title: The root as a drill: an ethylene-auxin interaction facilitates root penetration in soil.
abstract: Plant roots forage the soil for water and nutrients and overcome the soil's physical compactness. Roots are endowed with a mechanism that allows them to penetrate and grow in dense media such as soil. However, the molecular mechanisms underlying this process are still poorly understood. The nature of the media in which roots grow adds to the difficulty to in situ analyze the mechanisms underlying root penetration. Inhibition of ethylene perception by application of 1-methyl cyclopropene (1-MCP) to tomato seedlings nearly abolished the root penetration in Soilrite. The reversal of this process by auxin indicated operation of an auxin-ethylene signaling pathway in the regulation of root penetration. The tomato pct1-2 mutant that exhibits an enhanced polar transport of auxin required higher doses of 1-MCP to inhibit root penetration, indicating a pivotal role of auxin transport in this process. In this update we provide a brief review of our current understanding of molecular processes underlying root penetration in higher plants.
authors.affiliation: School of Life Sciences, University of Hyderabad, Hyderabad, India.
authors.forename: Parankusam
authors.initials: P
authors.lastname: Santisree
authors.forename: Sapana
authors.initials: S
authors.lastname: Nongmaithem
authors.forename: Yellamaraju
authors.initials: Y
authors.lastname: Sreelakshmi
authors.forename: Maria
authors.initials: M
authors.lastname: Ivanchenko
authors.forename: Rameshwar
authors.initials: R
authors.lastname: Sharma
mesh_terms: D001692:Biological Transport / Q000235:genetics; D003521:Cyclopropanes / Q000494:pharmacology; D005030:Ethylenes / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism* / Q000494:pharmacology; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D009154:Mutation; D010937:Plant Growth Regulators / Q000378:metabolism* / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D036226:Seedlings / Q000254:growth & development; D015398:Signal Transduction / Q000187:drug effects; D012987:Soil
chemical_list: D003521:Cyclopropanes; D005030:Ethylenes; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D010940:Plant Proteins; D012987:Soil; C036216:ethylene; C412563:1-methylcyclopropene