The role of phospholipid metabolism in maize adaptation to low phosphorus and cold conditions

The role of phospholipid metabolism in maize adaptation to low phosphorus and cold conditions

Talk given at the Plant Nutrition and Efficient Utilization session of the 7th International Crop Science Congress in Beijing, August 2016.

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Rubén Rellán Álvarez

August 20, 2016
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Transcript

  1. 1.

    The role of phospholipid metabolism in maize adaptation to low

    phosphorus and cold conditions Rubén Rellán Álvarez www.rrlab.org Langebio, Cinvestav, Irapuato. Mexico ruben.rellan@cinvestav.mx
  2. 2.

    Plants use two strategies to increase P availability Local response

    Root system Lateral root formation and growth Root hair formation architecture Pi recycling Pi transport Primary root growth inhibition Pi recovery Systemic response Phosphate homeostasis sensing Pi Pi Pi Pi Pi TRENDS in Plant Science ystemic responses. Sensing of phosphate (Pi) by the model plant Arabidopsis triggers a set of adaptive responses that can be gr ce) responses. This review focuses on developmental adaptations that are mainly controlled at the local level. However, system Peret et al. 2011 PubMedID 21684794
  3. 3.

    Root Area Local responses increase top soil root surface exploration

    area number of basal roots determined by number of whorls (about 4 roots/whorl) wild 20 15 5 0 1 2 3 no. whorls more basal roots = more soil volume explored 2 whorls, up to 8 basal roots 3 whorls, up to 12 basal roots 4 no. basal roots 10 cultivated horl 1 horl 2 horl 3 (b) (c) piece. Exploiting the phenome P-inneficient P-efficient Lynch al . 2012 PubMedID 22527403 Rellan-Álvarez al . 2015 PubMedID 26287479 Depth/Width Shoot Area
  4. 4.

    Systemic responses transport P where is most needed Acidification of

    the rhizosphere P recycled from vegetative tissues ZmPht1;2 ZmPht1;5 ZmPht1;6 ZmPht1;7 ZmPht1;8a ZmPht1;8b ZmPht1;9 ZmPht1;11 ZmPht1;13a ZmPht1;13b ZmPht1;13c (T01) ZmPht1;13c (T02) ZmPht1;13d ZmPht1;14 0 4,795 Counts (log-transformed) 0 4 logFC +P -P logFC +P -P logFC root leaf * * * * * * * * Upregulation of P transporters N (Field, 1983; Hirose & Werger, 1987; Franklin & A ˚gren, 2002). Redistribution of P for optimal plant C gain has been little studied, but the same principles are expected to apply as for N. Adequate concentrations of P are important to maintain high rates of photosynthesis (Rychter & Rao, 2005), and rates of P flowering Solidago altissim photosynthesis. In contra by Thomas & Sadras (20 ity, Reich et al. (2009) fo species still had a positi 0 20 40 60 80 100 0 20 40 60 80 100 120 (a) Time after sowing (d) P content (mg) Whole plant Vegetative plant Fig. 5 Schematic time course of (a) the phosphorus (P) content of a monocarpic crop plant from germination to maturity; (b) net P fluxes from seed and soil to vegetative plant and grain, as well as net remobilization from vegetative plant to grain. Approximate values based on studies of growth and P accumulation shown in Fig. 4. New Phytologist Li et al . 2007 PubMedID 17592130 Sawers et al . Unpublished Lambers et al . 2012 PubMedID 22937909 ZmPht1;2 ZmPht1;5 ZmPht1;6 ZmPht1;7 ZmPht1;8a ZmPht1;8b ZmPht1;9 ZmPht1;11 ZmPht1;13a ZmPht1;13b ZmPht1;13c (T01) ZmPht1;13c (T02) ZmPht1;13d ZmPht1;14 0 4,795 Counts (log-transformed) 0 4 logFC +P -P logFC +P -P logFC root leaf * * * * * * * * ZmPht1;2 ZmPht1;5 ZmPht1;6 ZmPht1;7 ZmPht1;8a ZmPht1;8b ZmPht1;9 ZmPht1;11 ZmPht1;13a ZmPht1;13b ZmPht1;13c (T01) ZmPht1;13c (T02) ZmPht1;13d ZmPht1;14 0 4,795 Counts (log-transformed) 0 4 logFC +P -P logFC +P -P logFC root leaf * * * * * * * * ZmPht1;2 ZmPht1;5 ZmPht1;6 ZmPht1;7 ZmPht1;8a ZmPht1;8b ZmPht1;9 ZmPht1;11 ZmPht1;13a ZmPht1;13b ZmPht1;13c (T01) ZmPht1;13c (T02) ZmPht1;13d ZmPht1;14 0 4,795 Counts (log-transformed) 0 4 logFC +P -P logFC +P -P logFC root leaf * * * * * * * * logFC -P/+P root shoot
  5. 7.

