Polo-like kinase 2 genetic deletion does not alter rate of PFF-induced Lewy inclusion formation.A, In vivo multiphoton imaging from cortex in a Syn-GFP mouse at the days indicated after PFF injection showed formation of a new Lewy inclusion (yellow arrowhead) over the course of 19 days. A previously formed inclusion (white arrowhead), and examples of neurons expressing unaggregated Syn-GFP (yellow arrow) or no Syn-GFP (white arrow) are shown. Scale bar 10 μm. B, Left: The number of inclusions present in specific regions of interest over time, starting approximately 50 days after PFF injection, showed new formation essentially ending by approximately 100 days post PFF injection. Right: Calculated fast and slow rate constants for inclusion formation using a double exponential model showed no significant difference between PLK2 WT and KO animals (fast rate constant: WT = 0.142 ± 0.058, KO = 0.072 ± 0.004, unpaired t-test, two-tailed p = 0.3990; slow rate constant: WT = 0.055 ± 0.015, KO = 0.127 ± 0.077, unpaired t-test, two-tailed p = 0.2707; N = 52–664 inclusions per animal/3–5 animals per group). C, The growth of individual inclusions took approximately 2–3 weeks in both PLK2 WT and KO animals. Scale bar 20 μm.