diabetestalk.net

Where Does The Insulin Gene Come From?

Where Does Insulin Come From?

Where Does Insulin Come From?

Diabetes Forum • The Global Diabetes Community Find support, ask questions and share your experiences. Join the community » Not your own body produced. I mean the stuff given to inject yourself. I've been told it's from pigs. Is that true? The first successful insulin preparations came from cows (and later pigs). The pancreatic islets and the insulin protein contained within them were isolated from animals slaughtered for food in a similar but more complex fashion than was used by our doctor and med-student duo. The bovine (cow) and porcine (pig) insulin were purified, bottled, and sold. Bovine and porcine insulin worked very well (and still do!) for the vast majority of patients, but some could develop an allergy or other types of reactions to the foreign protein (a foreign protein is a protein which is not native to humans). In the 1980's technology had advanced to the point where we could make human insulin. The advantage would be that human insulin would have a much lower chance of inducing a reaction because it is not a foreign protein (all humans have the exact same insulin, so we do not "see" this as a foreign protein). The technology which made this approach possible was the development of recombinant DNA techniques. In simple terms, the human gene which codes for the insulin protein was cloned (copied) and then put inside of bacteria. A number of tricks were performed on this gene to make the bacteria want to use it to constantly make insulin. Big vats of bacteria now make tons of human insulin. From this, pharmaceutical companies can isolate pure human insulin. There are currently 3 Types of Insulin available in the UK. Then within each type there are a variety of insulin’s, which differ in the way they act and/or how long they last. Genetically Modified Continue reading >>

Genetic Testing Can Help Some Diabetics Stop Taking Insulin

Genetic Testing Can Help Some Diabetics Stop Taking Insulin

If you or a loved one have diabetes, you may be familiar with the struggles of insulin therapy. Calculating your dose and injecting yourself isn’t fun, of course. And if you forget to bring your shots with you, it can turn into a medical emergency. But studies have revealed that up to 5 percent of individuals with diabetes have an inherited form that is responsive to different types of medications and may actually eliminate the need for insulin injections. This form of diabetes is sometimes referred to as “Type 3” or “Type 1.5,” but it’s more often known as Maturity Onset Diabetes of the Young (MODY). MODY is often undiagnosed due to its similarities to both Type 1 and Type 2 diabetes. In fact, the only way to properly identify MODY is through genetic testing. To understand MODY, it’s important to understand diabetes in general. It all starts with insulin. When you eat a meal, sugar from the food enters your bloodstream where it can be used by your cells, but they require insulin to do so. Insulin is made in the pancreas in beta cells, which sense sugar in the blood and respond by releasing insulin, thereby helping the body get energy. Diabetes develops when either a person’s pancreas makes too little insulin, or their cells don’t respond properly to the insulin that’s produced. This results in high levels of sugar in the bloodstream, because the sugar can’t enter the body’s cells. In Type 1 diabetes, this happens because the pancreas doesn’t release enough insulin; in Type 2 diabetes, cells resist the insulin that is produced. The causes of MODY include both of these mechanisms. MODY is a genetic diagnosis that involves a change in the DNA inherited from your parents. The most common form of this condition comes from a variation in a gene call Continue reading >>

Cloning Insulin

Cloning Insulin

In 1978, Genentech scientist Dennis Kleid toured a factory in Indiana where insulin was being made from pigs and cattle. “There was a line of train cars filled with frozen pancreases,” he says. At the time, it took 8,000 pounds of pancreas glands from 23,500 animals to make one pound of insulin. Diabetics lack this hormone, which regulates the amount of glucose in the blood. The manufacturer, Eli Lilly, needed 56 million animals per year to meet the increasing U.S. demand for the drug. They had to find a new insulin alternative, fast. Genentech had the expertise to make synthetic human insulin—in laboratories, from bacteria, using their recently-proven recombinant DNA technology. But could they make enough of the miniscule insulin molecules to replace these trainloads of pancreases and provide an alternative option for people living with diabetes? The scientists would have to coax the bacteria to produce insulin from the synthetic DNA at high enough concentrations to make an economically viable product. This meant that each bacteria needed to churn out so much of the protein per cell that if they could do it, they’d look like stuffed olives under a microscope. If not, Genentech’s work would have ended as a scientific curiosity, with no new option for diabetics. I don’t want to hear that word, impossible...tell me what you need to get it done. Kleid didn’t think they could get that kind of yield. He told Genentech founder, Bob Swanson, flat-out that it couldn’t be done. But Swanson refused to accept it. “I don’t want to hear that word, impossible,” he told Kleid. “Tell me what you need to get it done.” The high-stakes, high-pressure race to create synthetic insulin had started over a year earlier. Eli Lilly, the main U.S. producer of insulin, ha Continue reading >>

