| 单词 | methyl group |
| 例句 | Removal of any one of the four hydrogen atoms from methane forms a methyl group. Chemistry 2019-02-14T00:00:00Z Instead, some genes were methylated, which simply means methyl groups were attached to certain nucleotides along the sequence. Biology for AP Courses 2022-06-09T00:00:00Z Three fatty acids, long chains of hydrocarbons with a carboxyl group and a methyl group at opposite ends, extend from each of the carbons of the glycerol. Anatomy and Physiology 2013-06-19T00:00:00Z One such mechanism, called methylation, involves a methyl group—a methane molecule that is missing one of its four hydrogen atoms, leaving a chemical bond free to attach to another atom or molecule. How Parents’ Trauma Leaves Biological Traces in Children 2022-06-25T04:00:00Z Their effects can vary: One editor might remove tags from histones to switch a gene on, whereas another might add methyl groups to DNA to repress it. Better than CRISPR? Another way to fix gene problems may be safer and more versatile 2022-06-01T04:00:00Z This makes it possible to have two isomers of 2-butene, one with both methyl groups on the same side of the double bond and one with the methyl groups on opposite sides. Chemistry 2019-02-14T00:00:00Z That idea began to unravel in 1994, when Low discovered that a chemical tag called a methyl group could block transcription in bacteria—something scientists had thought was exclusive to eukaryotic cells. Ancient Molecule Helps Bacteria Untangle Genetic Activity 2022-04-08T04:00:00Z The prefix “nor-” actually refers to this chemical difference, in which a methyl group is missing. Anatomy and Physiology 2013-06-19T00:00:00Z Methylation is a process by which, in the presence of specific enzymes, methyl groups attach to key sites on a strand of DNA or within the complex of DNA and proteins known as chromatin. How Parents’ Trauma Leaves Biological Traces in Children 2022-06-25T04:00:00Z Emerging evidence also suggests that DNA methylation—the addition of a methyl group to the DNA—might be the link between the conditions a fetus is exposed to in the womb and later obesity. How a Child’s Heart Health Could Be Decided before Birth 2021-11-30T05:00:00Z In DNA methylation, a molecule called a methyl group attaches to a base, usually cytosine. Chemical on-off switches for genes may help explain why large mammals live longer 2021-10-18T04:00:00Z Patterns of chemical tags called methyl groups glom onto genes, turning them on or off. Identical twins carry genetic modifications no one else has 2021-09-28T04:00:00Z Arsenic may influence whether methyl groups are added to specific DNA sequences. New Technologies Could Protect Against Arsenic Toxicity in Water 2021-03-11T05:00:00Z By occupying these sites like roadblocks on a highway, methyl groups can alter transcription, a basic step in gene expression where a piece of RNA is made from a DNA template. How Parents’ Trauma Leaves Biological Traces in Children 2022-06-25T04:00:00Z So in the new study, a team of international researchers from Peru, Germany, and the United States looked at an epigenetic process called methylation, in which cells add chemical tags called methyl groups to DNA. High-altitude living has changed more than just the genes of some Peruvians 2020-12-22T05:00:00Z Horvath is known for showing that patterns of these methyl groups change as a person ages, and for creating an “epigenetic clock” that uses a DNA sample to estimate a person’s age within 3.6 years. Chemical on-off switches for genes may help explain why large mammals live longer 2021-10-18T04:00:00Z When the researchers looked at methylation patterns—the DNA location of chemical tags called methyl groups that regulate gene expression—they found that changes caused by the injury resembled those in aging mouse cells. Researchers restore lost sight in mice, offering clues to reversing aging 2020-12-02T05:00:00Z Modifications at the C4 methyl group would be challenging to accomplish by semisynthesis, but were sitting ducks for Li and colleagues’ modular approach. Modular synthesis enables molecular ju-jitsu in the fight against antibiotic resistance 2020-09-22T04:00:00Z The researchers showed that when they inhibited a protein that removes adenine’s methyl groups, causing methyladenine to accumulate, tumor growth slowed. Controversial DNA modification could play key role in placenta development 2020-07-23T04:00:00Z As animals get older, tiny chemical tags called methyl groups get added and removed from DNA. To estimate your dog’s age in human years, you’re going to have to learn a bit more math 2020-07-10T04:00:00Z Liu is part of an academic group running studies of another blood test, developed by the biotech Grail, which looks at patterns of methyl groups on cell-free DNA to detect cancers. Blood tests spot cancers before symptoms appear, but also produce false positives 2020-04-26T04:00:00Z But big questions