abolished/normal discrimination of growing end PMID:10574765

[ValWood]

Jacky requested:

Boundary of non growing cell end maintained During monopolar growth the boundary of the non growing cell end is maintained and is distinct from the cell body

Boundary of the non growing cell end not maintained During monopolar growth the boundary of the non growing cell end is not maintained and is indistinguisable from the cell body

This is a phenotype where a marker, which is usually cortical and excluded for the growing ends, is no longer excluded. Monopolar mutants are used to demonstrate this, because they still have a non growing end, but I think the phenotype should be "generic".

perhaps: abolished/normal discrimination of growing end

figure 2

[mah11]

Hmmm. This is one of those awkward cases where what you want to say is actually an interpretation of an observed phenotype. The observation in this figure is simply "protein mislocalized to cell cortex of non-growing cell tip" (which doesn't exist in FYPO but would be easy to add), or not.

To go beyond the observation it would help to konw how a normal process could be named and defined - it's something along the lines of "setting the boundary of a cell end", but all of the words I've thought of so far would probably clash with more specific developmental biology usage (e.g. boundary determination or boundary specification).

In any case, "discrimination" doesn't really work here because it means recognizing an existing distinction between two or more different things, not bringing the distinction into existence.

(I would also love to have a way to track directly observed vs. inferred-by-curator phenotypes some day ...)

[ValWood]

The problem is that is a all a bit artificial/artifactual.

The marker which is used (Cor1 fragment) actually turned out to be a fragment of Nse6. So, itself is not normally localised to the cortical region, but it's fragment is.

So its actually "protein mislocalized to cell cortex of non-growing cell tip, of a protein which has a mutant which locates to the cortex , but is normally nuclear". Which clearly we can't capture.

This fortuitous marker is then used to show that orb1 mutants can no longer discriminate their growing end.

This phenotype is observed in mutants which only grow monopolarly so they know there is only a single growing end. Then they show that orb1 does not recognize that this single end is growing, but I'm interpreting that this is only to make a simpler model and that orb2 is generally deficient in discriminating between growing and non-growing ends (which also fits with the other data).

Jacky, did I understand that correctly ? @jvhayles

[ValWood]

Oh I see what you mean about discrimination. I'm thinking...

[mah11]

me too. maybe "delineation"? we should run it by David Hill ...

there are probably other cases where a region within a cell is somehow defined, so GO should come up with something generally applicable (if only they weren't dysfunctional ...)

[ValWood]

I was just thinking "loss of cell end specification" ? which sounds along the same lines...

[mah11]

unfortunately, "specification" is one of those words that has a really specialized meaning in dev biol, so it would be better if we can think of something that won't clash :/