Regulation Of The Insulin Gene By Glucose And Fatty Acids

Regulation Of The Insulin Gene By Glucose And Fatty Acids

Regulation of the Insulin Gene by Glucose and Fatty Acids Department of Medicine, University of Montreal, Montreal, QC, Canada Centre de Recherche du Centre Hospitalier de l'Universite de Montreal, QC, Canada To whom correspondence should be addressed. E-mail: [email protected] . Search for other works by this author on: Centre de Recherche du Centre Hospitalier de l'Universite de Montreal, QC, Canada Search for other works by this author on: Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN Search for other works by this author on: Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN Search for other works by this author on: Pacific Northwest Research Institute, Seattle, WA Departments of Medicine and Pharmacology, University of Washington, Seattle, WA Search for other works by this author on: Pacific Northwest Research Institute, Seattle, WA Search for other works by this author on: The Journal of Nutrition, Volume 136, Issue 4, 1 April 2006, Pages 873876, Vincent Poitout, Derek Hagman, Roland Stein, Isabella Artner, R. Paul Robertson, Jamie S. Harmon; Regulation of the Insulin Gene by Glucose and Fatty Acids, The Journal of Nutrition, Volume 136, Issue 4, 1 April 2006, Pages 873876, The insulin gene is expressed almost exclusively in pancreatic -cells. Metabolic regulation of insulin gene expression enables the -cell to maintain adequate stores of intracellular insulin to sustain the secretory demand. Glucose is the major physiologic regulator of insulin gene expression; it coordinately controls the recruitment of transcription factors [e.g., pancreatic/duodenal homeobox-1 (PDX-1), mammalian homologue of avian MafA/L-Maf (MafA), Beta2/Neuro D (B2), the r Continue reading >>

Pancreatic -cell-specific Repression Of Insulin Gene Transcription By Ccaat/enhancer-binding Protein

Pancreatic -cell-specific Repression Of Insulin Gene Transcription By Ccaat/enhancer-binding Protein

Pancreatic -Cell-specific Repression of Insulin Gene Transcription by CCAAT/Enhancer-binding Protein INHIBITORY INTERACTIONS WITH BASIC HELIX-LOOP-HELIX TRANSCRIPTION FACTOR E47 * From the Laboratory of Molecular Endocrinology, Massachusetts General Hospital, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02114 Chronic exposure of -cells to supraphysiologic glucose concentrations results in decreased insulin gene transcription. Here we identify the basic leucine zipper transcription factor, CCAAT/enhancer-binding protein (C/EBP), as a repressor of insulin gene transcription in conditions of supraphysiological glucose levels. C/EBP is expressed in primary rat islets. Moreover, after exposure to high glucose concentrations the -cell lines HIT-T15 and INS-1 express increased levels of C/EBP. The rat insulin I gene promoter contains a consensus binding motif for C/EBP (CEB box) that binds C/EBP. In non--cells C/EBP stimulates the activity of the rat insulin I gene promoter through the CEB box. Paradoxically, in -cells C/EBP inhibits transcription, directed by the promoter of the rat insulin I gene by direct protein-protein interaction with a heptad leucine repeat sequence within activation domain 2 of the basic helix-loop-helix transcription factor E47. This interaction leads to the inhibition of both dimerization and DNA binding of E47 to the E-elements of the insulin promoter, thereby reducing functionally the transactivation potential of E47 on insulin gene transcription. We suggest that the induction of C/EBP in pancreatic -cells by chronically elevated glucose levels may contribute to the impaired insulin secretion in severe type II diabetes mellitus. Insulin is a hormone essential for the control of mammalian glucose homeostasis and is Continue reading >>

