large number of factors "trans" genome - transcription factors that bind directly to the gardens to absorb information vivek consulting group from the receptors to the cell environment. One of them underwent a change? Further research scientists were surprised to discover the most common changes were the parties engaged in sensing the environment and forwarding this information to the gardens. In other words, evolutionary response to changing conditions was way communication mechanisms of the cell with its environment. Proved again that the media guilty.
Scientists noticed, the yeast hybrids adapted Darwin's theory on the organisms that profit from being members - Hybrids (they have grown faster than their parents), and offered explanations for this. One possible explanation is based on the fact that the factor of "cis" and "trns "sometimes complement each other (factor" cis "weak one gene may borrow factor" vivek consulting group trans "is strong, and vice versa). In some cases, a combination of "cis" and "trns "strong second allele may cause overexpression garden. In this situation, the scientists expected to find one allele has a particularly vivek consulting group high level of expression. This, indeed, was the case in 20% of cases. In other cases there were two alleles have similar expression levels, but still beyond the range of the parents.
To their surprise, when identified the genes that act at the level of expression increased as a result of a cross between two species of yeast, scientists discovered that it was mainly the genes that play key roles in the same breath - the process by which yeast use sugar and sometimes oxygen to produce vivek consulting group energy. Species rarely use pure oxygen. They kept the gardens for breathing, but reduced their expression through the factor "trans". vivek consulting group Apparently, the combination of the two species vivek consulting group made these genes "come from the underground" and increase the level of activity of breathing apparatus. Such activities may have contributed to accelerated growth.
Mechanisms of new genetic expression patterns in mongrels may explain various differences between hybrids and their parents. Most hybrids vivek consulting group are sterile and unable to reproduce (eg Fred, who is a hybrid of a donkey and a horse). But, there are those who