The goal of this research is to discover how a single plant protein, called SERRATE (SE), carries out two very different functions in the cell. One of SE's functions is to make small microRNAs (miRNAs) from larger RNA molecules, and the other function is to quiet the activity of certain potentially harmful DNA elements in the genome. The bi-functional nature of SE is thought to arise from its ability to interact with different protein partners, and this research aims to test that idea. Because SE is conserved in both plants and animals, the results could have far-reaching benefits for many fields of science and for society, such as in plant biotechnology where the results could contribute to improvement of agricultural traits. This project is well-suited for undergraduate student participation and provides hands-on training in genetics, genomics, and biochemistry. The project also offers opportunities for graduate students and postdoctoral fellows to develop their professional careers at the forefront of an emerging field, and thus the research will contribute to building a creative and highly skilled workforce to support the steady growth of the U.S. economy.
SE is known to be a core component of the miRNA processing machinery (microprocessor) in plants. The SE ortholog in mammals is known to function as a transcription factor. Preliminary evidence suggests that interaction of SE with a chromatin-remodeling factor is associated with its function in miRNA processing, whereas interaction with a histone methyltransferase may mediate its function in silencing transposable elements. Experimental aims will explore the mechanisms underlying these two functions. Results that implicate SE activity in miRNA biogenesis could provide new strategies to better regulate miRNA production and to improve the efficacy and safety of technologies and therapies that depend on small RNAs. Moreover, exploring the novel function of SE in regulating transposable elements will lead to new discoveries uniting the fields of RNA metabolism and transcriptional silencing, and may also provide new ideas about how to conquer disorders in plants and animals that result from the mis-regulation of chromatin-level gene silencing.