Ocr Gateway Triple Science Topics

Ocr Gateway Triple Science Topics

Genetic engineering can be used to create organisms that produce large amounts of useful substances - for example, bacteria can be engineered to produce human insulin to treat diabetics. Genetic engineering can also be used to create and store DNA fingerprints, which can be used for identification purposes. Genetic engineering Genetic engineering involves altering the genetic code of an organism by inserting a gene or genes from another organism. Bacteria can be genetically engineered (genetically modified) to produce useful human proteins including human growth hormone and human insulin. One advantage of using bacteria is that they can be grown in large fermenters, producing large amounts of these useful proteins. You should be able to describe the main stages in genetic engineering, and in particular how this works for engineering bacteria to produce human insulin. Main stage Insulin example Desired gene is identified Human insulin gene is identified The gene is removed from the organism’s DNA The gene for making human insulin is cut out of some human DNA The DNA in other organism is cut open A loop of bacterial DNA is cut open The gene is inserted into the cut DNA The human insulin gene is inserted into the cut loop, and this loop is inserted into a bacterial cell The inserted gene works in the transgenic (genetically engineered) organism The bacterial cell produces human insulin The transgenic organism is cloned to produce lots of identical copies The transgenic bacterium is cloned to make lots of copies Large amounts of human insulin is collected The animation shows how this works. You have an old or no version of Flash - you need to upgrade to view this content! Go to the WebWise Flash install guide DNA fingerprinting A person’s DNA is unique to them. Their DN Continue reading >>

The Insulin Gene Is Located On Chromosome 11 In Humans

The Insulin Gene Is Located On Chromosome 11 In Humans

The polypeptide hormone insulin is required for normal glucose homeostasis. Insulin deprivation results in diabetes, a disease affecting up to 5% of the human population1,2. In some animals there are two insulin genes3; however, in most others, including humans, a single gene is present. The conclusion that there is a single insulin gene in humans is based on the finding of a single insulin species and on genetic studies involving mutant insulin alleles4,5. As the pattern of inheritance of insulin defects is not sex linked, the insulin gene must be located on an autosomal chromosome5. Recently, genomic DNA segments containing the human and rat insulin genes have been cloned and the DNA has been sequenced6–8. The fact that mouse and rat insulins are identical3 suggests that the insulin gene sequences and organization are similar. A knowledge of the restriction endonuclease map for the human and mouse insulin genes enables human or mouse insulin DNA sequences to be distinguished in somatic cell hybrids between the two species. In the present study, somatic cell hybrid gene mapping methodologies9 have been used to determine the chromosome localization10 of the human insulin gene. Human–mouse cell hybrids with different numbers and combinations of human chromosomes were examined for the presence of specific human chromosomes and the human insulin gene using cloned human and rat cDNA probes. A 14-kilobase DNA fragment containing the human insulin gene was present in some cell hybrids and was easily distinguished from the DNA fragments containing the mouse insulin gene found in all cell hybrids. Co-existence of the 14-kilobase fragment and chromosome 11 indicate that the insulin gene resolves on chromosome 11 in humans. Continue reading >>

