<p>Primary mouse cortical neurons were infected with lentivirus carrying LRP1-shRNA or NT-shRNA for 4 days. Cell surface proteins were labeled with biotin in live neurons, and the cell lysates were precipitated with streptavidin beads. (<b><i>A, B</i></b>) The precipitates and total cell lysates were examined by Western blot to detect cell surface GluA1 and total GluA1, respectively. The ratio of surface GluA1 versus total GluA1 was quantified (<b><i>A</i></b>). Similarly, ratio of surface GluA2/3 versus total GluA2/3 was analyzed (<b><i>B</i></b>). (<b><i>C</i></b>) In control and LRP1-knockdown neurons, the expression of total GluA1 and phosphorylated GluA1 (pSer-845 and pSer-831) were analyzed by Western blot. The phosphorylation at Ser-845 (<b><i>D</i></b>) and Ser-831(<b><i>E</i></b>) sites of GluA1 versus total GluA1 were quantified. The data are plotted as mean ± SD (n = 3). N.S., not significant; *, p<0.05; **, p<0.01.</p
