Beta-Amyloid (1-42), rat

β-Amyloid production results from cleavage in the extracellular domain of APP by the β-secretase , which results in the production of the APP C-terminal fragment C99. This fragment is further cleaved by the γ-secretase at residues 40-42 to produce β-amyloid 40 and 42 peptides. β-amyloid aggregation and neuritic plaque formation are pathologic hallmarks of AD.

Beta-Amyloid (1-42), rat is a synthetic amyloid-beta (Aβ) research peptide. Amyloid-beta peptides are proteolytic products of amyloid precursor protein. Sequence length and residue composition strongly influence aggregation: Aβ42 generally aggregates more rapidly than Aβ40, and C-terminal fragments containing residues in the 34-42 region can adopt stable beta-structure. Truncated, reverse-sequence, isotopically labeled, or chemically modified Aβ constructs are therefore best interpreted as distinct research reagents rather than assumed equivalents of native Aβ40 or Aβ42.

• amyloid aggregation and fibrillization studies
• LC-MS/HPLC analytical reference work
• Aβ sequence-length and modification comparisons
• antibody, binding, and assay controls

The exact sequence, phosphorylation state, residue numbering, terminal modifications, labels, and species context should be matched to the intended assay. Sequence motifs support experimental interpretation but do not by themselves establish absolute enzyme specificity or native biological activity.

1. Sequence determinants of enhanced amyloidogenicity of Aβ42 relative to Aβ40
2. Molecular determinants of amyloid deposition: synthetic beta-protein fragments
3. Impact of sequence on assembly of short amyloid peptides