|Human Cell lysate that Human APP / Protease nexin-II transfected / overexpressed for Western blot (WB) positive control. The whole cell lysate is provided in 1X Sample Buffer (1X modified RIPA buffer+1X SDS loading buffer).|
|A DNA sequence encoding the human APP-751 isoform (NP_958816.1) (Met 1-Leu 669) was expressed with the C-terminal fused Fc region of human IgG1.|
|The recombinant human APP/Fc is a disulfide-linked homodimeric protein after removal of the signal peptide. The reduced monomer consists of 890 amino acids and predicts a molecular mass of 101 kDa. By SDS-PAGE under reducing conditions, the apparent molecular mass of rhAPP/Fc monomer is approximately 150-160 kDa due to the glycosylation.|
|Cell lysate was prepared by homogenization in ice-cold modified RIPA Lysis Buffer with cocktail of protease inhibitors (Sigma). Cell debris was removed by centrifugation. Protein concentration was determined by Bradford assay (Bio-Rad protein assay, Microplate Standard assay). The cell lysate was boiled for 5 min in 1 x SDS loading buffer (50 mM Tris-HCl pH 6.8, 12.5% glycerol, 1% sodium dodecylsulfate, 0.01% bromophenol blue) containing 5% b-mercaptoethanol, and lyophilized.|
|Modified RIPA Lysis Buffer: 50 mM Tris-HCl pH 7.4, 150 mM NaCl, 1mM EDTA, 1% Triton X-100, 0.1% SDS, 1% Sodium deoxycholate, 1mM PMSF.|
|12.5% SDS-PAGE Stained with Coomassie Blue after protein purification.|
|Samples are stable for up to twelve months from date of receipt.|
|1. Centrifuge the tube for a few seconds and ensure the pellet at the bottom of the tube. 2. Re-dissolve the pellet using 200μL pure water and boil for 2-5 min. 3. Store the lyophilized cell lysate at 4℃. After re-dissolution, recommend to aliquot it into smaller quantities and store at -80℃.|
|1 X Sample Buffer (1 X modified RIPA buffer+1 X SDS loading buffer).|
|Store at 4℃. After re-dissolution, aliquot and store at -80℃.|
|Western blot (WB): Use at an assay dependent dilution.|
Other Applications: Not tested.
Optimal dilutions/concentrations should be determined by the end user.
Amyloid precursor protein (APP) is a type I transmembrane protein expressed in many tissues and concentrated in the synapses of neurons, and is suggested as a regulator of synapse formation and neural plasticity. APP can be processed by two different proteolytic pathways. In one pathway, APP is cleaved by β- and γ-secretase to produce the amyloid-β-protein (Aβ, Abeta, beta-amyloid) which is the principal component of the amyloid plaques, the major pathological hallmark of Alzheimer’s disease (AD), while in the other pathway, α-secretase is involved in the cleavage of APP whose product exerts antiamyloidogenic effect and prevention of the Aβ peptide formation. The aberrant accumulation of aggregated beta-amyloid peptides (Abeta) as plaques is a hallmark of AD neuropathology and reduction of Abeta has become a leading direction of emerging experimental therapies for the disease. Besides this pathological function of Abeta, recently published data reveal that Abeta also has an essential physiological role in lipid homeostasis. Cholesterol increases Abeta production, and conversely A beta production causes a decrease in cholesterol synthesis. Abeta may be part of a mechanism controlling synaptic activity, acting as a positive regulator presynaptically and a negative regulator postsynaptically. The pathological accumulation of oligomeric Abeta assemblies depresses excitatory transmission at the synaptic level, but also triggers aberrant patterns of neuronal circuit activity and epileptiform discharges at the network level. Abeta-induced dysfunction of inhibitory interneurons likely increases synchrony among excitatory principal cells and contributes to the destabilization of neuronal networks. There is evidence that beta-amyloid can impair blood vessel function. Vascular beta-amyloid deposition, also known as cerebral amyloid angiopathy, is associated with vascular dysfunction in animal and human studies. Alzheimer disease is associated with morphological changes in capillary networks, and soluble beta-amyloid produces abnormal vascular responses to physiological and pharmacological stimuli.