Research Highlights

  • We developed a rapid and cost-effective Oxford Nanopore Target-Indexed-PCR (TIP) sequencing platform for digital quantification of RNA editing and maturation in plant organelle transcripts. This technical advance enables single-molecule analysis of chloroplast RNA editing and intron retention with high reproducibility and broad accessibility for studies of organelle–nucleus communication. Hua, Plant Direct 2025 doi:10.1002/pld3.70111.
  • We demonstrated that engineering ubiquitin supply can alter plant growth, proteasome function, and seed yield. By comparing two recombinant polyubiquitin expression systems in Arabidopsis, we found contrasting effects on growth vigor and reproductive output, suggesting that optimization of ubiquitin abundance, structure, and expression pattern may provide a synthetic-biology strategy for improving plant productivity. Yu et al., Plants 2024 doi:10.3390/plants13111485.
  • We developed a novel inducible CRISPR interference (iCRISPRi) approach for controlled knockdown of the essential chloroplast regulatory gene MORF2. This synthetic-biology strategy revealed a dose-dependent role of MORF2 in chloroplast RNA editing and uncovered its broader function in plastid retrograde signaling, stress responses, reactive oxygen species accumulation, and seedling morphogenesis. Yu and Hua., Frontiers in Plant Science 2023 doi:10.3389/fpls.2023.1146922.
  • We synthesized current strategies for deciphering plant protein ubiquitylation pathways, including bioinformatic prediction of ubiquitin writers, readers, and erasers; proteomic identification of ubiquitylated substrates; and functional-genomic characterization of E3 ligase–substrate relationships. This review also proposed a deleterious-duplication and genomic-drift model to explain the large, uneven expansion of the plant F-box gene superfamily, emphasizing the importance of prioritizing core and active E3 ligase genes for future functional studies. Hua., Journal of Experimental Botany 2023 doi:1093/jxb/erad354.
  • We discovered a developmental relay between the ubiquitin–26S proteasome system and autophagy during Arabidopsis silique and seed development. This work revealed that proteasome activity declines while autophagy flux rises during silique maturation, uncovering reciprocal turnover between these two major proteolytic systems and highlighting their coordinated roles in developmental proteostasis. Yu and Hua., Plant Journal 2022 doi:10.1111/tpj.15891.
  • We generated a fertile Arabidopsis ask1 mutant that enabled systematic discovery of ASK1-containing Skp1–Cullin1–F-box (SCF) ubiquitin ligase functions. Through genetic backcrossing, biochemical analysis, RNA-seq, and physiological assays, we demonstrated polymorphic roles of SCF complexes and uncovered broad functions of ASK1 in protein ubiquitylation, embryogenesis, seed development, floral organ formation, pollen viability, light signaling, circadian regulation, and auxin/ABA responses. Yapa et al., Plant Journal 2020 doi:10.1111/tpj.14939.
  • We generated the first comprehensive evolutionary framework for ubiquitin and ubiquitin-like protein modifiers in plants. By identifying 5,856 ubiquiton genes from 17 subfamilies across 50 plant genomes, we uncovered contrasting duplication histories among UB, SUMO, ATG8, and MUB genes. This work revealed that whole-genome duplication, tandem duplication, and retroposition differentially shaped plant ubiquitin-like modifier systems, providing new insight into the conserved and diversified functions of protein modification pathways in plants. Hua et al., Plant Journal 2018 doi:10.1111/tpj.13951.

Projects

UPS / F-box Biology

The ubiquitin-26S proteasome system regulates diverse cellular processes in eukaryotes. In plants, this system is especially large and complex, with more than 1,500 predicted components. Our lab studies how SCF ubiquitin ligases and F-box proteins regulate plant development, including seed development, germination, and early seedling growth. Training areas: genetics, molecular biology, CRISPR, genotyping, protein degradation assays, Arabidopsis development.

Autophagy and Proteostasis

The ubiquitin-proteasome system and autophagy pathway do not function independently. These two proteolytic systems interact to maintain protein homeostasis and regulate plant responses to developmental and environmental signals. Our lab investigates how ubiquitin-dependent mechanisms connect proteasomal degradation with selective autophagy. Training areas: protein biochemistry, autophagy markers, microscopy, stress biology.

Chloroplast Signaling

Chloroplast function depends on coordinated communication between the chloroplast and nucleus. Our recent work focuses on how cytoplasmic protein degradation regulates nucleus-encoded chloroplast proteins before or during plastid import. We ask how these degradation pathways affect chloroplast function, retrograde signaling, seed germination, and early seedling development. Training areas: chloroplast biology, RNA editing, transcriptomics, seedling phenotyping, microscopy.

Comparative Genomics & Transcriptomics

Gene duplication has greatly expanded many plant gene families. The unusually large size of the plant ubiquitin system provides an excellent model for studying how duplication, sequence divergence, and regulatory changes shape genome function. We combine comparative genomics, transcriptomics, and experimental validation to predict and test functions of ubiquitin-system genes. Training areas: bioinformatics, comparative genomics, RNA-seq, functional prediction.

Synthetic Biology & Protein Engineering

The rapid and selective action of ubiquitin-mediated protein degradation offers opportunities to engineer new regulatory circuits in plants. As an emerging direction, our lab is interested in using ubiquitin and selective autophagy pathways to control protein abundance, gene expression, and metabolic activities. Training areas: CRISPR-based genome editing and gene regulation, including knockout, knock-in, knockdown/CRISPRi, and activation/CRISPRa; molecular cloning, protein engineering, synthetic biology, and plant transformation.

Major Research Funding

    Ohio University OURC/Baker Fund (2026): $14,998.

    NSF-CAREER Award (2018-2024): $1.13 M.

    Ohio University Baker Fund (2017): $11,924.

    Ohio University Research Committee (OURC) Award (2016-2017): $7,958.

    Ohio University Startup Research Support (2014-2018).

Student Research Awards

    Emmanuel Olaoluwa, Ohio University Student Enhancement Award, 2026: $5,600.

    Jacob Sieg, Ohio University Provost's Undergraduate Research Fund, 2017: $1,489.

    William Vu, Ohio University Provost's Undergraduate Research Fund, 2017: $1,293.

Undergraduate Training Awards

    Ohio University PACE Undergraduate Research Support, multiple awards since 2015: $3,300 per award.

    Maddie Shelt, Ivan K. Smith Summer Research Fellowship (2022): $2,000.

    Noah Barber, Norman S. Cohn Summer Research Fellowship (2021): $2,000.