Las proteínas PAT1Nuevos reguladores multifuncionales del procesamiento de los ARNm en Arabidopsis thaliana

Abstract

The major goal of plants, like all other living organisms, is to maximize their reproductive success. To this, it is crucial an adequate control of their growth and development, which is mainly governed by changes in gene expression. In the last years, different studies have revealed that controlling the stability of messenger RNAs (mRNAs) plays a key role in regulating gene expression. Therefore, identifying the molecular mechanisms underlying mRNA stability is essential to understand how plants develop and reproduce. Previous studies in Arabidopsis have demonstrated that the cytoplasmic LSM1-7 complex, an activator of decapping, determines the levels of 5´ CAP and, as a result, the stability of a specific subset of mRNAs, depending on the external and internal stimuli perceived by plants. Whether this ability is a particular feature of the LSM1-7 complex or it is shared by other components of the decapping machinery, is still unknown. PAT1 proteins are also components of this machinery, and they are highly conserved along evolution. Several reports have shown that PAT1p and PAT1b, function as activators of decapping in yeast and humans, respectively. In addition, it has been recently described that both proteins are involved in controlling RNA stability in a decapping-independent way, and that PAT1b regulates the splicing process. Interestingly, the Arabidopsis genome contains three genes encoding PAT1 paralogous, named PAT1, PAT1H1 and PAT1H2. So far, however, only PAT1 has been described to act as an activator of decapping...