A 17-aa peptide sequence within the cytoplasmic N-terminus of mouse neprilysin-like protease-a.
The amyloid beta-peptide (Ab) of 39 to 43aa (Ab40, Ab42, Ab43) is constitutively produced in brain upon proteolysis of the b-amyloid precursor protein (APP). In the young and healthy humans, Ab is rapidly catabolized before it can be deposited in the brain. However, upon aging or the onset of familial Alzheimer's Disease, alterations in either synthesis or degradation/clearance of Ab may contribute to amyloid depositions in the brain. Ab is susceptible to a number of in vivo and in vitro proteases like cathepsin-D and M-13 metalloproteases. The M-13 family includes several members of zinc-dependent proteases like damage-induced neuronal endopeptidase (DINE), product of phosphate regulating gene with homologies to endopeptidases on the X chromosome (PHEX), neutral endopeptidase 24.11 or neprilysin (NEP) and neprilysin-like proteases (NEPLs). NEPLs (alpha, -beta, gamma) arise from the alternative splicing of a single NELPS gene and show ~54% sequence homology. M13 members are generally type II transmembrane proteins consisting of a single polypeptide chain with Zinc binding HEXXH motif, a short cytoplasmic tail, a transmembrane segment and an extra-cytoplasmic domain containing the enzyme active site.
NEPL-a (variously called SEPD/splice 1) is a type II trans-membrane metallopeptidase (~100kD non-glycosylated and 120kD glycosylated) containing a highly glycosylated polypeptide chain of 742aa with a HEXXH zinc-binding consensus, cytoplasmic tail and a large extracellular catalytic domain. NPL-a lacks a 23aa sequence present in N-terminal of NEPL-b. In contrast to NEP and NEPL-b which exist in membrane-bound as well as soluble forms, NEPL-a is expressed as membrane-bound form only. In comparison to NEP, the NEPL-a has lower affinity and/or smaller Vmax for Ab and cannot proteolyze cell secreted Ab40 or Ab42 in vivo. Unlike NEP, NEPL-a is not a major in vivo peptidase for degrading endogenous Ab however, it might degrade Ab in Alzheimer patients where Ab is accumulated in excess and an Ab-degradative pathway, alternative to NEP, exists.
Applications:Suitable for use in ELISA and Antibody Blocking. Because of its low MW (<3kD), not suitable for Western Blot. Other applications not tested.
Recommended Dilutions:ELISA: 50-100ng of control peptide/wellAntibody Blocking: 5-10ug per 1ug of N2030-32 (purified IgG) or 1ul of N2030-30 (antiserum). Optimal dilutions to be determined by the researcher.
Storage and Stability: May be stored at 4°C for short-term only. For long-term storage, aliquot and store at -20°C. Aliquots are stable for at least 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
