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Bad guy DNA
In evolution, everything is quite simple and cynical. If some genes increase the probability of leaving many offspring, then they will spread with each generation in the population more and more widely. If genes, on the contrary, reduce the likelihood of successful reproduction, then over time they will occur less and less. This principle concerns not only banal anatomy and physiology, but also behavior. We make any decisions by the brain, it consists of cells, the cells - of molecules, the composition of molecules is determined by genes. If some genes increase the likelihood of making a decision useful for the survival of the offspring, then their carrier will have more children who inherit the same valuable genes will also behave correctly, and so on.
The good news is that in the case of reproduction, there is no one right answer. If a man has genes that increase his desire for casual relationships, then this is certainly good - perhaps some of the seduced women will give birth to children from him. But if a man instead has genes that increase the likelihood of developing a strong attachment to his only woman, as well as a tendency to care for children born, then this may be even better because in such a situation the emergence of children and their continued survival is much easier to control. If a heartbreaker is very lucky with beauty, wealth, charm and independent mistresses, he may have ten children. But, if he is lucky a little less, he can not leave a single one. But a caring family man, with minimal effort, will find a woman willing to give birth to four of them, and at the same time all four will live to adulthood and be successful and prosperous, because two parents took good care of them.
All animals somehow balance between these strategies. The most convenient object to search for molecular mechanisms that increase or decrease the tendency of males to monogamy is again voles. I have already mentioned that the females of the steppe voles tend to become attached to a partner, although sometimes they change it. So, in this species there is complete equality: the males also spend a lot of time with their wives and children and take care of them. But in most genetically related species, for example, in meadow or mountain voles, nothing like this happens: males and females are found only for sex. Male does not show any interest to posterity, and females in general pay less attention to their children than in successful full families of steppe voles.
In the laboratory, love from voles is studied as follows: a young male virgin is placed in a cage for 24 hours together with the same young and inexperienced female. As a rule, six hours after they get to know each other are enough for the rodents to like each other, and they spend the rest of the day having sex (not continuously, but often). To then check whether the male has become attached to his partner, he is placed in a cage connected to two others: in one his first beloved lives, in the other - an unfamiliar female. The movements of the male are videotaped and calculate how much time he spent in each room. It turns out that experimenters have many ways to influence the emotional preferences of the male.
The most important role in the formation of attachment in males of the steppe vole is the release of dopamine in the nucleus accumbens. There are drugs that block dopamine receptors, such as the famous haloperidol, which has been used in psychiatric clinics for many years to soothe riot patients. So, if before the date the male of the steppe vole is given an injection of haloperidol, then he will mate with the female, but he will not have any attachment 11. No dopamine - no love, sorry. But if, on the contrary, before acquaintance with a female, to introduce an animal apomorphine, which increases the activity of dopamine receptors, attachment will arise even if there was no sex in six hours of contact.
Such experiments Brandon Aragon and Thomas Curtis, employees of the University of Florida, conducted in 2003. In their later works, it turned out that in fact the picture is even more complicated. At least two types of dopamine receptors, D1 and D2, are involved in the formation of attachment, and D2 stimulation causes attachment to the partner, and D1 is responsible for the other side of the coin - lack of interest (or even aggression) to other females. After the first meeting of the male monogamous vole with his future wife, he develops sympathy for her (that is, activation of the D2 receptors), and during the first weeks of living together in the male's brain, the activity of the D1 receptors gradually increases, and he loses all interest in other potential partners . Polygamic voles are not capable of such subtle feelings, because they initially had a different distribution of dopamine receptors in the brain.
While researchers from Florida continue to tinker with dopamine - make brain slices, select pharmacological drugs and introduce new females to monogamous and polygamous males, - Larry Young from Emory University came from the other side and already learned to turn polygamous meadow voles into devoted husbands with the help of gene therapy .
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Bad guy DNA
- Syndrome poor absorption of feed
Poor digestion syndrome (“pale bird syndrome”, brittle bone disease) is a viral etiology of chickens characterized by poor feathering, stunted growth, osteoporosis, and weak legs. Etiology. The causative agent of the disease is an RNA-containing complexly organized virus, family Reoviridae. Cultured in chicken embryos and cell culture of chicken fibroblasts.
