These motors were made for walking.

Area of Science:

• Biochemistry
• Molecular Biology
• Cell Biology

Background:

• Kinesins are ATP-dependent motor proteins crucial for intracellular transport and microtubule network organization.
• Their ~40 kDa motor domain exhibits diverse motility and remodeling mechanisms due to sequence variations.
• Previous studies explored individual kinesin-tubulin interactions, but systematic comparisons are lacking.

Purpose of the Study:

• To systematically compare kinesin sequences and their microtubule (MT) contacts.
• To correlate sequence variations with differences in kinesin speed, processivity, and MT remodeling activity.
• To elucidate the design-function relationship of kinesins based on their MT interactions.

Main Methods:

• Review of existing literature and high-resolution structural data from X-ray crystallography and cryo-electron microscopy.
• Analysis of kinesin-tubulin complexes and their interfaces.
• Comparative analysis of kinesin subfamily sequences and their tubulin footprints.

Main Results:

• Sequence variations within the kinesin motor domain directly influence their tubulin footprint.
• These variations explain observed differences in kinesin speed, processivity, and MT remodeling capabilities.
• High-resolution structures reveal precise kinesin-MT interfaces, aiding in understanding molecular mechanisms.

Conclusions:

• Kinesin sequence variations are key determinants of their diverse molecular activities and MT interactions.
• Understanding these structure-function relationships is essential for deciphering kinesin roles in cellular processes.
• Advancements in structural biology accelerate the elucidation of kinesin design principles.