The short version of prothymosin alpha fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-06-26 and is reviewed periodically as new material appears.
Thymosin alpha 1 was identified in 1977 as a component of thymosin fraction 5, a heterogeneous preparation used in early studies of thymic function. Investigators purified the active material and determined its amino acid sequence, which enabled chemical synthesis. Work in the following decades concentrated on T-cell maturation and immune reconstitution in animals and small human cohorts. Early preparations varied in composition, so results from that period are difficult to compare with studies using defined synthetic peptide.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Findings across trials are mixed; some report changes in selected immune markers, while others find no clear clinical benefit. Many studies are small and define outcomes differently, which limits comparison. Regulatory approval is confined to a few countries, and the compound is not an approved drug in the United States or most of Europe.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids whose sequence matches the amino-terminal region of prothymosin alpha. The chain is acetylated at its first residue and contains one disulfide bridge between two cysteine residues, which folds the molecule into a compact loop. Its molecular formula, C129H215N33O55, corresponds to a monoisotopic mass of roughly 3,106 daltons. Material used in laboratories is made by solid-phase synthesis rather than isolated from animal tissue.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
| Property | Value | Notes |
|---|---|---|
| First described | 1977 | Reported as a component of thymosin fraction 5 |
| Sequence length | 28 amino acids | N-terminal residue is acetylated |
| Net charge at neutral pH | Negative | Reflects a high proportion of acidic residues |
| Principal studied uses | Chronic hepatitis B and vaccine adjuvant | Research uses outnumber approved indications |
| Regulatory status | Approved in a limited number of countries | Not approved in the United States or most of Europe |
Thymosin alpha 1 is a short peptide of 28 amino acid residues that derives from the amino terminal region of a larger precursor protein known as prothymosin alpha. The peptide carries an acetyl group on its first residue and contains no disulfide bonds or carbohydrate chains. Its sequence is highly conserved across mammalian species, which is one reason laboratories treat it as a molecule with a defined and reproducible structure rather than a variable tissue extract. The name follows an early naming convention for thymus-derived fractions and does not imply that the peptide acts as a hormone in the classical endocrine sense.
Biologically, the peptide is studied mainly in the context of immune cell development and regulation. It is produced in the thymus and in several other tissues, and it appears to influence the maturation and activity of T cells and other immune populations. Laboratory work describes effects on cytokine production, on the balance between T cell subsets, and on the function of dendritic cells. Much of this evidence comes from cell culture and animal models, so the extent to which the same pathways operate in humans remains an open question.
Lyophilized material is typically treated as a hygroscopic solid that should be brought to room temperature before the container is opened, which limits condensation on the powder. Reconstitution is commonly done with sterile water or a buffered diluent, and gentle mixing is preferred over vigorous agitation to reduce foaming and surface adsorption. Because peptides can bind to plastic and glass, diluents containing a small amount of carrier protein are sometimes used in laboratory work. Working solutions are generally aliquoted and prepared fresh rather than subjected to repeated freezing and thawing.
Stability depends on temperature, pH, and the number of freeze-thaw events the sample has experienced. Freeze-dried material is commonly held at -20 °C or colder, while reconstituted liquid is kept cold and used within a short window. Extreme pH and prolonged light exposure can promote deamidation, oxidation, or aggregation, particularly at asparagine and methionine positions. Adsorption to container walls can lower the measured concentration of a dilute solution even when the peptide molecules themselves remain intact.
=== Calcium ion channels === Calcium channels are important for certain cell-signaling cascades as well as neurotransmitter release at axon terminals. A variety of different types of calcium ion channels are found in excitable cells. As with sodium ion channels, calcium ion channels have been isolated and cloned by chromatographic purification techniques. It is notable, as with the case of neurotransmitter release, that calcium channels can interact with intracellular proteins and plays a strong role in signaling, especially in locations such as the sarcoplasmic reticulum of muscle cells.
Shulman proposed that lipid-induced insulin resistance results from the accumulation of sn-1,2-diacylglycerol (DAG) in the plasma membrane, which activates novel protein kinase C (nPKC) isoforms—PKCθ in skeletal muscle and PKCε in liver and white adipose tissue—impairing insulin signaling. Shulman's lab explored interventions such as weight loss, thiazolidinediones, adiponectin, leptin, and liver-targeted mitochondrial protonophores to reverse insulin resistance by lowering plasma membrane DAG and inhibiting the nPKC pathway. He also pioneered 13C and 31P NMR methods to measure ATP synthesis and mitochondrial oxidation in vivo. His team identified age-related declines in mitochondrial fat oxidation linked to insulin resistance in elderly individuals, and in insulin-resistant offspring of people with T2D. They showed that chronic AMPK activation drives mitochondrial biogenesis via increased expression of PGC-1α. Shulman used 13C NMR to quantify rates of hepatic glycogenolysis and gluconeogenesis, showing that the latter accounts for over half of fasting hepatic glucose production following an overnight fast overturning the Cahill hypothesis that hepatic glycogenolysis accounts for >90% of glucose production in humans following an overnight fast.
=== Magazine === OECD Observer, an award-winning magazine, was launched in 1962. The magazine appeared six times a year until 2010, and became quarterly in 2011 with the introduction of the OECD Yearbook, launched for the 50th anniversary of the organisation. The online and mobile editions contained news, analysis, reviews, commentaries and data on global economic, social and environmental challenges and listings of the latest OECD books. An OECD Observer Crossword was introduced in Q2 2013. The OECD Observer was last issued in the fourth quarter of 2019, with a double edition looking ahead at artificial intelligence, and a cover leading on why statistical offices should hire a comedian. The OECD Observer website closed in the first quarter of 2021; the archive can be consulted at www.oecd.org.