remain, he says: How do these factors cause methyl groups to be added or removed? Researchers restore lost sight in mice, offering clues to reversing aging 2020-12-02T05:00:00Z After replacing a hydrogen with an oxygen, it steals a methyl group from a reagent known as trimethylaluminum and inserts it in oxygen’s place. Newly discovered ‘magic methyl’ reaction could turbocharge the potency of some drugs 2020-03-16T04:00:00Z These include processes that add or remove either methyl groups on DNA or acetyl groups on DNA-binding proteins called histones. Tweaking the DNA of myeloid cells curbs cancer spread 2020-02-25T05:00:00Z Many of the early mammalian epigenetics studies focused on DNA methylation, which "tags" DNA with methyl groups that switch genes off. Parents’ emotional trauma may change their children’s biology. Studies in mice show how 2019-07-18T04:00:00Z Their teams focused on one mRNA modification called m6A: a methyl group—a simple chemical unit—attached to some of an RNA molecule’s adenine bases. Hidden layer of gene control influences everything from cancer to memory 2019-07-01T04:00:00Z Me-His is an analogue of histidine in which a methyl group is attached to one of the nitrogen atoms in the side chain. Catalytic machinery of enzymes expanded 2019-05-26T04:00:00Z White wanted to find a way to add a methyl group at the end of the drug building process. Newly discovered ‘magic methyl’ reaction could turbocharge the potency of some drugs 2020-03-16T04:00:00Z Notably, the enzymes responsible for transferring the first, second and third methyl groups to this lysine residue are unique11. Modification of histone proteins by serotonin in the nucleus 2019-03-12T04:00:00Z It is based on a process known as epigenetics - the attachment of a chemical tag known as a methyl group to DNA. Blood test can detect cancer in 10 minutes, researchers claim 2018-12-05T05:00:00Z Whereas the lysine is modified chemically — by the addition or removal of a methyl group — to regulate gene expression, the methionine is not. The unexpected role of histones in childhood brain cancer 2018-09-25T04:00:00Z However, analogues in which a methyl group is attached next to the carbonyl group were poor substrates. Catalytic machinery of enzymes expanded 2019-05-26T04:00:00Z These are chemical modifications, such as the attachment of methyl groups, that are made to DNA and to the histone proteins that associate with it to form chromatin. Neighbourhood deaths cause a switch in cancer subtype 2018-09-11T04:00:00Z They took a machine-learning approach to tumour classification based on changes in DNA methylation — the addition of methyl groups to DNA — and compared such diagnoses with those made by pathologists using histological analysis. Machine learning classifies cancer 2018-03-13T04:00:00Z They discovered cancer cells' genome is essentially barren except for intense clusters of methyl groups at very specific locations - instead of being spread evenly like in normal cells. Blood test can detect cancer in 10 minutes, researchers claim 2018-12-05T05:00:00Z Moreover, the K27M mutation affects not only the histone gene in which it occurs; in fact, the methionine broadly inhibits the enzyme that adds methyl groups to lysines in histones. The unexpected role of histones in childhood brain cancer 2018-09-25T04:00:00Z Lumey and his colleagues propose that these methyl groups disrupt how cells normally use genes. Dutch genes still bear scars of a famine 2018-02-16T05:00:00Z Dr. Lumey and his colleagues propose that these methyl groups disrupt how cells normally use genes. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z Anstee’s group is looking at epigenetic marks consisting of methyl groups on DNA from genes expressed mainly in liver cells that circulates freely in blood. Disease progression: Divergent paths Maden, B. E. Identification of the locations of the methyl groups in 18 S ribosomal RNA from Xenopus laevis and man. Visualization of chemical modifications in the human 80S ribosome structure 2017-11-14T05:00:00Z The presence of N1 methyl groups on adenine bases was thought to be widespread in messenger RNAs. Epitranscriptomics: Shrinking maps of RNA modifications 2017-10-24T04:00:00Z But Heijmans and his colleagues studied the same methyl groups in muscle cells, fat cells and other tissues they got from cadavers. Dutch genes still bear scars of a famine 2018-02-16T05:00:00Z One methyl group that is linked to a higher body mass index may be able to quiet a gene called PIM3, which is involved in burning the body’s fuel. