What goes wrong with the protein Dynein, that leads to Primary Ciliary Dyskinesia ?

Answer 1

Dynein is one of the proteins that help the cilia to generate their beating pattern. Each cilium has a central pair of microtubules and an outer set of nine 'doublets' - pairs comprising one complete and one incomplete microtubule, arranged in a circular pattern. Each of these microtubules are attached to the basal body of the cell, and each doublet is also attached to the central pair by radial spokes.

Each complete microtubule of the outer circle has two arms made of dynein - a shorter straight outer arm, and a longer hooked inner arm. These arms provide the means by which each pair of microtubules slide on each other, thereby bending the cilium, and generating the typical wave like movement you would expect.

In Primary Ciliary Dyskinesia, there are genetic defects in the dynein arms, and different defects will result in different movement patterns of the cilia...
If there is a partial or complete absence of the outer dynein arms, then the cilia will have a slower beat frequency, and tend to have a stiff flickering type of movement. So if the normal beat frequency is in the region of 1000-1500 bpm and mucous clearance happens at a rate of about 30ml/min, then you can see how a slower and less efficient rate of beating in the cilia will mean poor clearance, and the development of recurrent infections.

Defects can also affect the inner dynein arms, or both inner and outer arms, and these may result in a stiff, straight forward-backward movement with a much smaller amplitude than normal, and there may also be radial spoke defects or defects where the central pair of microtubules end up in the outer circle, and this can result in a wild gyrating type movement which will not clear anything - this is the transposition defect.

The basic upshot of any of these defects is that the cilia do not clear the airways like they're supposed to, and this will result in pooling of secretions and recurring infections in the sinuses or lungs.

I hope that helps.

Answer 2

Dynein is a class of protein responsible for the bending of cilia, and Primary Ciliary Dyskinesia is a heterogeneous group of inherited disorders characterised by a structural and generalised abnormality of cilia which renders them immotile or dysmotile. The most common clinical expressions of this condition are chronic upper and lower airway disease and male infertility. ..... Evidence has been found that a genetic defect of the gene(s) for dynein, leading to a congenital lack of dynein arms in cilia and sperm tails, was responsible for both the respiratory and fertility problems.

Answer 3

it is a defect in the genetic coding of left right dynein in the cilia which lines the respiratory tract. The coding defect is unknown as yet although dynein is a key structural protein in cilia

Answer 4

this protein helps cilia(small projections ) present in respiratory tract , genital tract to move and perform its job so when this protein is defected or abscent you will have what we call (immotile cilia syndrome or Primary Ciliary Dyskinesia as you called it .....there are many variants for this problem (like Kartagner syndrome ,young syndrome)
in general what the patient will come with is a complaint of respiratory infections,reduced fertility in female and sterility in male.