- Peculiarities of behavior during the consultation of a good and bad counseling psychologist
A good psychologist-consultant -Tries to help the client to achieve certain goals by himself -Predlagdaet the client different ways of behavior and, if necessary, calls the client specific actions that should be done -Understands and is able to accept and recognize as correct act in accordance with it - understands, accepts and
- DNA probe
Diagnostic sites, stored on the basis of the analysis of genetic structures, are uniquely associated with the skin organ, and the name is DNA probe. Usi stinks based on the principles of complementarity of nucleotides (primers), synthesized by people. Sered metod_v assigned to the specific connection of such probes from the genome of the zudnik perche mytse for the responsiveness of the site polіmerazn lantsyugova
- Genomic DNA Restriction
For the restriction of genomic DNA, we used two types of restriction endonucleases (hereinafter referred to as restriction enzymes - Table 1). At the first stage, a certain amount of DNA from normal and tumor tissues was incubated with a restriction enzyme that did not contain CpG dinucleotides as part of its restriction site. Then, half or one third of the DNA thus treated was taken and restrictase sensitive to it was added to it.
- DNA replication
DNA replication (doubling). DNA is in the chromosomes, and its replication occurs before each doubling of chromosomes and cell division. J. Watson and F. Creek proposed a DNA doubling scheme, according to which the spiral-shaped double-stranded DNA first unwinds (unravels) along the axis. In this case, the hydrogen bonds between the nitrogenous bases break and the chains diverge. Simultaneously to the nucleotides of each
- Viral DNA
The main structural feature of most viral DNA molecules, as well as DNA from other sources, is the presence of two paired anti-parallel chains. The DNA genome of viruses, however, is small and therefore questions arise about the ends of the helix and the general shape of the DNA molecule, and not the monotonous, actually having no ends of the “middle” part of the helix. The responses received were quite
- Genetic strategies of DNA genomic viruses
In the process of replication, DNA-containing viruses carry out certain steps that are absent in RNA genomic viruses. For most DNA-containing viruses, genetic strategies include: transport of virion DNA into the cell nucleus, initiation of transcription from this DNA, induction of transcription of additional viral genes, preparation of the cell for virus replication, DNA duplication
- DNA re-precipitation (RNA)
To reprecipitate, 0.1 volume of 3 M sodium acetate pH 5.0 and 3 volumes of 96% ethanol were added to the DNA (RNA) solution, mixed thoroughly and kept at -20 ° C for 20 minutes. Then it was centrifuged at 13 thousand rpm for 5-15 minutes at 4 ° C. The DNA (RNA) precipitate was washed with 75% ethanol at 1 STE, dried under vacuum, and used further
- DNA methylation function
The most common function of methylation is to participate in cellular "immunity." For bacteria, it is characteristic as an element of the methylation-recognition system "friend-foe", which allows the cell to distinguish its genetic material from foreign molecules that have penetrated the cell. This allows you to maintain the genetic stability of the species. Sometimes one enzyme performs both methylase and endonuclear
- Recombinant DNA technology
On the cob of the 70s, the 20th century boules vivchennye primarypower of genetic systems. The bule was formed in the so-called “central dogma” form, since it is genetic, genetic information is transmitted from DNA to RNA that is far from a single one. Bula is identified by mRNA, genetic code is deciphered, identified by the main mechanisms of translation of mRNA in biloc. At one o'clock there was a view of the decal of the classes of ferments,
- Distribution of DNA methylation
Methylation of bases in DNA was discovered over 50 years ago and is observed in almost all classes of living organisms. The DNA of prokaryotes contains the modified bases ^-methyladenine and 5-methylcytosine, whereas for eukaryotes, the presence of mainly 5-methylcytosine is characteristic. It is present in the DNA of fungi and plants (Finnegan et al. 2000; Martienssen and Colot 2001). In the animal kingdom there is
- Isolation of DNA from leukocytes
The leukocyte mass was suspended in LST buffer. Added x equal volume 4 TNLB, gently mixed and centrifuged at 5 thousand rpm for 10 minutes. The precipitate was washed twice with LST-sucrose buffer. Then, TNE-1% SDS buffer and proteinase K at a final concentration of 100 μg / ml were added to the pellet. Incubated overnight at 50 ° C. Then added an equal volume of chloroform -
- Budova DNA molecule
Modern biotechnology should be characterized by yak biotechnology on the basis of genetic engineering. This is the main goal for the direction of modifying bioprojects into the result of the introduction of individual genetic programs. Spadkova іnformatsіya mіstitsya genome - the combination of genes (vipadku vіrusіv number of genes from 3-160) or organisms of chromosomes. Gene - dylyanka chromosome (abo DNA molecules abo RNA in viriv),