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z Others are looking for epigenetic alterations associated with the disease — changes in the number or types of chemical tag, such as methyl groups, that attach to specific sites in DNA and influence gene expression. Diagnostics: A flow of information 2017-11-07T05:00:00Z Maden, B. E. Locations of methyl groups in 28 S rRNA of Xenopus laevis and man: clustering in the conserved core of molecule. Visualization of chemical modifications in the human 80S ribosome structure 2017-11-14T05:00:00Z These are steroids that differ by only one methyl group and show some cross-reactivity with their nuclear receptors. Opinion | Marshall ought to do more research on gender 2017-10-03T04:00:00Z They then treated the nuclei with a chemical that converts cytosines without methyl groups to the RNA base uracil. Method that Maps DNA Tags Reveals New Types of Neurons 2017-09-18T04:00:00Z At millions of spots across our DNA, genes may carry a methyl group. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z Modification of methyl groups attached to DNA alters gene expression, and mutations that deregulate this methylation are common in some leukaemias. Cancer therapy: The leukaemia epigenome targeted : Nature : Nature Research 2017-03-28T04:00:00Z A DEA chemist demonstrates by snapping a methyl group onto a plastic model of fentanyl. Underground labs in China are devising potent new opiates faster than authorities can respond 2017-03-29T04:00:00Z Fritz Rottman, an organic chemist at Michigan State University in East Lansing, was trying to understand the role of RNA in regulating gene expression when he stumbled across a methyl group on adenine. An epigenetics gold rush: new controls for gene expression 2017-02-21T05:00:00Z They sequenced the DNA to pinpoint the remaining cytosines, yielding a map of every methyl group. Method that Maps DNA Tags Reveals New Types of Neurons 2017-09-18T04:00:00Z Many researchers have speculated that prenatal conditions can influence people’s health across their lifetime, and some have speculated that methyl groups or other forms of epigenetics put this so-called fetal programming into action. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z The best-studied of these 'epigenetic' marks are methyl groups that, when added to or removed from DNA, boost or silence gene activity. Secrets of life in a spoonful of blood 2017-02-06T05:00:00Z The team then fused the disabled Cas9 to enzymes that either add or remove methyl groups. Epigenetics: CRISPR edits gene methylation : Nature : Nature Research 2016-09-27T04:00:00Z Looking at RNA in a NMR machine, Al-Hashimi noticed that adding a methyl group — and prompting the RNA strand to unravel — actually made it more efficient in this task. A weird twist in DNA might explain why it’s such a great blueprint for life 2016-08-01T04:00:00Z The sequencing step allowed the researchers to determine which genes are under the control of methyl groups in each type of neuron. Method that Maps DNA Tags Reveals New Types of Neurons 2017-09-18T04:00:00Z They retrieved DNA from the samples and placed it in a device able to find methyl groups at nearly 350,000 spots on the genome. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z He decided to test this idea by studying chemical tags known as methyl groups, which alter DNA structure to regulate how genes are expressed. Poverty linked to epigenetic changes and mental illness 2016-05-23T04:00:00Z The authors found that removing methyl groups from two specific regions induced the expression of certain genes. Epigenetics: CRISPR edits gene methylation : Nature : Nature Research 2016-09-27T04:00:00Z He and his colleagues added a methyl group to a strand of RNA to see what happened. A weird twist in DNA might explain why it’s such a great blueprint for life 2016-08-01T04:00:00Z But two methyl group arrangements point to unique gene-expression profiles, hinting at two previously unrecognized types of neurons. Method that Maps DNA Tags Reveals New Types of Neurons 2017-09-18T04:00:00Z They searched for methyl groups that were common in the Dutch Hunger Winter cohort, for example, but missing from their siblings. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z He also describes how the attachment of chemical groups called methyl groups to DNA can change gene activity. Researcher under fire for New Yorker epigenetics article 2016-05-08T04:00:00Z One involved the addition of a chemical side chain, called a methyl group, to DNA. The Science of Identity and Difference 2016-05-02T04:00:00Z It keeps track of age-related changes in molecules, called methyl groups, that attach to the outside of our strands of DNA, like barnacles on a rope dangling off a dock. Scientists can make mice live longer. Now they want to do the same for you. 2016-04-18T04:00:00Z When the IDH gene was mutated, the cancer cells’ DNA became studded with chemical tags known as methyl groups. Brain Cancers Reveal Novel Genetic Disruption in DNA 2015-12-23T05:00:00Z They sorted people according to their body mass index, for example, and looked for methyl groups that were unusually common in overweight people. