Most of the vegetal production loss is mainly due to drought, salinity and extreme temperatures (Epstein et al., 1980; Yancey et al., 1982). This cause that the study of tolerance processes to this stresses will be crucial, not only in the biologic viewpoint, where exist plants capable to tolerate extreme concentrations of salt and drought, but rather, in the human viewpoint, the study of this processes benefits, without doubt, the economical aspect of agriculture. This would resolve, becoming very optimistic, the problem of starvation in the vast deserted or saline soils, although, becoming more realistic, in the not too distant future, we will be able to use seawater not very treated, to irrigate the vegetal cultures.
Following this approach, and using previous data of the functional screening of Arabidopsis thaliana’s genes in yeasts (Forment et al., 2002), we began this PhD taking RCY1 like main character.
This gene supposedly involved in mRNA splicing was subjected to study, following the dogma of its relationship with salt stress tolerance in yeast.
We carried out several studies in Arabidopsis thaliana to check if in this plant, RCY1 take part in salt tolerance processes. We investigated too the action mechanisms of this gene with and without salt.
First, we checked the increase of the expression of this gene in Arabidopsis thaliana, while treatments with salt (NaCl y LiCl), drought (irrigation absence) and osmotic stress (sorbitol). In other words, beginning from a low basal expression and subjecting Arabidopsis thaliana to this stresses, the mRNA levels of RCY1 will rise meaningfully. 
We check too, that wild types plants, without salt treatments, have an important expression of the gene, only in pollen, anther and stigma, but not in the other tissues. This tissues have an important process of physiological desiccation, because of that we think that RCY1 is involved in drought tolerance.
Later, we make transgenic Arabidosis plants, overexpressing RCY1. This transgenic plants become salt and drought tolerant.
The K.O. RCY1 mutant plants don’t show sensitive while salt and drought treatments, We check that the homozigotic plants, without RCY1 expression are androsterile because they haven’t mature pollen.
The cellular location of RCY1-GFP fusion is clear. The protein is located in nucleolus and a few nuclear speckles (This data was obtained at Dr. Peter Shaw’s lab, in the John Innes research Center, Norwich, UK).
Finally we demonstrate too that the overexpression of RCY1 confers protection against salt during transcription.