Assistant Research Professor
Ph.D. 2012, Tsinghua University, China
Multiple roles of RNA-binding proteins (RBPs) in plant mRNA localization and post-transcriptional gene regulation
Messenger RNA (mRNA) localization, the process by which mRNAs are transported to specific subcellular compartments for localized translation, is an essential and universal mechanism that efficiently drives protein targeting in eukaryotic and prokaryotic organisms. Localization of mRNAs is well studied in yeast and animal cells, but only a few examples have been reported in higher plants.
Using mRNA localization in developing rice seeds as a model system, our laboratory has assembled the best example of active RNA transport in plants. In rice endosperm cells, the storage protein mRNAs are distributed to different subdomains of the cortical endoplasmic reticulum (ER). Prolamine mRNAs are distributed to the protein body ER (PB-ER) that delimit the prolamin intra-cisternal inclusions while glutelin mRNAs are located on adjacent cisternal-ER.
mRNA localization relys on RNA sequence recognition and binding by specific RNA-binding proteins (RBPs) to assemble the essential mRNP complexes required to transport mRNAs to their destination. To further understand the regulatory mechanism of mRNA localization in plant cells, our research focuses on the identification and characterization of specific RBPs and their co-assembly to form multiprotein complexes, which are required for the coordinated transport of mRNAs to the varied destinations. More than 200 RBPs have been identified from rice endosperm cells in the project and our current research suggests that these RBPs form various complexes to regulate mRNA recognition, nuclear export and intracellular transport during the mRNA localization process. Moreover, those RBPs also participate in assembly of stress granules (SGs) and processing bodies (PBs) to dynamically sort mRNAs for storage and degradation, respectively. We utilize multiple approaches, including transcriptomics and proteomics, to further decipher the multiple roles of RBPs in plant mRNA localization and post-transcriptional gene regulation.