GRF(1-29) raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
Peptide degradation proceeds mainly through hydrolysis, oxidation of methionine, and deamidation of asparagine or glutamine residues. The maleimide group on the albumin-binding variant can also react with thiols or hydrolyze in aqueous media. Because these pathways accelerate with temperature and pH extremes, handling conditions strongly influence measured stability. Stability data in the public literature are limited and often generated under differing conditions, so general statements about shelf life should be read as approximate.
Research material is normally supplied as a freeze-dried powder in sealed vials. In that state the peptide is comparatively robust, but prolonged exposure to warmth, moisture, or light accelerates degradation. Storage at minus twenty degrees Celsius or lower, with desiccant and protection from light, is the commonly described practice. Vials should be allowed to reach room temperature before opening to limit condensation on the powder. Moisture uptake during handling is a recognized source of variability in later measurements.
Reconstitution is typically performed with sterile water or bacteriostatic water, added slowly against the vial wall. The resulting solution should be clear and colorless; cloudiness or visible particles suggest a problem with the material or the diluent. Once in solution, the peptide is less stable than the dry powder. Refrigerated storage at two to eight degrees Celsius is common for short-term holding, while freezing aliquots is described for longer periods.
Two related forms circulate in technical discussion under the same family name. The original version carries a drug affinity complex (DAC) that binds covalently to serum albumin after administration, and this linkage substantially extends circulation time. A second form, frequently written as modified GRF(1-29) or CJC-1295 without DAC, lacks that linker and clears much faster. The naming is a frequent source of confusion because the shorthand CJC-1295 can refer to either form depending on the source. Reports sometimes fail to specify which variant was studied.
The peptide backbone includes a D-alanine at position two, which resists cleavage by dipeptidyl peptidase IV, and several other substitutions that reduce degradation. Its molecular weight is roughly 3.4 kDa without the linker and about 3.6 kDa with it. The molecule is water soluble and is normally supplied as a lyophilized powder. Precise sequence and mass values depend on which variant is described, so technical documents usually state the exact form being referenced.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white lyophilized powder | Visual descriptor; not a measure of purity |
| Solubility class | Freely soluble in water | Aqueous dissolution may require gentle mixing |
| Typical storage (powder) | −20 °C or below, desiccated | Protect from light and ambient moisture |
| Typical storage (solution) | 2–8 °C, short term | Freeze aliquots where longer holding is needed |
| Purity assessment | Reversed-phase HPLC, area percent | Values depend on column, gradient, and detection wavelength |
CJC-1295 is a synthetic peptide modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. Its sequence corresponds to the first twenty-nine residues of human GHRH, with four substitutions that slow enzymatic breakdown. Early descriptions placed the compound in research on growth hormone deficiency and related conditions, and later literature groups it with the long-acting GHRH analogs. The name appears in both laboratory and popular fitness writing, where it sometimes labels chemically different peptides.
Two related peptides circulate under the CJC-1295 label, and they differ mainly in how long they persist in circulation. The version carrying a drug affinity complex includes a maleimidopropionic acid linker that forms a covalent bond with serum albumin. The other version, usually written as modified GRF(1-29) or tetrasubstituted GRF(1-29), lacks that linker and is cleared quickly. Mixing the two produces inconsistent readings of published half-life values, because the linker rather than the receptor-facing sequence drives most of the difference.
The core sequence keeps the receptor-binding region of GHRH while replacing four positions that are vulnerable to dipeptidyl peptidase-4 and other proteases. Substitutions at positions 2, 8, 15, and 27 raise metabolic stability relative to the natural hormone. The N-terminal residues remain essential for activity, so changes there generally lower potency. Molecular weight sits near 3368 daltons for the tetrasubstituted analog without the linker, while the albumin-binding form is heavier because of the added maleimide group.
CJC-1295 belongs to a family of synthetic peptides modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound is built from the first twenty-nine amino acids of the natural human sequence, a fragment that retains full receptor binding capacity. Native growth hormone-releasing hormone is degraded quickly in circulation, so the fragment alone has limited practical value. Early work therefore focused on chemical modifications that preserve receptor binding while slowing enzymatic breakdown. The result is a molecule described in the literature as a long-acting analog of the natural hormone.
