Staining Worm Neurons ..

As we all know, the chemosensory neurons in worms are stained by the lipophilic dyes such as DiL, FITC…

Does anyone know, what is the mechanism of the neuron staining?

Like, are the receptors of the respective neurons are responsible for dye uptake or the dye simple diffuse through the body cuticle?

Any responses will be highly appreciated… :slight_smile:

ah the devil is always in the detail :-\ .

If you read the Hedgecock et al. paper, they observed a reduced uptake of FITC in unc-33 and unc-44 mutants which have shorter (and therefore a reduced surface area of membrane) cilia. However, beyond this, little is expanded upon regarding uptake mechanisms as I assume they assumed FITC was passively transported through the cilial membrane.

However, ASE and ASG did not appear to fill and they too are ciliated and open to the external environment like ADF, ASH, ASI, ASJ, ASK & ADL.

ASE and ASG are involved in chemoattraction, but then so are other, FITC +ve amphid neurones.

It may well be the specific roles of ASE/ASG in chemoattraction (and hence their channels and transporters) that set them aside from the other ciliated amphid neurones.

One possibility is that FITC is specifically excluded from ASE/ASG rather than it being specifically taken up by the other amphid neurones.

But this is mainly my speculation, others may nail the reason with a simple reference…

Steve

Thanks for your detailed reply…

So you mean this dye uptake is due to the shorter surface area of the cilia ?

What about the DiL? Same mechanism ?

Thanks.

for FITC the suggestion was that a reduced surface area led to reduced FITC uptake…but this was only a suggestion.

For Dil, read the following summary which explains how Dil works;

http://tools.invitrogen.com/content/sfs/manuals/mp00282.pdf

Steve

Thank you :slight_smile:

Any other exchange of ideas will be highly appreciated…