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z Whereas other drugs treat cancer by blocking enzymes that remove methyl groups from DNA. Epigenetics: The genome unwrapped : Nature : Nature Publishing Group 2015-12-01T05:00:00Z Yet, as DNA methyl groups or histone modifications get shifted around those gene sequences, the worker transforms into a gamergate, and virtually everything about the insect’s physiology and behavior changes. The Science of Identity and Difference 2016-05-02T04:00:00Z This research, just published in the Proceedings of the National Academy of Sciences, looked at DNA methylation, a phenomenon which involves the addition of chemicals called methyl groups to genetic material in chromosomes. No good deed goes unpunished 2015-07-16T04:00:00Z Dr. Bernstein and his colleagues tested their hypothesis by growing glioma cells in petri dishes and adding a rarely used first-generation chemotherapy drug, 5-Azacytidine, that dissolves methyl groups. Brain Cancers Reveal Novel Genetic Disruption in DNA 2015-12-23T05:00:00Z Finally, the researchers merged the results — and found a few methyl groups that were linked both to the famine and to health conditions later in life. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z The most common way of controlling this gene expression is by plunking a molecule known as a methyl group on the promoter region. All About Epigenetics: The Other Way You Inherit Disease Risk 2015-06-08T04:00:00Z The methyl groups hang off the DNA string like Christmas ornaments, and specific proteins add and remove the ornaments, in effect “decorating” the genome. The Science of Identity and Difference 2016-05-02T04:00:00Z Epigenetic alterations are chemical tags such as methyl groups that are added to or removed from genes to turn them off or on. Animal behaviour: Nested instincts : Nature : Nature Publishing Group 2015-05-19T04:00:00Z Genes may be switched off, or silenced, by the attachment of molecular caps called methyl groups, a process called methylation. Parasites Practicing Mind Control 2014-08-28T04:00:00Z So here’s the theory: Perhaps the Dutch Hunger Winter added a methyl group to fetuses born to starving mothers, which made the PIM3 gene less active — and continued to do so for life. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z The change involved adding chemicals, known as methyl groups, to the gene. Could a Blood Test Predict Suicide Risk? 2014-07-30T04:00:00Z Yet most methyl groups are removed with formation of an embryo, and only a small number of genes are known to escape this process. Starvation in pregnant mice marks offspring DNA 2014-07-09T04:00:00Z The authors say those changes in methyl group additions were likely the cause of diabetes-like symptoms in the mice. Diet during Pregnancy Linked to Diabetes in Grandchildren 2014-07-10T04:00:00Z One such modification involves tagging gene regions with chemical compounds called methyl groups and results in silencing the genes. Is what you eat before pregnancy important? 2014-05-27T04:00:00Z One of the best studied is a molecular cap called a methyl group. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z The termite genome also contains a high fraction of genes that are turned off by chemical tags, or methyl groups, the researchers found. Termite Genome Reveals Details of "Caste System" 2014-05-20T04:00:00Z One such modification involves attaching chemicals called methyl groups to DNA. Pre-pregnancy diet 'affects genes' 2014-04-30T01:10:52Z One such modification involves tagging regions of DNA with chemical compounds called methyl groups. Pre-pregnancy diet 'affects genes' 2014-04-30T01:10:52Z In human DNA, methyl groups most often attach at 'CpG sites' — places where a cytosine precedes a guanine in the DNA. Biomarkers and ageing: The clock-watcher 2014-04-09T17:20:26.613Z They seem to silence genes — at least, researchers have found that silenced genes often have a collection of methyl groups lurking nearby. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z They look at differences in the distribution of methyl groups at thousands of specific DNA nucleotides across the genome to identify arrangements that are common in a disease, or associated with variation in a trait. Epigenomics starts to make its mark 2014-04-02T17:20:26.967Z Acetyl and methyl groups can attach to histones and affect the expression of nearby DNA. Epigenetics: The sins of the father 2014-03-05T18:50:37.761Z Szyf had been tracking the addition and removal of methyl groups to DNA, which can silence or activate genes. Behaviour and biology: The accidental epigeneticist 2013-12-31T14:20:21.368Z To determine a person's age, Horvath explores data for hundreds of far-flung positions on DNA from a sample of cells and notes how often those positions are methylated — that is, have a methyl group attached. Biomarkers and ageing: The clock-watcher 2014-04-09T17:20:26.613Z Over a decade later, he and his colleagues were able to take advantage of powerful new technology for detecting methyl groups in blood cells. