PE-22-28

PE-22-28 Research Standard

PE-22-28 (CAS 1801959-12-5) is a seven-amino-acid peptide corresponding to residues 22–28 of the sortilin propeptide, supplied as a 10 mg lyophilized powder in a 3 mL vial. Understanding what it is requires following where it comes from, because the well-characterised molecule in this lineage is not this fragment but its longer relative, spadin.

Where this peptide comes from

• Sortilin is cleaved to release a propeptide. Sortilin, also called neurotensin receptor-3 (NTSR3), is synthesised as a precursor and converted to the mature protein by the convertase furin in late Golgi compartments. That maturation releases a 44-amino-acid propeptide, referred to as PE — which is where this product's name originates.^[2]

• The propeptide and its analogue block TREK-1. Sortilin physically interacts with the two-pore-domain potassium channel TREK-1, and both the propeptide and its synthetic analogue spadin block TREK-1 activation.^[2]

• What is established is established for spadin. Spadin binds TREK-1 specifically with an affinity around 10 nM and blocks channel activity in COS-7 cells, cultured hippocampal pyramidal neurons and CA3 neurons in brain slices. In vivo it increased 5-HT neuron firing rate in the dorsal raphe nucleus, and a four-day intravenous course enhanced hippocampal CREB phosphorylation and neurogenesis.^[1] Those numbers describe spadin. PE-22-28 is a shorter fragment from the same propeptide, and data on one should not be quoted as data on the other.

• The target itself is well defined. TREK-1 is a two-pore-domain potassium channel; mice lacking the TREK-1 gene show a depression-resistant phenotype resembling antidepressant treatment, which is what made channel antagonists interesting in the first place.^[1]

Research Applications

Primary fields of in vitro and preclinical laboratory investigation include:

• TREK-1 electrophysiology by patch clamp in transfected cells, cultured neurons and brain slices.^[1]

• Comparative potency work against spadin and the full 44-residue propeptide — the obvious gap, since the fragment's own affinity is not established here.^[1,2]

• Sortilin/TREK-1 interaction studies, including co-immunoprecipitation and colocalisation.^[2]

• Serotonergic firing rate measurement in the dorsal raphe.^[1]

Analytical Documentation

Purity and identity vary by manufacturing lot. Kimera Chems does not publish a single fixed purity figure for this item; refer to the batch-specific Certificate of Analysis (COA) issued for the lot received, which reflects third-party analytical testing for that lot.

References

1. Mazella J, Pétrault O, Lucas G, et al. Spadin, a sortilin-derived peptide, targeting rodent TREK-1 channels: a new concept in the antidepressant drug design. PLoS Biol. 2010;8(4):e1000355. doi:10.1371/journal.pbio.1000355
2. Mazella J, Borsotto M, Heurteaux C. The involvement of sortilin/NTSR3 in depression as the progenitor of spadin and its role in the membrane expression of TREK-1. Front Pharmacol. 2019;9:1541. doi:10.3389/fphar.2018.01541

Storage & Handling

Store at controlled room temperature, sealed and protected from light.

Storage guidance is a house recommendation. Analytical documentation is per-lot release testing.

Related Research Compounds

• Compound 7p
• Cerebrolysin
• Lemairamin
• Adrenochrome

Research Use Only Disclaimer: This product is labeled and sold "For Research Use Only - NOT FOR HUMAN CONSUMPTION." It is not a drug, dietary supplement, food, cosmetic, or medical device, and it is not approved by the FDA or any other regulator for human or veterinary use. It is supplied to approved account holders as a research chemical for laboratory use and must be handled in accordance with applicable law.