PKD1 and infection: However, PKD1 shRNA infection prevented the increases in the serine phosphorylation of both the GluN2A (Fig. 6d) and GluN2B (Fig. 6e) subunits whereas infection of control shRNA did not alter the increases in the serine phosphorylation (Fig. 6f and g) induced by DHPG or high NMDA/glycine treatment.