Dear all,
I have been trying to find any markers that could be used to differentiate between males and hermaphrodites before L4? Do any exist or are they both the same till L4?
Thank you,
-JHP
“Before L4” is a broad category; it might help to be more specific about what you want.
In newly hatched L1s there are a number of differences that can be detected using Nomarski:
The HSNs are present in hermaphrodites but not males, in a distinctive position.
The CEMs are present in males but not hermaphrodites, and have a distinctive Nomarski morphology.
The B cell is much larger in the male, and the B cell is easy to find.
There are differences in the coelomocytes that I’d have to look up, I can’t remember offhand exactly what there are.
After L1, but before L4, there are differences in gonad development, large differences in shape that can be spotted using a dissecting scope (because the gonad crowds out the intestine and so you get patches of the animal that appear clear using a dissecting scope).
There are some gfp reporters that can help, at various stages.
tph-1::gfp is marker of serotonergic neurons, including the HSN. Normal tph-1::gfp reporters are not expressed in the HSN before L4, but the first tph-1 paper describes a construct expressed in the HSNs of L1s. It might even be possible to use a pan-neuronal gfp reporter, or a reporter for a gene that expresses in a larger subset of neurons including the HSN, such as unc-86.
There are coelomocyte reporters that should in theory work, though I don’t recall seeing them used for this purpose.
lag-2::gfp expresses in the hermaphrodite distal tip cells and the male linker cell, and might make it easier to spot differences in the developing gonad either earlier or more easily than using a normal dissecting microscope.
There are vulval development markers usable in the L3, and I assume (though haven’t looked) also markers of male-specific development usable in L3 - though my favorite gfp reporter for the CEMs can’t be used before L4.
Thank you for your response this is all helpful information that I can put towards my project.
-JHP