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z Methylation — the addition of methyl groups — tends to suppress the activity of genes. Epigenomics starts to make its mark 2014-04-02T17:20:26.967Z Afterward, a second muscle biopsy showed that DNA methylation patterns in the muscle cells were already changing after that lone workout, with some genes gaining methyl groups and some losing them. Well: How Exercise Changes Fat and Muscle Cells 2013-07-31T04:01:56Z The AA gene variant, the researchers report online today in The Journal of Clinical Investigation, removed more methyl groups from the gene, leading to increased levels of the hunger hormone. Obesity Gene Linked to Hunger Hormone 2013-07-15T18:00:00Z One of these enzymes, DNMT3A, adds methyl groups to DNA and was found to be mutated in 51 of the 200 patients. Epigenetics: Reversible tags 2013-06-26T17:20:55.210Z But Dr. Heijmans and his colleagues studied the same methyl groups in muscle cells, fat cells and other tissues they got from cadavers. The Famine Ended 70 Years Ago, but Dutch Genes Still Bear Scars 2018-01-31T05:00:00Z The notes essentially said things such as: "This part binds a protein"; "This part is often tagged with methyl groups"; and "This part is usually tucked away, wound around a protein called a histone." Friction over Function: Scientists Clash on the Meaning of ENCODE s Genetic Data 2013-04-12T10:45:00.533Z Some molecules, such as methyl groups, physically block cellular machinery from reading the genetic instructions in certain segments of DNA; some enzymes loosen the bonds between histones and DNA, making particular genes more accessible. Will Cloning Ever Save Endangered Animals? 2013-03-11T11:15:00.737Z But when Liebl combed the genomes of the birds to look for parts that had methyl groups attached — a key epigenetic marker — she found a high level of variability across populations. Epigenetics Posited as Important for Success of Invasive Species 2013-01-10T18:15:02.317Z Compared with people who had never smoked, these individuals had fewer chemical tags known as methyl groups—a common type of epigenetic change—on 20 different regions of their DNA. Smoking Smothers Your Genes 2012-12-21T19:15:00Z Drought and poor nutrition are known to cause so-called epigenetic changes to DNA, the addition or removal of small chemical tags known as methyl groups that effectively turn genes on or off. Inbreeding's Downside Is Not All in the Genes 2012-07-11T00:20:00Z He noted remarkable changes wrought by the swapping of one methyl group in biology. How to Succeed in Science: Lindau Nobel Laureate Meeting, Day 4 2012-07-05T15:45:00.413Z Adding small chemicals, methyl groups, to specific points of DNA is one of the main ways of turning a gene off. Ageing in centenarians and newborns 2012-06-14T23:55:06Z One of the most common of these epigenetic changes involves a methyl group -- one carbon atom and three hydrogen atoms—binding to a nucleotide, usually cytosine. Aging Is Recorded in Our Genes 2012-06-11T20:10:00Z Environmental factors can place shielding methyl groups directly onto DNA, blocking expression of certain genes. 10 Things Exome Sequencing Can t Do-But Why It s Still Powerful 2012-05-16T13:45:00.180Z To show that methylation was a cause rather than an effect of inbreeding depression, the researchers treated another batch of inbred Scabiosa with a chemical called 5-azacytidine, which removes methyl groups from DNA. Inbreeding's Downside Is Not All in the Genes 2012-07-11T00:20:00Z In a mutation that changes one methyl group, an XY baby has a female anatomy but is infertile. How to Succeed in Science: Lindau Nobel Laureate Meeting, Day 4 2012-07-05T15:45:00.413Z For example, adding methyls to DNA tends to decrease the gene expression of that DNA segment, while taking away methyl groups increases it. Methylating Your Muscle DNA 2012-05-14T12:15:00.237Z This enzyme attaches methyl groups to histone proteins, which are part of the chromosomal packaging. Cancer and epigenetics: Cancer?s epicentre 2012-04-03T16:18:14Z The more intense the exercise, she says, the more the methyl groups are on the move. Exercise Breakthrough: How Working Out Alters DNA 2012-03-07T20:06:22Z Vergeer speculates that the abnormal methylation might result from some of the rare genes exposed by inbreeding, especially if these genes help regulate the attachment and removal of methyl groups. Inbreeding's Downside Is Not All in the Genes 2012-07-11T00:20:00Z “What would our society be if a methyl group was not where it is now?” How to Succeed in Science: Lindau Nobel Laureate Meeting, Day 4 2012-07-05T15:45:00.413Z Certain epigenetic modifications, such as the binding of methyl groups to histone proteins, the bobbins around which DNA is wound for chromatin packaging, are responsible for holding the fiber in an open