| Title: | Structural changes in plastids of developing Splachnum ampullaceum sporophytes and relationship to odour production |
| Author(s): | McCuaig B; Dufour SC; Raguso RA; Bhatt AP; Marino P; |
| Address: | "Department of Biology, Memorial University of Newfoundland, St John's, NL, Canada" |
| ISSN/ISBN: | 1438-8677 (Electronic) 1435-8603 (Print) 1435-8603 (Linking) |
| Abstract: | "Many mosses of the family Splachnaceae are entomophilous and rely on flies for spore dispersal. Splachnum ampullaceum produces a yellow- or pink-coloured hypophysis that releases volatile compounds, attracting flies to the mature moss. The biosynthetic sources of the visual and aromatic cues within the hypophysis have not been identified, and may be either symbiotic cyanobacteria or chromoplasts that break down lipids into volatile compounds. Here, we used transmission electron microscopy and gas chromatography-mass spectrometry (GC-MS) to investigate the sources of these attractants, focusing on different tissues and stages of maturation. Microscopy revealed an abundance of plastids within the hypophysis, while no symbiotic bacteria were observed. During plant maturation, plastids differentiated from amyloplasts with large starch granules to photosynthetic chloroplasts and finally to chromoplasts with lipid accumulations. We used GC-MS to identify over 50 volatile organic compounds from mature sporophytes including short-chain oxygenated compounds, unsaturated irregular terpenoids, fatty acid-derived 6- and 8-carbon alcohols and ketones, and the aromatic compounds acetophenone and p-cresol. The hypophysis showed localised production of pungent volatiles, mainly short-chain fermentation compounds and p-cresol. Some of these volatiles have been shown to be produced from lipid oxidase degradation of linolenic acid within chromoplasts. However, other compounds (such as cyclohexanecarboxylic acid esters) may have a microbial origin. Further investigation is necessary to identify the origin of fly attractants in these mosses" |
| Keywords: | "Alcohols/analysis Bryopsida/chemistry/*growth & development Cresols/analysis Gas Chromatography-Mass Spectrometry Microscopy, Electron, Transmission Odorants/analysis Plastids/*chemistry/ultrastructure Volatile Organic Compounds/*analysis/chemistry Develo;" |
| Notes: | "MedlineMcCuaig, B Dufour, S C Raguso, R A Bhatt, A P Marino, P eng P20 RR016461/RR/NCRR NIH HHS/ RR-P20 RR 016461/RR/NCRR NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. England 2014/09/13 Plant Biol (Stuttg). 2015 Mar; 17(2):466-73. doi: 10.1111/plb.12256. Epub 2014 Nov 25" |
