Display Accessibility Tools

Accessibility Tools

Grayscale

Highlight Links

Change Contrast

Increase Text Size

Increase Letter Spacing

Dyslexia Friendly Font

Increase Cursor Size

Jianping Hu

Professor

Department of Plant Biology
huji@msu.edu

Research: Molecular Mechanisms of Energy Organelle Dynamics and Interorganellar Interaction and Communication

In eukaryotic cells, biochemical reactions are compartmentalized in specific subcellular organelles. Plant mitochondria, peroxisomes, and chloroplasts are essential organelles in development and coordinate in a number of metabolic pathways required for energy capture, conversion, and metabolism. The Hu laboratory is interested in understanding molecular mechanisms underlying the dynamic behavior of peroxisomes and mitochondria and the role of these organelles in regulating photosynthesis and in plant interaction with the environment.

For adaptation, subcellular organelles can alter their abundance, morphology, and protein composition depending on the developmental and environmental conditions. One research goal of the Hu lab is to elucidate molecular mechanisms by which peroxisomes and mitochondria proliferate/divide, move/distribute, and turnover to ultimately understand how organelle dynamics contribute to plant robustness and stress response. To this end, we have identified and characterized components of the machineries that govern the biogenesis, division and proliferation of peroxisomes and mitochondria (Fig. 1) and revealed transcriptional and post-translational regulatory mechanisms of these processes. Recent efforts discovered the regulatory role of proteases and ubiquitin-proteasome mediated proteolysis in peroxisome and mitochondrial biogenesis and division, as well as adaptor proteins involved in the motility of these organelles along the cytoskeleton. We have also established a deep-learning framework to rapidly classify organelle morphology with the goal to facilitate large-scale screens for mutants in organelle dynamics.

Perixosome and mitochondrial division
Figure 1. Peroxisome and Mitochondrial Division 1 (PMD1) is a component of the peroxisome and mitochondrial division/proliferation machinery. Confocal images were taken from leaf epidermal cells of PMD1 loss-of-function mutant and overexpressor, showing abnormal morphologies of peroxisomes and mitochondria that are fluorescently labeled by organelle marker proteins CFP-PTS1 and COX4-YFP, respectively. Scale bar = 10 um.

The Hu lab also collaborates with other labs in the PRL and on campus to study the impact of peroxisomal metabolism on photosynthesis, and the role of photorespiration in stress response. Using the Dynamic Environment Phenotype Imager (DEPI), we have screened our collection of Arabidopsis peroxisome mutants and identified mutants showing photosynthetic deficiencies under light conditions that are more relevant to the natural environment, revealing regulatory links between photorespiration and photosynthesis under dynamic environmental conditions (Fig. 2). We are also exploring the role of photorespiration in plant-pathogen interaction.

Photosynthetic phenotypes of peroxisome mutants
Figure 2. Photosynthetic phenotypes were revealed in peroxisomal mutants under dynamic light conditions. Shown are heatmaps of four photosynthetic parameters, phi2, NPQ, qE and qI, in mutant relative to the WT. In each heatmap, x axis is time points, y axis is the ~150 peroxisomal mutants subjected to the screen, and the five columns represent five days of dynamic light treatment. The subgroup of mutants with lower phi2 is indicated by the black box, and mutants in this subgroup are linked to each other between the heatmaps by curved lines. Color code is under each heatmap to indicate the level of changes.

Our research has agricultural and economical relevance, as knowledge gained may provide molecular bases for developing strategies for rational engineering of crop plants to improve metabolism, bioenergy production, and defense against environmental stresses. Our research may also provide useful information to biomedical studies in curing human peroxisomal and mitochondrial diseases.

Contact

phone icon
envelope icon
map marker icon

Education

  • Postdoctoral Researcher, Howard Hughes Medical Institute, Salk Institute for Biological Studies, La Jolla, CA 
  • Ph.D., University of Georgia, Athens, GA
  • B.S., Peking University, Beijing, China

Publications

PubMed Search
Hu Publications

Hu Lab News

MSU's Jianping Hu receives NSF grant to shed light on plant growth, reproduction MSU's Jianping Hu receives NSF grant to shed light on plant growth, reproduction June 15, 2022

Jianping Hu, professor at the MSU-DOE Plant Research Laboratory (PRL) and the Department of Plant Biology, received a $900,000 grant from the National Science Foundation (NSF) to study the motility of cellular energy organelles, peroxisomes and mitochondria in particular, along the cytoskeleton in Arabidopsis thaliana.

Jianping Hu accepts leadership position as new director of MPS [LINK] Jianping Hu accepts leadership position as new director of MPS [LINK] January 11, 2022

Professor Jianping Hu has been appointed as the new director of the Molecular Plant Sciences (MPS) Graduate Program at Michigan State University.

More lab news