Multiple roles of NUP1 in Arabidopsis growth and development
Abstract
The nuclear pore complex (NPC) is the gateway between the nucleus and cytoplasm, which provides the passage for transport of RNA, protein, and other molecules into and out of the nucleus. NPC is conserved across all eukaryotes and plays a vital role in various cellular processes. However, compared to other organisms, the study of NPC in plants is limited. Although more than 30 different types of nucleoporin proteins in the model plant Arabidopsis thaliana have been identified, none of those proteins has been studied in detail. In this thesis, I focused on one such protein named NUCLEOPORIN1 (NUP1) and investigated its role in seed germination and pollen development.
Since the expression of NUP1 is highest in seeds, I proposed and tested the hypothesis of NUP1 participation in seed germination especially under various abiotic stresses. Genome-wide transcriptomic analysis revealed alteration in abscisic acid (ABA) related genes in nup1. I also found that NUP1 interacts and regulates ABA INSENSITIVE 5 (ABI5), a major negative regulator of germination. Another important function of NUP1 is its role in fertility. NUP1 also plays a major role in pollen development. I compared the development of pollen in the Col-0 to that of nup1 mutant plants. Pollen study indicates the possible role of NUP1 in pollen nuclei migration during pollen tube growth, which directly affects the double fertilization in Arabidopsis.
The results from my thesis contribute to the understanding of the roles of NUP1 during seed germination and pollen development, which are both very important in agriculture. The knowledge generated from this work will help to develop better crops in the future.