Two forms circulate under the CJC-1295 name, and they differ by a single appended group. The version without a drug affinity complex carries four substitutions along the peptide chain, including a D-alanine near the amino terminus and replacements at three other positions. These changes block the enzyme dipeptidyl peptidase IV and remove a methionine residue that is prone to oxidation. The modified fragment is frequently labeled MOD GRF 1-29. Naming conventions are inconsistent across informal sources, which is a common source of confusion.
The dividing feature between the two forms is a maleimide-based drug affinity complex, abbreviated DAC. In the DAC-bearing version, a linker attaches the peptide to serum albumin after administration, and that association slows removal from plasma. The version lacking DAC appears in catalogs as MOD GRF(1-29) or tetrasubstituted GRF(1-29). Because informal writing treats both as one item, comparisons drawn from such sources routinely blend measurements taken from two molecules with substantially different behavior.
Four amino acid substitutions separate the modified backbone from the parent GRF(1-29) sequence. These changes reduce recognition by dipeptidyl peptidase IV and related proteases, extending the interval before degradation. Development work in this area sought longer-acting GHRH analogs for endocrine investigation. Published descriptions treat the substitution set as a defining property of the core sequence, while the albumin-binding linker is described separately as an optional addition to that same backbone.
=== No development reported === Adapalene/minocycline (FCD-105) – combination of adapalene (retinoid) and minocycline (tetracycline antibiotic) Auriclosene (AgaDerm; AgaNase; AL-46383A; CD-07223; DCDMT; NVC-422) – aganocide compound and antimicrobial Bermekimab (CA-18C3; CV-18C3; Hutruo; JNJ-77474462; MAB-p1; RA-18C3; T2-18C3; Xilonix) – monoclonal antibody against interleukin-1α BOS-356 (GSK-3008356) – diacylglycerol O-acyltransferase inhibitor Brilacidin (PMX-30063) – host defense protein (HDP) mimetic antibiotic Carbamide peroxide topical (E-0301) – disinfectant and bleaching agent CJM-112 – IL17A and IL17F inhibitor Clindamycin/tretinoin – combination of clindamycin (lincosamide antibiotic) and tretinoin (retinoid) Clindamycin/tretinoin – combination of clindamycin (lincosamide antibiotic) and tretinoin (retinoid) DMT-200 (DMT-210; DMT-220; SIG-990) – isoprenylcysteine analogue and various actions Estradiol valerate/dienogest (Climodien; Climodiène; Klimodien; Lafamme) – combination of estradiol valerate (estrogen) and dienogest (progestogen) Ethinylestradiol/chlormadinone acetate (Balianca; Belara; GRT4248) – combination of ethinylestradiol (estrogen) and chlormadinone acetate (progestogen) and a combined oral contraceptive Ethinylestradiol/drospirenone (Petibelle; SH-470; Yasmin; ZK-30595) – combination of ethinylestradiol (estrogen) and drospirenone (progestogen) GSK-1940029 – stearoyl-CoA desaturase inhibitor GT-20029 (AR-PROTAC) – androgen receptor degradation enhancer IP10-C8 – CD13 antigen inhibitor and dipeptidyl peptidase 4 (DPP4) inhibitor Minocycline extended release (Emrosi; Ximino) – tetracycline antibiotic Minocycline topical (HY01) – tetracycline antibiotic MTC-896 – melanocortin receptor antagonist Nitric oxide (Enovid; FabiSpray; NORS-0791; NORS-1002; NORS-2791; NORS-4002; NORS-6491; NORS) – nitric oxide donor ORG-101 (acne vulgaris vaccine; ORI-001; ORI-A-ce001) – immunostimulant, vaccine Radezolid (RX-01667; Rx-01_667; RX-103; RX-1741) – oxazolidone antibiotic Research programme: antimicrobial therapies - NovaBiotics – cell membrane permeability enhancers Research programme: synthetic cannabinoid therapeutics - Claritas Pharmaceuticals – cannabinoids (cannabinoid receptor modulators) Research programme: therapeutic antibody fragments - Kuur Therapeutics – various actions Silver dihydrogen citrate (SDC; Axenohl) – antiseptic/antibacterial Tazarotene topical (DFD-03) – retinoid X receptor agonist
=== Cherish the Light Years (2011–2012) === In April 2011, Matador Records released his second album, Cherish the Light Years. In July 2011, Cold Cave remixed "I Didn't See It Coming" by the band Belle and Sebastian. The song appeared on their 12-inch single "Come On Sister" released by Matador Records and Rough Trade Records. In April 2012, Cold Cave performed at the Solomon R. Guggenheim Museum between John Chamberlain sculptures as part of the museum's Divine Ricochet series. In October 2012, Cold Cave performed at the Getty Center.
