Hi Ruben,

If your protein acts as a part of a multimeric complex, the lack or the excess of the protein might produce the same phenotype. For example, if this complex is important under stress condition, in absence of the protein the function of complex could be compromised. However, an excess of the protein might perturb the stoichiometry of the complex impairing its function. There are some examples in the literature (interactions between members of the TALE homeodomain superfamily).

It is also possible that by expressing the protein ectopically in cells and tissues where it should not be expressed, a opposite phenotype is produced.

I hope this might help.

Best,

Fernando

Interesting insight, because these are actually transcription factors and they are known to form a complex. I look into those examples, thanks a lot!

Ruben

Hi Ruben

Fernando is right, but you have to be sure that your OX plants are fine. Some times overexpression lines tends to cosupression with the time, giving you phenotypes that remenber the mutant phenotype. Check different independent lines of the OX, to confirm that the expression levels are still high.

Best

Vicent

Hello Vicente, Stefano,

Yep, that's an important consideration. We always work with at least two independent lines and both (with different levels of overexpression) are showing the same photosynthetic perturbation, although at different levels compared to the mutant. Also, they have an additional phenotype that is crystal clear and different to the mutant, so we know that there is no cosuppression at work. Thanks!

Cheers,

Ruben