(draft) BIOL Lecture 4 Microtubule motor proteins Intermediate Filaments

Describe the role of kinesins and dyneins in cellular transport.

Kinesins and dyneins are microtubule-based motor proteins that transport various types of cargo, along microtubules powered by ATP hydrolysis.

Kinesins typically move cargo toward the (+) end (anterograde).

Dyneins typically transport cargo towards the (-) end (retrograde).

Examples of cargo include 

• membrane-bound vesicles 

• proteins 

• organelles

What direction do kinesins typically move cargo?

Towards the (+) end (anterograde)

What direction do dyneins typically move cargo?

Toward the (-) end (retrograde)

What are some exaples of cargo microtubule-based motor protiens transport.

• Membrane bound vesicles

• Proteins

• Organells

What is a dimer?

A molecule or molecular complex consisting of two identical molecules linked together.

Describe the structure of kinesin-1.

Kinesin-1 is a dimer made up of two heavy chains an associated light chains, with a total molecular weight of about 380,000 Da.

It contains a pair of globular N-terminal head domains, connected by a short flexible linker domain to a central stalk, an ends in a pair of small globular tail domains that assocuate with the light chains.

The neck region determines the direction of movement

How does kinesin-1 move along the microtubule.

The kinesin family motor (or head domains) contains the ATP binding site and the microtubules-binding site of tthe motor.