Fig. 1.

Kinesin inactivates more rapidly at higher temperatures. (A) Freshly thawed kinesin dimer is active (t = 0; left bar) and sediments with microtubules in the presence of AMP-PNP. Aging for 1.5 h (on ice) or 40 min (at warmer temperatures) resulted in decreased interactions with microtubules (all other bars), with increasing temperature resulting in accelerated inactivation. (B) The decrease in MT association detected by MT pelleting in A was accompanied by a decrease in MT-stimulated ATPase activity of K349 monomer. (C) Original data are summarized in B.