Gene Therapy And Genetic Engineering

Gene Therapy And Genetic Engineering

For bacteria to make insulin, where do they get the insulin gene to insert into the bacteria? -A graduate student from California Back in the 1970's scientists managed to coax bacteria into making the insulin that many people need to treat their diabetes. They did this by putting the human insulin gene into the bacteria. The insulin gene they used came from human DNA. The scientists were able to get this gene in a couple of different ways. Neither of which was very easy back in the 70's! One group managed to make it on a machine called a DNA synthesizer. Like its name sounds, this machine makes DNA. Luckily the insulin gene is small since these machines could only make small snippets of DNA. A second group managed to fish it out of human DNA. This was done by putting random pieces of human DNA into bacteria and finding the bacterium that had the insulin gene. This is really hard to do but used to be the only way to get big pieces of DNA. Nowadays, what with the human genome project, it'd be much easier. By knowing just a bit about the gene they're interested in, scientists can just go look it up on the computer. Then they can simply pluck the DNA they're interested in right out of a tube of human DNA. Of course getting the gene isn't enough. You also need to get it into bacteria and have the bacteria be able to read the gene. Then you need to purify the insulin away from the bacteria. Luckily you only asked about the first part so I'll focus on that. What I thought I'd do is go over how scientists originally got the insulin gene. Then we'll look at what they might do now in a similar situation. But first, we're going to need to go into a little background. We need to go over what genes and proteins are and how they're related. Only then will we see how scientists were a Continue reading >>

Insulin Gene Expression Is Regulated By Dna Methylation

Insulin Gene Expression Is Regulated By Dna Methylation

Abstract Insulin is a critical component of metabolic control, and as such, insulin gene expression has been the focus of extensive study. DNA sequences that regulate transcription of the insulin gene and the majority of regulatory factors have already been identified. However, only recently have other components of insulin gene expression been investigated, and in this study we examine the role of DNA methylation in the regulation of mouse and human insulin gene expression. Methodology/Principal Findings Genomic DNA samples from several tissues were bisulfite-treated and sequenced which revealed that cytosine-guanosine dinucleotide (CpG) sites in both the mouse Ins2 and human INS promoters are uniquely demethylated in insulin-producing pancreatic beta cells. Methylation of these CpG sites suppressed insulin promoter-driven reporter gene activity by almost 90% and specific methylation of the CpG site in the cAMP responsive element (CRE) in the promoter alone suppressed insulin promoter activity by 50%. Methylation did not directly inhibit factor binding to the CRE in vitro, but inhibited ATF2 and CREB binding in vivo and conversely increased the binding of methyl CpG binding protein 2 (MeCP2). Examination of the Ins2 gene in mouse embryonic stem cell cultures revealed that it is fully methylated and becomes demethylated as the cells differentiate into insulin-expressing cells in vitro. Figures Citation: Kuroda A, Rauch TA, Todorov I, Ku HT, Al-Abdullah IH, Kandeel F, et al. (2009) Insulin Gene Expression Is Regulated by DNA Methylation. PLoS ONE 4(9): e6953. Editor: Kathrin Maedler, University of Bremen, Germany Received: April 13, 2009; Accepted: August 5, 2009; Published: September 9, 2009 Copyright: © 2009 Kuroda et al. This is an open-access article distributed und Continue reading >>

Insulin Gene

Insulin Gene

The polypeptide hormone insulin is required for normal glucose homeostasis. Lack of insulin or insulin insufficiency leads to diabetes that affects up to 5% of the human population. Gene location Insulin is formed as a precursor protein preproinsulin. This is coded by the INS gene. In some animals there are two insulin genes or two genes that code for insulin. In most animals, including humans, a single gene is present. The hypothesis of a single gene is enhanced by the genetic studies of inheritance of defects in the insulin gene. In addition, there seems to be no sex-predilection while inheriting defects in the insulin gene. This means that the gene coding for insulin does not lie in the sex chromosomes (XX for females and XY for males) but in the autosomes (the 20 pairs of chromosomes barring the one pair of sex chromosomes). The insulin gene has been recently uncoded in its complete form in genomic studies. Human and rat insulin genes have been cloned and the DNA has been sequenced. It was seen that mouse and rat insulins are identical and they have similar gene sequences and organization. Similarities in genetic sequences in human have been found as well. Studies reveal that the 14-kilobase fragment that codes for insulin lies on the chromosome 11 in humans. Gene stimulation and inhibition The insulin gene is expressed almost exclusively in pancreatic β-cells. Glucose in blood is the major stimulant that regulates the insulin gene expression and enables the beta cells to produce insulin and maintain an adequate store of intracellular insulin to sustain the secretory demand. Glucose in blood acts via transcription factors like pancreatic/duodenal homeobox-1 (PDX-1, mammalian homologue of avian MafA/L-Maf (MafA), Beta2/Neuro D (B2)), and controls the rate of transcr Continue reading >>

