title: Protein Dynamics in Young Maize Root Hairs in Response to Macro- and Micronutrient Deprivation.
abstract: Plants increase their root surface with root hairs to improve the acquisition of nutrients from the soil. The unicellular character of root hairs and their position at the root surface make them an attractive system to investigate adaptive processes of rhizodermal cells that are in direct contact with the soil solution. In young maize seedlings, roots are densely covered with root hairs, although nutrient reserves in the seed are sufficient to support seedling growth rates for a few days. We used a label-free quantitative proteomics approach to study protein abundance adjustments in 4 day old root hairs grown in aeroponic culture in the presence and absence of several macro- and micronutrients. Compared to the proteome of root hairs developed under full nutrition, protein abundance changes were observed in pathways related to macronutrient (N, P, K, and Mg) deficiencies. For example, lack of N in the medium repressed the primary N metabolism pathway, increased amino acid synthesis, but repressed their degradation, and affected the primary carbon metabolism, such as glycolysis. Glycolysis was similarly affected by K and P deprivation, but the glycolytic pathway was negatively regulated by the absence of the micronutrients Fe and Zn. In contrast, the deprivation of Mn had almost no affect on the root hair proteome. Our results indicate either that the metabolism of very young root hairs adjusts to cellular nutrient deficiencies that have been already experienced or that root hairs sense the external lack of specific nutrients in the nutrient solution and adjust their metabolism accordingly.
authors.affiliation: †Department of Plant Systems Biology, University of Hohenheim, Garbenstraße 30, 70599 Stuttgart, Germany.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.affiliation: ‡Institute of Crop Science, Nutritional Crop Physiology, University of Hohenheim, Fruwirthstraße 20, 70599 Stuttgart, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Phillip
authors.affiliation: ‡Institute of Crop Science, Nutritional Crop Physiology, University of Hohenheim, Fruwirthstraße 20, 70599 Stuttgart, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Neuhäuser
authors.affiliation: †Department of Plant Systems Biology, University of Hohenheim, Garbenstraße 30, 70599 Stuttgart, Germany.
authors.forename: Waltraud X
authors.initials: WX
authors.lastname: Schulze
authors.affiliation: ‡Institute of Crop Science, Nutritional Crop Physiology, University of Hohenheim, Fruwirthstraße 20, 70599 Stuttgart, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Ludewig
mesh_terms: D002853:Chromatography, Liquid; D016000:Cluster Analysis; D000069599:Crop Production / Q000379:methods; D007700:Kinetics; D008274:Magnesium / Q000378:metabolism / Q000494:pharmacology; D053858:Metabolic Networks and Pathways / Q000187:drug effects; D018977:Micronutrients / Q000378:metabolism* / Q000494:pharmacology; D009584:Nitrogen / Q000378:metabolism / Q000494:pharmacology; D010455:Peptides / Q000378:metabolism; D010748:Phosphopeptides / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism / Q000494:pharmacology; D010940:Plant Proteins / Q000145:classification / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism / Q000494:pharmacology; D020543:Proteome / Q000145:classification / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D053719:Tandem Mass Spectrometry; D003313:Zea mays / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*
chemical_list: D018977:Micronutrients; D010455:Peptides; D010748:Phosphopeptides; D010940:Plant Proteins; D020543:Proteome; D010758:Phosphorus; D008274:Magnesium; D009584:Nitrogen; D011188:Potassium
keywords: Zea mays; iron; macronutrient; micronutrient; nitrogen; nutrition; phosphorus; root hair