title: Mechanosensitivity below Ground: Touch-Sensitive Smell-Producing Roots in the Shy Plant Mimosa pudica.
abstract: The roots of the shy plant Mimosa pudica emit a cocktail of small organic and inorganic sulfur compounds and reactive intermediates into the environment, including SO2, methanesulfinic acid, pyruvic acid, lactic acid, ethanesulfinic acid, propanesulfenic acid, 2-aminothiophenol, S-propyl propane 1-thiosulfinate, phenothiazine, and thioformaldehyde, an elusive and highly unstable compound that, to our knowledge, has never before been reported to be emitted by a plant. When soil around the roots is dislodged or when seedling roots are touched, an odor is detected. The perceived odor corresponds to the emission of higher amounts of propanesulfenic acid, 2-aminothiophenol, S-propyl propane 1-thiosulfinate, and phenothiazine. The mechanosensitivity response is selective. Whereas touching the roots with soil or human skin resulted in odor detection, agitating the roots with other materials such as glass did not induce a similar response. Light and electron microscopy studies of the roots revealed the presence of microscopic sac-like root protuberances. Elemental analysis of these projections by energy-dispersive x-ray spectroscopy revealed them to contain higher levels of K(+) and Cl(-) compared with the surrounding tissue. Exposing the protuberances to stimuli that caused odor emission resulted in reductions in the levels of K(+) and Cl(-) in the touched area. The mechanistic implications of the variety of sulfur compounds observed vis-à-vis the pathways for their formation are discussed.
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.) rmusah@albany.edu.
authors.forename: Rabi A
authors.initials: RA
authors.lastname: Musah
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: Ashton D
authors.initials: AD
authors.lastname: Lesiak
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: Max J
authors.initials: MJ
authors.lastname: Maron
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: Robert B
authors.identifier: http://orcid.org/0000-0002-6624-8530
authors.initials: RB
authors.lastname: Cody
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: David
authors.initials: D
authors.lastname: Edwards
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Fowble
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: A John
authors.identifier: http://orcid.org/0000-0002-5910-8687
authors.initials: AJ
authors.lastname: Dane
authors.affiliation: Department of Chemistry, State University of New York at Albany, Albany, New York 12222 (R.A.M., A.D.L., M.J.M., K.L.F., M.C.L.); andJEOL USA, Inc., Peabody, Massachusetts 01960 (R.B.C., D.E., A.J.D.).
authors.forename: Michael C
authors.initials: MC
authors.lastname: Long
mesh_terms: D002246:Carbon Disulfide / Q000378:metabolism; D002849:Chromatography, Gas; D020285:Cryoelectron Microscopy; D004777:Environment; D007477:Ions; D013058:Mass Spectrometry; D040542:Mechanotransduction, Cellular; D031298:Mimosa / Q000378:metabolism*; D008954:Models, Biological; D009812:Odorants; D018517:Plant Roots / Q000378:metabolism* / Q000648:ultrastructure; D036226:Seedlings / Q000378:metabolism / Q000648:ultrastructure; D013052:Spectrometry, X-Ray Emission; D013457:Sulfur Compounds / Q000378:metabolism; D014110:Touch; D055549:Volatile Organic Compounds / Q000378:metabolism
chemical_list: D007477:Ions; D013457:Sulfur Compounds; D055549:Volatile Organic Compounds; D002246:Carbon Disulfide