Figure 1. S5A mice express equivalent levels of LPL without evidence of S5 phosphorylation.
A. Schematic of LPL with three identified phosphorylation sites (S5, S7 and T89) in the regulatory N-terminal domain indicated. ABD = actin-binding domain. B. Schematic indicating that “S5A” represents endogenous LPL locus in which S5 is converted to non-phosphorylatable alanine residue. C. Immunoblot of whole spleen lysates from WT, S5A and LPL−/− mice. Anti-actin immunoblot indicates equivalent protein loading. Anti-LPL immunoblot indicates equivalent expression of endogenous LPL in S5A mice. Specific anti-S5 phosphorylation antibody indicates complete ablation of S5 phosphorylation of native LPL in S5A mice at baseline. D. Confocal microscopy of F-actin morphology of residential peritoneal macrophages from WT and S5A mice. F-actin illuminated using phalloidin (green), talin illuminated using anti-talin mAb (red), and nuclei using DAPI (blue). Arrows indicate clusters of podosomes. Scale bar = 6 μm. Images representative of two independent experiments.