Date of Award
5-12-2024
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Biology
Advisor(s)
Heather Coleman
Subject Categories
Biology | Life Sciences
Abstract
Secondary cell wall (SCW) biosynthesis plays a crucial role in plant development and biomass production, with implications for various industries, including biofuels and forestry. Understanding the regulatory mechanisms governing SCW formation is essential for manipulating plant cell wall composition and properties to improve biomass yield and quality. In this study, we investigated the regulatory mechanisms controlling SCW biosynthesis in poplar, focusing on the transcriptional regulation of PtrPARVUS2, a putative gene involved in SCW formation. The regulatory mechanisms governing SCW biosynthesis in poplar were investigated, with a focus on the transcriptional regulation of PtrPARVUS2. Bioinformatic analysis of the PtrPARVUS2 promoter revealed motifs associated with environmental response, suggesting its involvement in plant development and responses to environmental stimuli. Expression pattern analysis indicated predominant expression of PtrPARVUS2 in vascular tissues, particularly the outer layer of the stem at primary stage of growth, and tissue-specific activity confirmed by EGFP expression driven by its promoter. Our results highlight the significance of PtrPARVUS2 in guard cell function and phytohormone signaling pathways, providing strong promoters for guard cell and epidermis-targeted biotechnology approaches. Additionally, six transcription factors (TFs), PtrC2H2ZF1, PtrC2H2ZF2, PtrARF5a, PtrNAC127, PtrBLH, and PtrCORONA, were found to bind to the PtrPARVUS2 promoter, with PtrBLH emerging as a negative regulator of xylan biosynthesis. These findings contribute to our understanding of TF-mediated transcriptional regulation in plant development and SCW formation. Furthermore, our study elucidated temperature and phytohormone-mediated regulation of PtrPARVUS2 transcription, highlighting the intricate adaptive responses of plants to environmental cues. Overall, our findings advance our understanding of SCW biosynthesis in poplar, with potential implications for enhancing biomass production and quality in woody plants. Future directions include functional characterization of PtrPARVUS2 through genetic manipulation techniques such as CRISPR/Cas9 to generate knockout or overexpression lines. This will allow for phenotypic analyses to assess the impact of PtrPARVUS2 on plant growth, SCW formation, and abiotic stress responses. Regulatory network elucidation will involve further investigation into the hierarchical relationships and feedback loops among TFs involved in SCW biosynthesis, providing deeper insights into the transcriptional regulation of this process. Synthetic promoter research will focus on designing and testing novel synthetic promoters tailored for precise control of gene expression in SCW biosynthesis pathways, offering potential applications in enhancing biomass production and quality in woody plants.
Access
Open Access
Recommended Citation
Wang, Dan, "Transcriptional and Environmental Regulation of a Putative Xylan Biosynthesis Gene, PtrPARVUS2 in poplar" (2024). Dissertations - ALL. 1951.
https://surface.syr.edu/etd/1951
