Scientists solve some puzzles of necrocytosis

Normally our tissues are healthy, but some of them will develop inflammation and disease. "What is it that causes inflammation? Is necroptosis the switch to inflammation? How does this process work?" said Manolis Pasparakis, professor of genetics at the University of Cologne, Germany. Professor Pasparakis' group of researchers published an article in the November 7 issue of Nature which also publishes other studies on recombinant horse proteins, partly answering these questions.

Professor Pasparakis' team constructed special skin cells: mice had RIPK1 lack in keratinocytes. The researchers had originally thought that the cells did not develop procedural necrosis due to RIPK1 deficiency, but the researchers got the opposite result: the cells keratinocytes in mice showed necrosis and died, triggering skin inflammation. By further analysis, the researchers found the answer. Because RIPK1 will inhibit another procedural necrosis factor: ZBP1 protein, genetic removal of ZBP1 can inhibit the RIPK1 deletion caused by necrocytosis and inflammation.

"We know that ZBP1 is a DNA-sensing protein that is involved in fighting the immune system of certain viruses but has yet to find its role in inflammation," said Chun Kim, co-author of the paper. So how does RIPK1 suppress ZBP1?

To answer this question, the researchers used the CRISPR gene editor to modify three amino acids in the RHIM domain, a key structure for the interaction of RIPK1 with two other proteins that regulate necrocytosis. Mice that express this mutated RIPK1 in all cells will not survive after birth. But only in the expression of keratinocytes will just lead to skin inflammation.

The researchers found that when RIPK1 PHIM domain shows mutations, ZBP1 will open necrocytosis, leading to perinatal mortality and adult skin inflammation. "This surprising result is that the three amino acids of RIPK1 can prevent ZBP1-induced necrosis, and it is the key to survival of mice and prevention of skin inflammation," said Juan Lin, one of the authors.

"We solved some of the puzzles, but there are bigger puzzles still unclear," Pasparakis said. "ZBP1 acts as a viral sensor, and now our study associates it with inflammation and death." In most cases, chronic inflammation in the human body is still a mystery. Why do some cases of inflammation in the human body happen? Our study found the important role of ZBP1. Now we wonder whether the virus or bacteria can activate ZBP1. The next step researchers will explore the further association of ZBP1 and inflammation in the human body. Flarebio provides you with good-quality recombinant proteins including recombinant ECEL1.

Keratins are endogenous ligands of DEC205

In November 7, 2016, the United States Academy of Sciences (PNAS) published a research result titled “Keratin mediates the recognition of apoptotic and necrotic cells through dendritic cell receptor DEC205/CD205” online and it was completed by He Yongning research group at the Chinese Academy of Sciences Shanghai Institute of life science biochemistry and cell biology Institute using recombinant human proteins, which discloses the molecular mechanism of immunoreceptor DEC205 / CD205 recognizing dead cells by binding to cytokeratin.

A large number of cells die in the human body every day. The identification of dead cells and clean-up is indispensable to maintain the body's homeostasis and avoid autoimmune diseases and is also an important function of the immune system. It is usually completed by dendritic cells, macrophages and other phagocytic cells. Phagocytic cells need to recognize dead cells through their surface receptor molecules. DEC205 (CD205) is one of the main markers and endocytotic receptors of dendritic cells and is widely used in immunotherapy. But its function is very limited understanding. Since the receptor was found in 1995, the cell ligand has not been found. In a previous study, the team found that the extracellular portion of DEC205 exhibited different conformations under acidic and basic conditions and that this conformational change was directly related to its function. DEC205 specifically recognizes apoptotic necrotic cells only under acidic conditions, thus revealing its physiological function as a dying cell receptor (PNAS, 2015). However, how DEC205 recognizes dead cells is still unclear.

In this work, on the basis of previous results, Cao Longxing and other researchers looked for human DEC205 on the cell ligands through a series of biochemical and biophysical experiments. As a result, it was found that keratins are endogenous ligands of DEC205. Further experiments have shown that the human DEC205 molecule can specifically recognize the C-terminal domain of keratin by its N-terminal domain under acidic conditions. Keratin is an important component of the cytoskeleton and usually can form fibrous intermediate filaments involved in the maintenance of cell morphology and mechanical properties, but other physiological role of keratin is not very clear. This work shows that keratin not only plays an important role in maintaining the cell and tissue structure, but also as a marker of cell death and is recognized by the immune system and mediates an acid-base-dependent death cell recognition pathway. In addition, keratin and tumor also exist between the close contact and is used for clinical diagnosis of a variety of tumors. Therefore, the finding of DEC205 as a keratin receptor provides a new way of thinking for diagnosis and treatment of cancer and related diseases. Flarebio offers good-quality recombinant proteins such as recombinant ITGB5 at competitive prices.

Scientists discover an antimicrobial peptide to destroy drug-resistant bacteria

In order to deal with the arsenal of bacteria, scientists have taken various different approaches. They no longer develop and improve traditional antibiotics but look to some of the natural antimicrobial substances through recombinant dog proteins. Some of them are fragments of proteins, known as peptide. Recently, researchers from the Massachusetts Institute of Technology, University of Brasilia and the University of British Columbia in Canada designed an antimicrobial peptide that can eliminate many bacteria, including drug-resistant bacteria. This result was published in the Nature Publishing Group Scientific Reports.

