Emission of volatile organic compounds from petunia flowers is facilitated by an ABC transporter

Science ◽  
2017 ◽  
Vol 356 (6345) ◽  
pp. 1386-1388 ◽  
Author(s):  
Funmilayo Adebesin ◽  
Joshua R. Widhalm ◽  
Benoît Boachon ◽  
François Lefèvre ◽  
Baptiste Pierman ◽  
...  

Plants synthesize a diversity of volatile molecules that are important for reproduction and defense, serve as practical products for humans, and influence atmospheric chemistry and climate. Despite progress in deciphering plant volatile biosynthesis, their release from the cell has been poorly understood. The default assumption has been that volatiles passively diffuse out of cells. By characterization of aPetunia hybridaadenosine triphosphate–binding cassette (ABC) transporter, PhABCG1, we demonstrate that passage of volatiles across the plasma membrane relies on active transport.PhABCG1down-regulation by RNA interference results in decreased emission of volatiles, which accumulate to toxic levels in the plasma membrane. This study provides direct proof of a biologically mediated mechanism of volatile emission.

2021 ◽  
Author(s):  
Hichem Bouzidi ◽  
Ahmad Lahib ◽  
Nina Reijrink ◽  
Marius Duncianu ◽  
Emilie Perraudin ◽  
...  

<p>Atmospheric transformation processes have been extensively studied in the laboratory using simulation chambers with various designs and materials. These tools allow  kinetic experiments to be performed under well-controlled conditions whereby a selected volatile organic compound (VOC) is usually oxidized in synthetic air. While atmospheric chambers are invaluable to provide kinetic parameters that are needed in atmospheric chemical mechanisms, their limitation is that they do not test these chemical mechanisms under conditions that are representative of the complex atmosphere, i.e. containing multiple VOCs and inorganic species.</p><p>In the present work, a mobile rectangular atmospheric simulation chamber of ~ 9 m<sup>3</sup>, made of Teflon FEP foils, was built at IMT Lille Douai for laboratory and field studies. The whole setup – called DouAir – can be easily disassembled, transported and deployed in the field. This new tool allows trapping of real air masses on-site, providing observations on the fate of reactive trace gases, which when compared to box model simulations can provide a critical test of our understanding of atmospheric chemistry. The chamber allows both solar and artificial irradiation, the irradiance being monitored by spectroradiometry. The chamber is equipped with a large array of analytical instruments, including PTR-ToFMS and GC-MS for VOC measurements, CRM for total OH reactivity, PERCA for peroxy radicals, O<sub>3</sub> and NO<sub>x</sub> analyzers, and SMPS for aerosols. Here we describe the DouAir setup and will discuss characterization experiments carried out to validate the chamber. DouAir was tested for the first time during an intensive field campaign in the Landes forest (France) during summer 2018: CERVOLAND (Characterization of Emissions and Reactivity of Volatile Organic Compounds in the Landes Forest). Examples of experiments performed during CERVOLAND will be presented.</p>


2005 ◽  
Vol 169 (2) ◽  
pp. 285-295 ◽  
Author(s):  
Daniela A. Sahlender ◽  
Rhys C. Roberts ◽  
Susan D. Arden ◽  
Giulietta Spudich ◽  
Marcus J. Taylor ◽  
...  

Myosin VI plays a role in the maintenance of Golgi morphology and in exocytosis. In a yeast 2-hybrid screen we identified optineurin as a binding partner for myosin VI at the Golgi complex and confirmed this interaction in a range of protein interaction studies. Both proteins colocalize at the Golgi complex and in vesicles at the plasma membrane. When optineurin is depleted from cells using RNA interference, myosin VI is lost from the Golgi complex, the Golgi is fragmented and exocytosis of vesicular stomatitis virus G-protein to the plasma membrane is dramatically reduced. Two further binding partners for optineurin have been identified: huntingtin and Rab8. We show that myosin VI and Rab8 colocalize around the Golgi complex and in vesicles at the plasma membrane and overexpression of constitutively active Rab8-Q67L recruits myosin VI onto Rab8-positive structures. These results show that optineurin links myosin VI to the Golgi complex and plays a central role in Golgi ribbon formation and exocytosis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giulia Tedeschi ◽  
Lorenzo Scipioni ◽  
Maria Papanikolaou ◽  
Geoffrey W. Abbott ◽  
Michelle A. Digman

AbstractVoltage-gated potassium (Kv) channels are a family of membrane proteins that facilitate K+ ion diffusion across the plasma membrane, regulating both resting and action potentials. Kv channels comprise four pore-forming α subunits, each with a voltage sensing domain, and they are regulated by interaction with β subunits such as those belonging to the KCNE family. Here we conducted a comprehensive biophysical characterization of stoichiometry and protein diffusion across the plasma membrane of the epithelial KCNQ1-KCNE2 complex, combining total internal reflection fluorescence (TIRF) microscopy and a series of complementary Fluorescence Fluctuation Spectroscopy (FFS) techniques. Using this approach, we found that KCNQ1-KCNE2 has a predominant 4:4 stoichiometry, while non-bound KCNE2 subunits are mostly present as dimers in the plasma membrane. At the same time, we identified unique spatio-temporal diffusion modalities and nano-environment organization for each channel subunit. These findings improve our understanding of KCNQ1-KCNE2 channel function and suggest strategies for elucidating the subunit stoichiometry and forces directing localization and diffusion of ion channel complexes in general.


Author(s):  
Mario Vincenzo Russo ◽  
Ivan Notardonato ◽  
Alberto Rosada ◽  
Giuseppe Ianiri ◽  
Pasquale Avino

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid–liquid extraction and static headspace) followed by gas chromatography–electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L−1 in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g−1), antimony (77.7 µg g−1), strontium (12,039 µg g−1) and zinc (103 µg g−1), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g−1): the levels found in this paper (ranging between 1 and 5100 µg g−1) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.


Metabolites ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 21
Author(s):  
Yanhang Chen ◽  
Musavvara Kh. Shukurova ◽  
Yonathan Asikin ◽  
Miyako Kusano ◽  
Kazuo N. Watanabe

Curcuma amada Roxb. (Zingiberaceae), commonly known as mango ginger because its rhizome and foliar parts have a similar aroma to mango. The rhizome has been widely used in food industries and alternative medicines to treat a variety of internal diseases such as cough, bronchitis, indigestion, colic, loss of appetite, hiccups, and constipation. The composition of the volatile constituents in a fresh rhizome of C. amada is not reported in detail. The present study aimed to screen and characterize the composition of volatile organic compound (VOC) in a fresh rhizome of three C. amada (ZO45, ZO89, and ZO114) and one C. longa (ZO138) accessions originated from Myanmar. The analysis was carried out by means of headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-time-of-flight-mass spectrometry (GC-TOF-MS). As a result, 122 VOCs were tentatively identified from the extracted 373 mass spectra. The following compounds were the ten most highly abundant and broadly present ones: ar-turmerone, α-zingiberene, α-santalene, (E)-γ-atlantone, cuparene, β-bisabolene, teresantalol, β-sesquiphellandrene, trans-α-bergamotene, γ-curcumene. The intensity of ar-turmerone, the sesquiterpene which is mainly characterized in C. longa essential oil (up to 15.5–27.5%), was significantly higher in C. amada accession ZO89 (15.707 ± 5.78a) compared to C. longa accession ZO138 (0.300 ± 0.08b). Cis-α-bergamotene was not detected in two C. amada accessions ZO45 and ZO89. The study revealed between-species variation regarding identified VOCs in the fresh rhizome of C. amada and C. longa.


Sign in / Sign up

Export Citation Format

Share Document