Cloning of the YAP1 gene facilitated the identification of a modular protein domain, known as the WW domain. Two splice isoforms of the YAP1 gene product were initially identified, named YAP1-1 and YAP1-2, which differed by the presence of an extra 38 amino acids that encoded the WW domain. Apart from the WW domain, the modular structure of YAP1 contains a proline-rich region at the very amino terminus, which is followed by a TID (TEAD transcription factor interacting domain). Next, following a single WW domain, which is present in the YAP1-1 isoform, and two WW domains, which are present in the YAP1-2 isoform, there is the SH3-BM (Src Homology 3 binding motif). Following the SH3-BM is a TAD (transactivation domain) and a PDZ domain-binding motif (PDZ-BM) (Figure 1).
Other scarab beetles, for example, Coprophanaeus ensifer, build their burrows near carcasses for easier transportation of carrion pieces to offspring. Beetles that feed on human remains are important in forensic science. Terrestrial beetles such as checkered beetles and dermestid beetles colonize bodies in a predictable sequence and have well-characterized life cycles, so they can sometimes be used to estimate time of death. Aquatic beetles are less useful for estimating time of death but can cause physical damage to submerged bodies that must be distinguished from inflicted injuries when determining cause of death. For example, the facultatively necrophagous diving beetle Meridiorhantus validus creates postmortem channels and chambers in human bodies that must be differentiated from antemortem piercing injuries.
Sources: en.wikipedia.org
== Further reading == Combi, Chloe (2015). Generation Z: Their Voices, Their Lives. London: Hutchinson. OCLC 910606762. Palfrey, John; Gasser, Urs (2008). Born Digital: Understanding the First Generation of Digital Natives. Basic Books. McCrindle, Mark; Wolfinger, Emily (2014). The ABC of XYZ: Understanding the Global Generations. McCrindle Research.
== Professional organizations for clinical data management == International Network of Clinical Data Management Associations (INCDMA) aims at the promotion of collaboration among clinical data management groups around the world. It is an international forum for discussion of and feedback on current topics of relevance to the discipline of CDM. It is composed of members the boards of the SCDM, ACDM, DMB (France), PSDM (The Netherlands) who participate in the INCDMA proceedings and funding. It also regroups DM leaders and subject matter experts from Europe, North America, Israel, Japan, China and Australia. The Association for Clinical Data Management (ACDM) is a global organization founded in 1987 and is Empowering Excellence in Clinical Data Management. The ACDM represents a vibrant community of dedicated clinical research professionals who are passionate about enhancing the drug development process through fostering an environment that encourages continuous learning and the practical application of modern Clinical Data Management practices. With over 35 years of service to the data management community, the ACDM's unwavering commitment is to provide clear and effective platforms for its members to network, share experiences, and stay abreast of the latest regulations and standards in Clinical Data Management. Along with supporting members on their professional development journeys, offering opportunities to gain the skills and insights needed to excel in their careers and shape the future of data management.
Through this method, researchers can more effectively improve the functional properties of proteins to meet specific biotechnology or medical needs. Although this method has high requirements for information and technology and is relatively difficult to implement, with the development of computing technology and bioinformatics, the application prospects of semi-rational design in protein engineering are becoming more and more broad.
Sources: en.wikipedia.org
Cool, dark, and dry conditions are standard, with storage at minus twenty degrees Celsius or below. Desiccant and sealed vials limit moisture uptake. Repeated warming and cooling of the container is generally avoided.
There is no single agreed limit, and laboratory practice varies widely. Refrigeration slows degradation, and freezing aliquots is often described for longer holding. Any visible cloudiness or precipitate indicates the solution should be discarded.
Mass spectrometry provides the most direct confirmation through molecular mass. Reversed-phase chromatography supports purity assessment, and peptide mapping or amino acid analysis can corroborate sequence. No single method establishes both purity and identity on its own.
No. It is a synthetic analogue modeled on the first 29 residues of human GHRH. The substitutions and any linker are laboratory modifications rather than features of the endogenous peptide.