Issues

APOE is one of the major risk factor genes for late-onset Alzheimer's disease. APOE encodes apolipoprotein E, a secreted protein that is highly expressed by astrocytes and microglia, whilst expression can be induced in neurons. In the study by Muñoz et al., CRISPR/Cas9 genome editing was used as 'molecular scissors' to target the APOE DNA sequence, in order to specifically knock down the expression of apolipoprotein E in neuronal cells. APOE knock down reduced expression of the gene encoding the enzyme that cleaves apolipoprotein E, HTRA1, suggesting a feedback loop between APOE and HTRA1 expression. Read their full article in Bioscience Reports (volume 41, issue 2).