Figure 5.

Microtubule cosedimentation of the DHC in the presence of synthetic peptides. (A) The Coomassie blue-stained portion of the gel containing the DHC band is shown above densitometric quantitation of the amount of DHC present in each lane. Lane 1 contains the repeated MAP1B motif peptide, lane 2 the non–MAP-like DHC sequence, lane 3 the control DHC sequence following the MT-binding region, and lane 4 the m₂′ sequence (see MATERIALS AND METHODS). Lane 5 shows a no-peptide control. Only the peptide in lane 4 produces a marked effect on dynein cosedimentation. For densitometry, the pelleted actin band was used to normalize loading. The y-axis measures total pixel density. (B) Similar to A, except the amount of m₂′ peptide was varied: 2.5, 0.5, and 0 mM in lanes 1–3, respectively.