Many organisms naturally produce antimicrobial peptides, which are part of the body's own immune system, not only to destroy invading bacteria, but also kill other microorganisms, including fungi and viruses. They have the advantage of acting on bacteria through a number of different mechanisms. First, they can drill holes in the cell membrane that invades the bacteria and can destroy multiple targets, including DNA, RNA, and proteins when inside the bacteria. Second, they can activate the body's own immune system and call the white blood cells to completely eradicate the invasion of microorganisms. This is also the biggest difference between these peptides and traditional antibiotics. In addition, they can also inhibit the immune system due to excessive systemic sepsis.

Naturally-produced antimicrobial peptides are usually composed of 20 amino acids, which include a positively-charged region to help punch in the cell membrane and a hydrophobic region so that it can smoothly go through the cell membrane into the bacteria inside. With the development of modern computing technology, scientists can replace or add new amino acids to transform the natural antibacterial peptides and even design and manufacture of new antibacterial peptides so that they become more lethal.

In this study, the scientists improved based on antibacterial peptide clavanin-A found in the body of a marine organism sea squirt, including the addition of five hydrophobic amino acids to make the entire polypeptide more easily to go into the bacteria. They called the new antibacterial peptides clavanin-MO. In mice, clavanin-MO was found to abolish resistant E. coli and Staphylococcus aureus strains. It also destroys biofilms formed by bacteria on the surface of objects, such as biofilm formed by Pseudomonas aeruginosa found in the lungs of patients with cystic fibrosis.

"Our goal is to find solutions to antibiotic resistance," said Cesar de la Fuente, Ph.D., one of the authors of the paper. Drug-resistant bacteria are expected to exceed cancer and become the number one killer of human health. Antibacterial polypeptide provides an effective alternative: a molecule that can kill resistant bacteria and boost immunity and prevent excessive immune responses."

The researchers plan to further improve the design of antibacterial peptides and eventually put into clinical use. They believe that if combined with traditional antibiotics, it can be more effective in the eradication of bacteria and prevent new drug resistance. Flarebio offers good-quality recombinant proteins like recombinant CDH11.

The key genetic switch in the liver has the function of regulating glucose metabolism

Researchers have recently discovered that the key genetic switch in the liver has the function of regulating glucose metabolism and insulin secretion in other organs through recombinant mouse proteins.

Diabetes is a chronic disease. Now, the incidence of diabetes is becoming more and more serious. In Germany, more than 6 million people suffer from this disease. Diabetes is characterized by impaired glucose metabolism (with the exception of type 1 diabetes) as well as by the body's response to insulin. Scientists are currently looking for possible causes of the disease and modulators that could be used to intervene therapeutically.

Currently, a team led by Professor Stephen Herzig has discovered a new mechanism responsible for mediating glucose metabolism. Transforming growth factor-β1-stimulated clone 22D4 (abbreviated as TSC22D4) acts as a molecular switch in the liver and regulates the effects on the systemic metabolic genes.

“As early as 2013, researchers have shown that increasing the expression of TSC22D4 in the liver of cancer mice can lead to severe weight loss,” study leader Herzig said. In this study, researchers have studied the role of this gene modulator in diabetes.

In the current study, the researchers found that TSC22D4 inactivation can improve insulin resistance and glucose metabolism. Further study showed that TSC22D4 can inhibit the formation of apolipoprotein 13. This protein can be released as a messenger material from the liver and regulate other organs of glucose metabolism.

In order to examine the new mechanism and clinical relevance of this finding, the researchers examined 66 patients with type 2 diabetes or healthy liver. The results showed that in the liver of diabetic patients, TSC22D4 gene expression was more than normal, and the synthesis of corresponding reduction in apolipoprotein 13 reduced. "The results of the study help to find new ways to treat diabetes," the researchers said. Flarebio offers recombinant proteins such as recombinant CDH11 at competitive prices.

A new immunotherapy technology that can completely reverse allergic reaction in mice

In the best of cases, food allergy can only be frustrating; while in the worst case, food allergy can be life-threatening. Recently, however, scientists have developed a new immunotherapy technology that can completely reverse the allergic reaction in mice and the research used a lot of recombinant proteins including recombinant rat proteins. They believe that this technology can also be used for the treatment of human allergies. This treatment technique works by triggering the body to produce new dendritic cells that can tell other immune systems to stop the excessive immune response. This ensures that the quickest and most severe types of allergic reactions will not occur.

"If we can use this new therapy to reliably treat food allergies or related diseases such as asthma or autoimmune diseases (such as multiple sclerosis)," says John Gordon, a scientist at the University of Saskatchewan in Canada, then it will change the lives of many affected people."

Dendritic cells are naturally generated in tissues exposed to the environment, such as the lining of the skin or nasal cavity, lungs, stomach and intestine. Gordon and his team extracted the cells from mice and exposed them to a specific mixture of proteins, a naturally occurring vitamin A-related acid in the human digestive system, and an allergen (peanut or egg white).

