CHGA Human, His

Chromogranin-A (CgA) is a member of the granin family of neuroendocrine secretory proteins. It is found in the secretory vesicles of neurons and endocrine cells. This protein plays a crucial role in the formation of secretory granules and is a precursor to several biologically active peptides, including vasostatin, pancreastatin, and parastatin .

The recombinant human Chromogranin-A with a His tag is a full-length protein, typically ranging from amino acids 19 to 457 . The His tag, a sequence of histidine residues, is added to the C-terminus of the protein to facilitate purification and detection. This recombinant protein is often expressed in baculovirus-infected insect cells or human embryonic kidney cells (HEK293) .

The recombinant Chromogranin-A protein is purified to a high degree, with a purity level exceeding 85% as determined by SDS-PAGE . The endotoxin level is kept below 1 EU/µg, making it suitable for various biochemical applications . Another source mentions a higher purity level of over 90%, with an endotoxin level below 0.10 EU per µg .

Chromogranin-A (Human Recombinant, His Tag) is used in various research applications, including:

• SDS-PAGE: For analyzing the protein’s purity and molecular weight .
• ELISA: To measure the protein’s binding ability in functional assays .
• Cell Culture: As a standard or control in experiments involving neuroendocrine cells .

Chromogranin-A is not just a structural protein; it also has significant biological functions. It is a precursor to peptides that act as autocrine or paracrine modulators of the neuroendocrine system . These peptides can influence various physiological processes, including hormone secretion and blood pressure regulation.

The recombinant protein is typically lyophilized and can be reconstituted in PBS. It is stable for up to 12 months when stored at -20 to -70°C. After reconstitution, it should be stored under sterile conditions at 2 to 8°C for up to one month or at -20 to -70°C for up to three months .