state. Epigenetics: A Turning Point in our Understanding of Heredity 2012-01-16T16:45:00.190Z “Why yes,” you organic chemistry nerds may say, “It clearly is a molecule of sulfur with two methyl groups attached.” Chemistry Day at Scientific American Blog Network 2011-08-02T17:45:00.247Z The muscle biopsies following the 80% sessions showed a lower concentration of methyl groups — and therefore more RNA, which is the first byproduct of gene activity — than samples taken after the 40% sessions. Exercise Breakthrough: How Working Out Alters DNA 2012-03-07T20:06:22Z Small chemicals called methyl groups bind to the DNA, helping to determine which genes become active. Spit Analysis Reveals Hocker's Age 2011-06-22T22:15:00.450Z One methyl group also makes the difference between estrogen and testosterone. How to Succeed in Science: Lindau Nobel Laureate Meeting, Day 4 2012-07-05T15:45:00.413Z Often these are chemical tags called methyl groups that can bind to DNA, where they act a bit like a volume knob, turning up or down the activity of certain genes. Why Skinny Moms Sometimes Produce Fat Children 2011-04-22T16:45:52Z Just a sulfur molecule with two methyl groups attached. Chemistry Day at Scientific American Blog Network 2011-08-02T17:45:00.247Z Here, chemical compounds called methyl groups attach to regions of DNA and, like a volume knob on a stereo, turn the activity of a gene up or down. A Safer Way to Spot Down Syndrome 2011-03-06T18:00:00Z In healthy cells a compound called a methyl group is tagged to DNA where it acts as a "red light", preventing certain genes from producing proteins. Hope for early bowel cancer test 2011-03-05T02:52:27Z One possible answer lies in epigenetics: the chemical footprints, such as methyl groups, stamped on DNA by early life events that alter gene-expression patterns and might contribute to later disease. Epidemiology: Study of a lifetime 2011-03-02T18:20:50.637Z A recent survey of methyl groups on the DNA of adult people has also suggested that these tags are linked to obesity. Why Skinny Moms Sometimes Produce Fat Children 2011-04-22T16:45:52Z The genomes also revealed that adding or removing chemical tags called methyl groups to or from a handful of genes to turn them off or on determines an ant's fate in the social ladder. An Army of Ant Genomes 2011-01-31T20:01:00Z The team found that the enzyme also adds methyl groups to proteins involved in cutting and pasting RNA molecules that will later be made into proteins. Splices of Time 2010-10-20T18:11:00Z All cells switch off the genes they do not need by attaching small chemicals called methyl groups to certain sites along their DNA. DNA Test May Speed Colon Cancer Diagnosis 2010-08-09T23:38:00Z But what if flooding the fetus with methyl groups turns off healthy genes? 2010-01-14T17:38:00Z Darwin taught us that it takes many generations for a genome to evolve, but researchers have found that it takes only the addition of a methyl group to change an epigenome. 2010-01-08T21:15:00Z The difference between these two bases is one methyl group: thymine is a 5-methyluracil. History of Phosphorus By adding methyl groups to proteins involved in selecting where to cut the RNA molecule, the interaction with some weak cutting sites is strengthened, the researchers discovered. Splices of Time 2010-10-20T18:11:00Z Careful studies of its addition and oxidation products prove that it has the following structural arrangement: As this formula indicates, the compound contains one unsaturated, double-bond linkage, one primary alcohol group, and eleven methyl groups. The Chemistry of Plant Life We derived this substance from ethane by introducing a methyl group; hence it may be termed “methylethane.” Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1 "Châtelet" to "Chicago" A methyl group is a basic unit in organic chemistry: one carbon atom attached to three hydrogen atoms. 2010-01-08T21:15:00Z The spinal and muscular hyperic excitability produced by caffein is, in his opinion, due to the methyl groups attached to the xanthin nucleus. All About Coffee If we assume that such groups are derived ultimately from levulose, we have to account for the detachment of the methyl group. Researches on Cellulose 1895-1900 The B vitamins acted as methyl donors: they caused methyl groups to attach more frequently to the agouti gene in utero, thereby altering its expression. 2010-01-08T21:15:00Z The hydroxyl group also resembles the methyl group in its morphotropic effects, producing, in many cases, no change in symmetry but a dimensional increase in one direction. Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1 "Châtelet" to "Chicago" When a methyl group attaches to a specific spot on a gene — a process called DNA methylation — it can change the gene's expression, turning it off or on, dampening it or making it louder. 2010-01-08T21:15:00Z |
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