    Inorganic Pi 18 What P containing compounds is the plant

    actually recycling? Lambers et al . 2012 PubMedID 22937909
  6. 8.

    Nucleic Acids 40 Inorganic Pi 18 What P containing compounds

    is the plant actually recycling? Lambers et al . 2012 PubMedID 22937909
  7. 9.

    Ester-P 18 Nucleic Acids 40 Inorganic Pi 18 What P

    containing compounds is the plant actually recycling? Lambers et al . 2012 PubMedID 22937909
  8. 10.

    Phospholipids 24 Ester-P 18 Nucleic Acids 40 Inorganic Pi 18

    What P containing compounds is the plant actually recycling? Lambers et al . 2012 PubMedID 22937909
  9. 11.

    Phospholipids are part of glycerolipids & essential building blocks of

    membranes Glycerol 3-P Polar Head Precursors Fatty Acids adapted from: http://big.cea.fr/drf/big/english/PCV/LiPMB Basic components of glycerolipids
  10. 12.

    Phospholipids are part of glycerolipids & essential building blocks of

    membranes Glycerol 3-P Polar Head Precursors Fatty Acids Polar Lipids Phospholipids Galactolipids Essential Intermediates Phosphatidic A Diacylglycerol Sulfolipids adapted from: http://big.cea.fr/drf/big/english/PCV/LiPMB Basic components of glycerolipids
  11. 13.

    Phospholipids are synthesized in the ER, Galactolipids in the chloroplast

    envelope phosphatidate in the tgd1 mutant and the localization of TGD1 in the chloroplast inner envelo 37] suggest that the transported molecule could also be phosphatidate. To understand this latt precise localization of the phosphatidic acid phosphatase (PAP) involved in the transformation MGDG PLD PLC PC DAG E PA E PA E PA E MGDG MGD1 MGD2, MGD3 PAP Endomembrane Plastid envelope OM PAP PA P + DGDG DGD1, DGD2 DGDG Thylakoids LysoPC PLA 2 LysoPC PC LysoPC acyltransferase IM DAG E PG Mitochondria SQDG DAG E DAG P + ransfers towards and outwards the chloroplast envelope. PC is present in the outer leaflet of the outer envelope membra zed in the ER, not in the plastid. It may be transferred from ER to the envelope directly or through its conversion Block et al . 2015 PubMedID 25868077
  12. 14.

    Although the pathways are well studied, new compounds/pathways are being

    discovered comprehensive chemical metabolic phenotyping of cells, to investigate lipid remodelling in detail and to identify a new key lipid molecule that has an essential role in protection against P-depletion stress. neutral los conclusion diacyl-3-O reported i a b 20 16 10 2 0 Relative intensity Retention time (min) +P −P P (corr) 4 6 8 12 14 18 –1 1 0 –0 MGDG StGlc GlcCer SQDG PG DGDG Unknown lipid UK1 (GlcADG) PE PI PC Figure 1 | A new lipid inducibly accumulates in Arabidopsis under P depletion. (a) Wild were transferred to either P-sufficient ( þ P, blue line) or P-depleted ( À P, red line) mediu leaves were analysed by HILIC-MS. The total ion current detected by the negative ion mo identified as GlcADG) appeared only under P-limited conditions. (b) S-plot of OPLS-DA ba The S-plot demonstrates the covariance versus the correlation in conjunction with the var The variables that showed maximum change, and therefore strongly contributed to the cla plot. The variables that did not significantly vary are plotted in the middle. Each point rep Red stars denote the [M–H]À ions of the UK1 species, indicating that the change in the P-limiting treatment. The molecules at the top and bottom are listed in Tables 1 and 2. 2 NATURE COMMUNICATIONS | 4:15 & 2013 Macmillan Publishers Limited. All r Okazaki et al . 2013 PubMedID 23443538
  13. 15.