Sources: en.wikipedia.org
A sequence-controlled polymer is a macromolecule, in which the sequence of monomers is controlled to some degree. This control can be absolute but not necessarily. In other words, a sequence-controlled polymer can be uniform (its dispersity Ð is equal to 1) or non-uniform (Ð>1). For example, an alternating copolymer synthesized by radical polymerization is a sequence-controlled polymer, even if it is also a non-uniform polymer, in which chains have different chain-lengths and slightly different compositions. A biopolymer (for example a protein) with a perfectly defined primary structure is also a sequence-controlled polymer. However, in the case of uniform macromolecules, the term sequence-defined polymer can also be used. With comparison to traditional polymers, the composition of sequence-controlled polymers can be precisely defined via chemical synthetic methods, such as multicomponent reactions, click reactions etc. Such tunable polymerizing manner endows sequence-controlled polymers with particular properties and thereby, sequence-controlled polymers-based applications (e.g. information storage, biomaterials, nanomaterials etc.) are developed. In nature, DNA, RNA, proteins and other macromolecules can also be recognized as sequence-controlled polymers for their well-ordered structural skeletons. DNA, based on A-T, C-G base pairs, are formed in well-aligned sequences. Through precise sequences of DNA, 20 amino acids are able to generate sequential peptide chains with three-dimensional structures by virtue of transcription and translation process.
== Function == This gene encodes one of the three alpha chains of type VI collagen, a beaded filament collagen found in most connective tissues. The product of this gene contains several domains similar to von Willebrand factor type A domains. These domains have been shown to bind extracellular matrix proteins, an interaction that explains the importance of this collagen in organizing matrix components. Pathogenic variants in this gene are associated with collagen VI-related dystrophies, a spectrum of disorders that includes Bethlem muscular dystrophy, intermediate collagen VI-related dystrophy, and Ullrich congenital muscular dystrophy. Certain biallelic COL6A2 variants have also been associated with a phenotype referred to as myosclerosis. Three transcript variants have been identified for this gene.
Sinosauropteryx (meaning "Chinese reptilian wing") is an extinct genus of coelurosaurian theropod dinosaurs. Described in 1996, it was the first dinosaur taxon outside of Avialae (birds and their immediate relatives) to be found with evidence of feathers. It was covered with a coat of very simple filament-like feathers. Structures that indicate the colour pattern have also been preserved in some of its feathers, which show that Sinosauropteryx had a countershading pattern in its body with a banded tail. The reddish brown colouration previously inferred for Sinosauropteryx is based on the melanosomes preserved in the specimen of a separate genus, Huadanosaurus. Some contention has arisen with an alternative interpretation of the filamentous impression as remains of collagen fibres, but this has not been widely accepted. Sinosauropteryx was a small theropod with an unusually long tail and short arms. The longest known specimen reaches up to 1.07 metres (3.51 feet) in length, with an estimated weight of 0.55 kilograms (1.21 pounds). It was considered a close relative of the similar but older genus Compsognathus, with both genera belonging to the family Compsognathidae, though subsequent analyses did not recover this family to be monophyletic and placed Sinosauropteryx within its own family, Sinosauropterygidae. Two species of Sinosauropteryx have been named. The first, S. prima, is known from three specimens, named "first" in reference to its status as the first feathered non-avian dinosaur species discovered.
Sources: en.wikipedia.org
Bimagrumab (BYM338) is a human monoclonal antibody first developed by Novartis and currently by Eli Lilly to treat pathological muscle loss and weakness. It binds to and inhibits activin receptor type-2B. Bimagrumab must be administered intravenously at a hospital or clinic. The medication has a long half-life and is administered once a month.
=== Category:EC 1.6 (act on NADH or NADPH) === Category:EC 1.6.1 (with NAD+ or NADP+ as acceptor) Category:EC 1.6.2 (with a cytochrome as acceptor) Category:EC 1.6.3 (with oxygen as acceptor) Category:EC 1.6.4 now Category:EC 1.8.1 Category:EC 1.6.5 (with a quinone or similar compound as acceptor) NADH dehydrogenase EC 1.6.5.3 Category:EC 1.6.6 (with a nitrogenous group as acceptor) Category:EC 1.6.7 now Category:EC 1.18.1 Category:EC 1.6.8 now Category:EC 1.5.1 Category:EC 1.6.99 (with other acceptors)
=== Flexible linkers === Turns are sometimes found within flexible linkers or loops connecting protein domains. Linker sequences vary in length and are typically rich in polar uncharged amino acids. Flexible linkers allow connecting domains to freely twist and rotate to recruit their binding partners via protein domain dynamics. They also allow their binding partners to induce larger scale conformational changes by long-range allostery.
Sources: en.wikipedia.org
Trials differ in patient population, dose schedule, background treatment, and the endpoints used to judge success. Many are small and single-center, so random variation can dominate the reported effects.
Authorization is limited to a small number of countries and covers specific indications such as chronic hepatitis B and vaccine adjuvant use. Availability and labelling differ by jurisdiction.
Most reviews describe it as an immunomodulatory agent with an uncertain clinical effect. They generally call for larger, better-controlled trials before firm conclusions are drawn.
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.