Before we delve into details let's introduce you to dynein...

Dynein is a multi-subunit motor protein that converts chemical energy (ATP) into mechanical energy in order to travel along microtubules. Utilising ATP allows the protein to mobilise a linker domain which drives movement. Dynein motors are involved in several processes:

Axonemal dynein:

* Causes cilia and Flagella beating

Intraflagellar transport dynein:
* Aids axoneme formation

Cytoplasmic dynein:
* Transports intracellular cargo and organelles
* Controls centrosome and spindle assembly in mitosis
* Localises RNA
* Helps gathering misfolded proteins

Figure 1: Visual animation showing the movement of dynein along a microtubule 1 (See reference list)

What were the researchers (Schmidt et al., 2012) aiming to discover?


They investigated the structure of the motor domain in an attempt to understand it's function. The motor domain is a 300kDa protein complex composed of six ATP hydrolysing AAA+ domains (AAA1-6). A 3.3Å crystal structure of the motor domain (with no ATP bound) was obtained from the Yeast strain Saccharomyces cerevisiae in order to explore the following questions:

1) Do conserved docking sites exist for the linker protein. If so what are they like?

2) Does conformation of the linker change upon motor domain binding ADP?

3) What is the relationship between ATP hydrolysis in AAA1 and position of linker?

4) What role do the ATPase domains AAA2-AAA4 play in dynein function?