(A) Khc levels on embryonic lipid droplets are reduced in Khc heterozygotes (Khc27/+) compared to the wild type (WT). Equal amounts of total protein from purified lipid droplets were analyzed for Khc by Western blotting. This trend was reproduced in independent preparations; in some of them equal loading was additionally verified by probing for LSD2 (data not shown).
(B, C) Average stall forces in Khc27/+ heterozygotes are reduced compared to the wild type, both for plus-end (B) and minus-end (C) moving droplets.
(D, F) Stall-force distribution in Khc27/+ heterozygotes for plus-end (D) and minus-end (E) moving droplets. Both histograms show a single prominent peak whose position coincides with the 2.6± 0.5 pN peak in Fig. 3C, within the uncertainty estimated as half the bin size. (plus-end: 1.9 ± 0.5 pN, minus-end 2.1 ± 0.5 pN). A diminished peak at 5.2 pN is expected given the reduced number of motors on the lipid droplets in heterozygous embryos compared to wild type.