When these modified dendritic cells were re-implanted in mice, the allergic reaction in mice almost disappeared, and the sensitive immune cells activated by allergic substances have been like in healthy and non-allergic the human body. Although the technology has currently been tested only in mice, the researchers hoped to be able to carry out human trials next year. "We have a lot of people with allergies who are willing to give their cells to us for testing," Gordon said.

The effective treatment of allergies can change the lives of millions of people. In the United States alone, there are an estimated 15 million food allergy sufferers, and one in 13 children suffers from some kind of allergy. The team believes the study could also be used for other diseases associated with the immune system such as multiple sclerosis (MS). Gordon explained that only a few changes can be applied to the treatment of autoimmune diseases.

The study was published in the Journal of Allergy and Clinical Immunology. Flarebio provides you with superior recombinant proteins including recombinant CDH2.

A study shows new method of inhibiting cancer genes

Researchers at the University of Illinois at Chicago have discovered a new way to stop the mutations in nearly 30% of cancer patients through recombinant human proteins. Gene mutations in the RAS family of proteins are present in nearly 90% of pancreatic cancer patients and are also prevalent in patients with colon, lung and melanoma (the most dangerous skin cancer). The histone consists of three members: K-RAS, H-RAS and N-RAS.

The prevalence of RAS mutations in human cancers and the dependence of RAS on tumor survival make RAS a major target for cancer research and drug discovery. Scientists and drug developers have long sought RAS oncogene to find a new way to treat cancer, but they have yet to find a drug that can safely inhibit the activity of oncogenes.

A team led by John O'Bryan, an associate professor of pharmacology at the University of Chicago School of Medicine, took a different approach to RAS and found that a synthetic binding protein called NS1 monobody which they synthesized in the laboratory can block the activity of RAS protein.

"We did not find a drug or a specific inhibitor," says O'Bryan, a member of the University of Illinois Cancer Center, who met at the Jesse Brown VA Medical Center in Chicago, "We use monoclonal antibody technology, a protein engineering technique, to identify regions of RAS that are critical to its function. Unlike traditional antibodies, which do not rely on their environment and can easily be used as inhibitors of gene coding Agent."

"The beauty of this technique is that when a mAb binds to a protein, it's usually acting as an inhibitor of the protein," he said. The monoclonal antibody was developed by Shohei Koide, a professor of biochemistry and molecular pharmacology at New York University and co-author of the study. They are used for different proteins, including enzymes and receptors.

The researchers found that NS1 monobody binds to a region of the RAS protein molecule that is not previously thought to be important for carcinogenic activity. NS1 strongly inhibits carcinogenic K-RAS and H-RAS by blocking the ability of the protein to interact with another identical protein to form a molecule. NS1 does not affect gene N-RAS.

O'Bryan said these findings of biology and chemistry published in The Wall Street Journal provides important insight into the long-standing problem of RAS protein function in cells. These insights can help to guide the development of new methods of treating cancer by interfering with cancer cell mutations in RAS function.

"Developing an effective RAS inhibitor represents a holy grail in cancer biology," O'Bryan said. "We now have a powerful tool that we can use to further investigate RAS functions. Although these findings will require much research and effort to be used outside of the laboratory, this study provides new insights on how RAS slows down tumor growth." Flarebio offers recombinant proteins of good quality like recombinant Phex.

How do plant seeds fool beetles?

We have seen many animals survive by being camouflaged to avoid being eaten by their predators. But have you seen any plants protect themselves by mimicry? A team consisted of researchers from both University of Cape Town and the University of KwaZulu-Natal in South Africa, has found an example of that - a seed from a plant uses mimicry to fool a beetle. They published their paper in the journal Nature Plants, which also have other studies on recombinant rat proteins. In their paper they describe the relationship between the seeds and the beetles and the deceptive dispersal they witnessed through observation.

In fact, many examples of animals or plant mimicry have been noted and reported in studies published before, but until now, no examples of a plant using mimicry to disperse seeds have been documented. The research which seeds of a grassy plant known as Ceratocaryum argenteum were somehow dispersed used to draw public attention, but no one had figured out how it was occurring. The researchers write that they believed it was because mice carried them about. To make sure about the guess, they dropped 195 of the seeds near monitoring stations in De Hoop Nature Reserve and recorded what happened with video cameras.

Over a single day, dung beetles moving through the area had grabbed nearly half of the seeds and rolled them to nearby locations where they buried them later. As you know, dung beetles normally grab animal droppings and bury them for eating or use them for a place to lay eggs.

Subsequently, the researchers dug up all the seeds which were buried by the beetles and found no traces of beetles around, let alone any eggs laid by dung beetles. The results suggested that those beetles discovered the ruse as they attempted to eat them or lay eggs. Therefore, the team guessed that the dung beetles had been fooled into carrying the seeds to a distant places and planting them and got no reward for their efforts.

They inspected the seeds and found that they looked like bontebok dung a lot. What's more, the chemical composition of the seeds closely resembled dung as well. It must be the smell of the seeds that fools the beetles. Flarebio provides you with superior recombinant proteins including recombinant Cd44 at competitive prices.