Seed germination under risky circumstances: the fundamental role of PUMILIO proteins

Worldwide, agriculture is facing increased challenges like drought and salinity. Many studies address stress tolerance of crops, but the importance of seed germination in these conditions is often overlooked. When environmental conditions worsen after sowing, germination can be rapidly halted. Little is known about the regulation and flexibility of the germination process, but an essential step is the translation of seed stored mRNAs. Studies indicate that RNA binding proteins (RBPs) are in control of this process; the PUMILIO (PUM) family of RBPs seems to be especially active during germination, but their precise function is largely unknown in plants. In this project, I aim at revealing the role of Arabidopsis PUMILIO (APUM) proteins during seed germination. I will first identify all RBPs that are active during germination. Second, a mutant analysis of APUM genes will reveal their function in seed germination. Then, I will analyse the most essential APUM in detail, by identifying its target mRNAs and the protein cofactors with which the APUM associates. Finally, I will collaborate with Bejo Zaden, to repeat some of the proposed experiments on their crop seeds. This allows the direct transfer of knowledge from Arabidopsis to crops. Overall, this project will contribute to the development of stress tolerant seeds, so that the Dutch seed sector can maintain a high quality and ensure the germination of their seeds, also during the global climate crisis.

Funding: Graduate School Experimental Plant Science, Bejo Zaden