Frameshift (+1) proteins such as APP(+1) and UBB(+1) accumulate in sporadic cases of Alzheimer disease (AD) and in older subjects with Down syndrome (DS).
Taken together, these data show that co-expression of APP695 and APP(+1) affects the processing of APP695 in a pro-amyloidogenic way and this could gradually contribute to Alzheimer's disease pathology, as has been implicated in Down's syndrome patients.
The occurrence of +1 frameshifted proteins, such as amyloid precursor protein (APP+1) and ubiquitin-B (UBB+1) in Down syndrome (DS) has been linked to the onset of Alzheimer's disease (AD).