Figure S3.

Purification Scheme of SERF1a-Induced “On-Pathway” aSyn Aggregates, Related to Figure 4

(A) after approx. 30 hr agitation at 1400 rpm and 37°C, aggregates were isolated by size exclusion chromatography (see experimental procedures), where they eluted as a high molecular size peak.

(B) The fractions corresponding to this peak (50-60) were ThT-reactive (Ex/Em 442/482 nm, slit widths 20/20 nm).

(C–E) The aggregates did not contain SERF1a, as shown by SDS-PAGE/immunoblotting (c = SERF1a control), and they were composed exclusively of aSyn (D). They ran as a mixture of high molecular weight and monomeric species on SDS-PAGE, but as aggregates-only on a native gel (E), attesting their partial resistance to SDS.

(F) TEM image of the pooled aggregate fractions.

(G) Dynamic light scattering identified the aggregates as a polydisperse mixture of particles with a diameter between 20 and ≥ 400 nm.