Global Haplotype Diversity In The Human Insulin Gene Region

Global Haplotype Diversity In The Human Insulin Gene Region

Global Haplotype Diversity in the Human Insulin Gene Region 1 Department of Genetics, University of Leicester, Leicester LE1 7RH, UK 2 McDonald Institute for Archaeological Research, University of Cambridge, Cambridge CB2 3ER, UK The insulin minisatellite (INS VNTR) has been intensively analyzed due to its associations with diseases including diabetes. We have previously used patterns of variant repeat distribution in the minisatellite to demonstrate that genetic diversity is unusually great in Africans compared to non-Africans. Here we analyzed variation at 56 single nucleotide polymorphisms (SNPs) flanking the minisatellite in individuals from six populations, and we show that over 40% of the total genetic variance near the minisatellite is due to differences between Africans and non-Africans, far higher than seen in most genomic regions and consistent with differential selection acting on the insulin gene region, most likely in the non-African ancestral population. Linkage disequilibrium was lower in African populations, with evidence of clustering of historical recombination events. Analysis of haplotypes from the relatively nonrecombining region around the minisatellite revealed a star-shaped phylogeny with lineages radiating from an ancestral African-specific haplotype. These haplotypes confirmed that minisatellite lineages defined by variant repeat distributions are monophyletic in origin. These analyses provide a framework for a cladistic approach to future disease association studies of the insulin region within both African and non-African populations, and they identify SNPs which can be rapidly analyzed as surrogate markers for minisatellite lineage. The insulin minisatellite, located within the promoter of the human insulin gene, has been intensely investig Continue reading >>

Omim Entry - * 176730 - Insulin; Ins

Omim Entry - * 176730 - Insulin; Ins

Insulin, synthesized by the beta cells of the islets of Langerhans, consists of 2 dissimilar polypeptide chains, A and B, which are linked by 2 disulfide bonds. However, unlike many other proteins, e.g., hemoglobin, made up of structurally distinct subunits, insulin is under the control of a single genetic locus; chains A and B are derived from a 1-chain precursor, proinsulin, which was discovered by Steiner and Oyer (1967). Proinsulin is converted to insulin by the enzymatic removal of a segment that connects the amino end of the A chain to the carboxyl end of the B chain. This segment is called the C (for 'connecting') peptide. The human insulin gene contains 3 exons; exon 2 encodes the signal peptide, the B chain, and part of the C-peptide, while exon 3 encodes the remainder of the C-peptide and the A chain (Steiner and Oyer, 1967). The rat, mouse, and at least 3 fish species have 2 insulin genes (Lomedico et al., 1979). The single human insulin gene corresponds to rat gene II; each has 2 introns at corresponding positions. Deltour et al. (1993) showed that in the mouse embryo the 2 proinsulin genes are regulated independently, at least in part. The existence of a single insulin gene in man is supported by the findings in patients with mutations. The greatest variation among species is in the C-peptide. Receptor binding parts have been highly conserved. Some of these sites are involved with insulin-like activity, some with growth-factor activity, and some with both. INS-IGF2 Spliced Read-Through Transcripts By EST database analysis and RT-PCR, Monk et al. (2006) identified 2 read-through transcripts, which they called the INSIGF long and short isoforms, that contain exons from both the INS gene and the downstream IGF2 gene (147470). The INSIGF short isoform contains Continue reading >>

