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I learned that gene expression is the process by which the information of genes is used to direct the function of cells. Gene expression is regulated in all cells because not all genes are needed all the time or under all circumstances. For example, brain cells need to express certain genes that are not needed in muscle cells, and muscle cells need to express certain genes that are not needed in brain cells. Likewise, bacteria need to express different genes depending on the availability of food and other aspects of their surroundings.

n this interrupted case study, students learn about the influence of early fetal nutritional conditions on the expression of genes related to metabolism and growth. Beginning with the true event of a food and fuel embargo that led to famine in the western Netherlands toward the end of World War II, students learn about the historical background of the Dutch Hunger Winter and its social impact. Using real data from the study conducted by Heijmans and coauthors (2008), students then compare the methylation level of a specific gene between individuals conceived during the famine and their unaffected siblings, and how changes in the expression of this metabolically important gene may impact the risk of developing type 2 diabetes. Supported by other studies on mice and in humans, students conclude that in utero events may impact the health of individuals later in life through epigenetic mechanisms. The case is ideally suited for a molecular or cell biology course, but is also appropriate for an introductory biology course in which students have an understanding of descriptive statistics, interpretation of statistical test results, eukaryotic gene structure, and regulation of gene expression.

Unprecedented multiple and extreme-level resistance is generated in mosquitoes found in the rice fields of Tiassalé in southern Côte d'Ivoire. A new study highlights the combination of stringently-replicated whole genome transcription profiling, in vivo transgenic gene expression and in vitro metabolism assays to identify and validate genes from the P450 detoxification enzyme superfamily which are highly expressed in the adult females from the area.

"Some of the most exciting things that we've seen from looking at gene expression in space is that we really see an explosion, like fireworks taking off, as soon as the human body gets into space," Twins Study principal investigator Chris Mason said in a statement.

Almost every cell in your body has the same DNA sequence. So how come a heart cell is different from a brain cell? Cells use their DNA code in different ways, depending on their jobs. Just like orchestras can perform one piece of music in many different ways. A cell's combined set of changes in gene expression is called its epigenome. This week Nature publishes a slew of new data on the epigenomic landscape in lots of different cells. Learn how epigenomics works in this video. Read the latest research on epigenetics at http://www.nature.com/epigenomeroadmap

Through this method, the researchers were able to identify that the frizzled-6 gene was expressed around eight times more in tumor-forming cell lines. The specific cascade initiated by frizzled-6 and how it affects the development of cancerous cells has yet to be determined. The overexpression of frizzled-6 suggests that the protein either forms tumor cells directly or is an indirect result of other mutated pathways.

"This modular case study tells the story of Dan and Annie, a married couple of Acadian ancestry who have a genetic form of deafblindness called Usher syndrome. They live in Southwest Louisiana, home of the largest population of DeafBlind citizens in the United States. Acadian Usher syndrome is caused by an allele of the USH1C gene that came to Louisiana with the first Acadian settlers from Canada who founded today's Cajun population. This allele's single nucleotide substitution creates an erroneous splice site that produces a defective cytoskeletal protein (harmonin) of the cochlear and vestibular hair cells and retinal photoreceptors. This splice site is the target of a promising gene therapy. The case study applies and connects Mendelian inheritance, chromosomes, cell division, vision and hearing, DNA sequences, gene expression, gene therapy and population genetics to a specific gene and its movement through generations of Dan and Annie's families.  After the introduction, each of the remaining sections can be used independently either for in-class team activities or out-of-class extensions or assignments over an entire year of introductory undergraduate biology. "

In a study published Thursday in the journal Science, they report that they've pinpointed the bit of finch DNA behind the swift transition: a gene called HMGA2. In finches, HMGA2 seems to be the primary factor in beak size - like a really good group project leader, it orchestrates the expression of a number of other genes, each of which tweaks the size of the bird's beak. The same gene also appears in dogs, horses, even humans, holding sway over body size and stature.

Stem Cell Overview Article with embedded Video 7:53 Discusses gene expression/differentiation 2 minute segments -Pluripotent stem cells in early embryo CDX2 OCT3/4, Inner cell mass start- 1:50 - Characteristics of Stem Cells: differentiation, abilities of stem cells,  1:55- 3:17 - Stem Cells in the Adult Body: red blood cell hematopoetic stem cells, differentiation, small intestine crypts,  3:20-5:35 - Embryonic Stem Cells in Culture: ES pluripotent cells ES cells, treat to neural lineages, culture conditions, study differentiate into lineages 5:40- 7:53

transgenic expression of spider silk in milk

In this audio slide show, Dr. Dana Dolinoy of Duke University explains the role that the epigenome, a sort of second genome, plays in regulating the expression of our genes. As Dolinoy notes, we can no longer say with certainty whether genetics or the environment have a greater impact on our health, because the two are inextricably linked through the epigenome.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome.

Graham Williams at the University of Huddersfield, UK, has a different way - to look for modifications to the twins' DNA that have come about as a result of their lifestyles. Such epigenetic changes occur when a chemical group known as a methyl group attaches to a gene and modifies the way it is expressed. This happens as a body is influenced by a person's environment, lifestyle and disease.

Current CRISPR-based screens often mutate the beginning of a gene, which sometimes results in the expression of a functional protein variant. To circumvent this problem, researchers at Cold Spring Harbor Laboratory (CSHL) designed CRISPR guide RNAs that would mutate the portion of a gene encoding a domain on the surface of the protein where a small molecule could bind to alter the protein's function. The team had previously identified such a binding pocket on the protein BRD4, and a small molecule inhibitor that binds in the pocket is an effective leukemia treatment.

The activity of some of our genes varies with the seasons throughout the year. The discovery comes from an analysis of blood samples from more than 16,000 people in both hemispheres. The most striking pattern was that 147 genes involved in the immune system made it more reactive or "pro-inflammatory" during winter or rainy seasons, probably to battle the onslaught of cold and flu viruses

Early-response genes, which are important for synaptic plasticity, are "switched off" under basal conditions by topological constraints. Neuronal activity triggers DNA breaks in a subset of early-response genes, which overrides these topological constraints, and "switches on" gene expression.

Researchers at the University of Pennsylvania performed "stress tests" on pregnant mice using a predator's odor, restraint, or unfamiliar noises. After the mice gave birth, the scientists analyzed the bacterial communities in their vaginas and in their pups' colons. The researchers found that stress during pregnancy altered the expression levels of several proteins involved in vaginal immunity and the frequency of Lactobacillus bacteria, which, expectedly, correlated to lower frequencies of Lactobacillus within their pups' gut microbiomes. Male pups of stressed mothers also displayed an increase in anaerobic bacteria like Clostridium and Bacteroidesin.

Research on a modified protein around which DNA is wrapped sheds light on how gene regulation is linked to aging and longevity in nematodes, fruit flies and possibly humans. The research has implications for how gene expression is regulated, and could offer a new drug target for age-related diseases.

Even if you look like your mother, an innovative study suggests that not only humans but, in fact, all mammals are genetically more like Dad. We inherit equal amounts of genetic material from each parent, yet that coming from our father's side is more likely to take action, according to the study that was published in the journal Nature Genetics.

Epigenetics refers to heritable changes in gene expression caused by non-genetic mechanisms, thus by alterations other than in the DNA sequence. Epigenetic changes can persist throughout an organism's lifetime and be passed on to multiple generations. Site offers 4 part "crash course" in epigenetics