PLANT-RNA-MET · A newly discovered role for mRNA methylation in controlling plant gene expression

A newly discovered role for mRNA methylation in controlling plant gene expression

The ability of plants to grow, develop and respond to the environment depends upon the ability to precisely co-ordinate gene expression. As development proceeds, or defences to pathogens are mounted, the expression of some genes needs to be silenced, while other must be activated or amplified. Therefore, explaining how gene expression is regulated is important to understand how plant development and immunity are controlled. In many aspects, the principles of gene expression regulation in plants resemble that of other complex organisms, like humans or animals. Genes are segments of DNA, that during gene expression are transcribed by an enzyme called RNA polymerase II (Pol II) complexed with other components, into precursor messenger RNA (pre-mRNA). The efficiency of transcription depends on many factors, e.g DNA modifications that make DNA accessible or inaccessible to Pol II complexes. In the next step, pre-mRNA is processed in many ways into mature form - messenger mRNA (mRNA), that can affect mRNA fate in the cell. For example, the same pre-mRNA can be processed into mRNAs that differ in the position at which they end as a result of a process known as alternative polyadenylation. Since mRNA is next translated into protein, differences in pre-mRNA processing can determine what protein the gene will code for or what the lifetime of mRNA will be. Associated with pre-mRNA processing, is a newly recognised layer of gene regulation involving RNA modifications. For example, m6A RNA methylation is essential for regulation of mRNA fate, including mRNA degradation and translation efficiency. Our understanding of the diverse functional impacts of m6A in plants is still emerging. In this proposal, we aimed to explain the function of m6A mRNA modification in plant gene expression, with the major focus on plant immune response genes. To do this, we designed our experimental plan to recognise how m6A affects transcription termination and alternative polyadenylation, and to identify important factors involved in this regulation. Arabidopsis thaliana was used in this study because it is a model experimental system. A better understanding of the role of m6A in tuning gene expression in Arabidopsis facilitates the new knowledge and understanding required for the development of crops with improved growth and immunity against pathogens.

Data: CORDIS, © European Union