Genetic Engineering

Genetic Engineering

Genetic engineering involves the extraction of a gene from one living organism and inserting it into another organism, so that the receiving organism can express the product of the gene. A basic technique used is the genetic engineering of bacteria. It can be broken into the following key stages: Selection of characteristics. Identifying the gene from amongst all the others in the DNA of the donor organism. Isolation of the gene. Obtaining a copy of the required gene from the DNA of the donor organism and placing it in a vector. (A vector in biology refers to an organism that acts as a vehicle to transfer genetic material from a donor organism to a target cell in a recipient organism.) Insertion Use the vector to introduce the gene into the host cell. Replication Allow the host cell to multiply to make multiple clones of the genes. Example of Genetically Engineered Bacteria – Production of Human Insulin An example of genetically engineered bacteria is in the production of human insulin. Insulin is a protein hormone produced in the pancreas which has an important function in the regulation of blood sugar levels. Insulin facilitates the transport of glucose into cells. A deficiency in insulin is one of the causes of the disease diabetes mellitus or sugar diabetes in which the sugar levels in the blood become raised resulting in harmful consequences. At least 3% of the world’s population is affected by diabetes mellitus and sufferers of the disease require insulin injections to manage the disease. Pure Mouse Isotype Controls - IgG subclasses, IgA, IgM, IgE. Ad ICL - A trusted producer of high quality antibodies since 1977. icllab.com Learn more Before genetic engineering, insulin used for treatment was sourced from the pancreas of slaughtered pigs and cattle. This sour Continue reading >>

What Is Genetic Engineering?

What Is Genetic Engineering?

Genetic engineering refers to the direct manipulation of DNA to alter an organism’s characteristics (phenotype) in a particular way. What is genetic engineering? Genetic engineering, sometimes called genetic modification, is the process of altering the DNA? in an organism’s genome?. This may mean changing one base pair? (A-T or C-G), deleting a whole region of DNA, or introducing an additional copy of a gene?. It may also mean extracting DNA from another organism’s genome and combining it with the DNA of that individual. Genetic engineering is used by scientists to enhance or modify the characteristics of an individual organism. For example, genetic engineering can be used to produce plants that have a higher nutritional value or can tolerate exposure to herbicides. How does genetic engineering work? To help explain the process of genetic engineering we have taken the example of insulin, a protein? that helps regulate the sugar levels in our blood. Normally insulin? is produced in the pancreas?, but in people with type 1 diabetes? there is a problem with insulin production. People with diabetes therefore have to inject insulin to control their blood sugar levels. Genetic engineering has been used to produce a type of insulin, very similar to our own, from yeast and bacteria? like E. coli?. This genetically modified insulin, ‘Humulin’ was licensed for human use in 1982. The genetic engineering process A small section is then cut out of the circular plasmid by restriction enzymes, ‘molecular scissors’. The gene for human insulin is inserted into the gap in the plasmid. This plasmid is now genetically modified. The genetically modified plasmid is introduced into a new bacteria or yeast cell. This cell then divides rapidly and starts making insulin. To create Continue reading >>

Insulin

Insulin

This article is about the insulin protein. For uses of insulin in treating diabetes, see insulin (medication). Not to be confused with Inulin. Insulin (from Latin insula, island) is a peptide hormone produced by beta cells of the pancreatic islets, and it is considered to be the main anabolic hormone of the body.[5] It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of, especially, glucose from the blood into fat, liver and skeletal muscle cells.[6] In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or, in the case of the liver, into both.[6] Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood.[7] Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is therefore an anabolic hormone, promoting the conversion of small molecules in the blood into large molecules inside the cells. Low insulin levels in the blood have the opposite effect by promoting widespread catabolism, especially of reserve body fat. Beta cells are sensitive to glucose concentrations, also known as blood sugar levels. When the glucose level is high, the beta cells secrete insulin into the blood; when glucose levels are low, secretion of insulin is inhibited.[8] Their neighboring alpha cells, by taking their cues from the beta cells,[8] secrete glucagon into the blood in the opposite manner: increased secretion when blood glucose is low, and decreased secretion when glucose concentrations are high.[6][8] Glucagon, through stimulating the liver to release glucose by glycogenolysis and gluconeogenesis, has the opposite effect of insulin.[6][8] The secretion of insulin and glucagon into the Continue reading >>

More in insulin