    Although the pathways are well studied, new compounds/pathways are being

    discovered comprehensive chemical metabolic phenotyping of cells, to investigate lipid remodelling in detail and to identify a new key lipid molecule that has an essential role in protection against P-depletion stress. neutral los conclusion diacyl-3-O reported i a b 20 16 10 2 0 Relative intensity Retention time (min) +P −P P (corr) 4 6 8 12 14 18 –1 1 0 –0 MGDG StGlc GlcCer SQDG PG DGDG Unknown lipid UK1 (GlcADG) PE PI PC Figure 1 | A new lipid inducibly accumulates in Arabidopsis under P depletion. (a) Wild were transferred to either P-sufficient ( þ P, blue line) or P-depleted ( À P, red line) mediu leaves were analysed by HILIC-MS. The total ion current detected by the negative ion mo identified as GlcADG) appeared only under P-limited conditions. (b) S-plot of OPLS-DA ba The S-plot demonstrates the covariance versus the correlation in conjunction with the var The variables that showed maximum change, and therefore strongly contributed to the cla plot. The variables that did not significantly vary are plotted in the middle. Each point rep Red stars denote the [M–H]À ions of the UK1 species, indicating that the change in the P-limiting treatment. The molecules at the top and bottom are listed in Tables 1 and 2. 2 NATURE COMMUNICATIONS | 4:15 & 2013 Macmillan Publishers Limited. All r Okazaki et al . 2013 PubMedID 23443538
  14. 16.

    Although the pathways are well studied, new compounds/pathways are being

    discovered comprehensive chemical metabolic phenotyping of cells, to investigate lipid remodelling in detail and to identify a new key lipid molecule that has an essential role in protection against P-depletion stress. neutral los conclusion diacyl-3-O reported i a b 20 16 10 2 0 Relative intensity Retention time (min) +P −P P (corr) 4 6 8 12 14 18 –1 1 0 –0 MGDG StGlc GlcCer SQDG PG DGDG Unknown lipid UK1 (GlcADG) PE PI PC Figure 1 | A new lipid inducibly accumulates in Arabidopsis under P depletion. (a) Wild were transferred to either P-sufficient ( þ P, blue line) or P-depleted ( À P, red line) mediu leaves were analysed by HILIC-MS. The total ion current detected by the negative ion mo identified as GlcADG) appeared only under P-limited conditions. (b) S-plot of OPLS-DA ba The S-plot demonstrates the covariance versus the correlation in conjunction with the var The variables that showed maximum change, and therefore strongly contributed to the cla plot. The variables that did not significantly vary are plotted in the middle. Each point rep Red stars denote the [M–H]À ions of the UK1 species, indicating that the change in the P-limiting treatment. The molecules at the top and bottom are listed in Tables 1 and 2. 2 NATURE COMMUNICATIONS | 4:15 & 2013 Macmillan Publishers Limited. All r Glucoronosyldiacylglycerol ters indicate statistically significant differences (Po0.05, Tukey’s test) among the tested genotypes grown under identical growth of letters demonstrates no significant difference among all the tested genotypes for a lipid class. The asterisk denotes ‘not WT sqd1 ugp3-1 sqd2-1 sqd2-2 UGP3 SQD1 SQD2 (SQDG synthase) SQDG GlcADG (1) UDP-SQ UDP-Glc Glc-1-P UDP-GlcA GlcADG synthesis by P depletion SQDG synthesis DAG UDP UDP HO HO HO O O S O S O C O C O OH OH OH O O UDP HO OH HO O O O O O O H OH OH HO O O O O O O H OH OH HO UDP O O OH HO H O O O O UDP OH O O O P OH OH HO OH OH a b Okazaki et al . 2013 PubMedID 23443538
  15. 17.

    Michaud et al . 2016 PubMedID 26898467 Trafficking and Is

    Part of a Large Complex Graphical Abstract Highlights Authors Morgane Michaud, Marianne Tardif, ..., Maryse A. Block, Ju Correspondence morganemichaud7 juliette.jouhet@cea In Brief Mitochondria mem requires exchanges mitochondria and w Michaud et al. iden transmembrane lip containing Mic60 in that Mic60 plays a mitochondria lipid t by acting on memb and contact site. Although the pathways are well studied, new compounds/pathways are being discovered
  16. 18.

    PT B73 CML312 Phosphatidylcholine binds to FT and accelerates flowering

    M G DG PI(4,5)P 2 PS PI PG di18:1-PC PA PE DG DG SQ DG LPE PC LPA LPC 5 µg di18:1-PC di18:1-PE :1-PC At PE At PC 1 µg 0.2 µg NATURE COMMUNICATIONS | DOI: 10.1038/ncomms4553 Nakamura et al . 2014 PubMedID 24698997
  17. 19.

    PT B73 CML312 Phosphatidylcholine binds to FT and accelerates flowering

    M G DG PI(4,5)P 2 PS PI PG di18:1-PC PA PE DG DG SQ DG LPE PC LPA LPC 5 µg di18:1-PC di18:1-PE :1-PC At PE At PC 1 µg 0.2 µg NATURE COMMUNICATIONS | DOI: 10.1038/ncomms4553 120% 100% Relative PECT1 mRNA level 80% 60% 40% * * * * 20% 0% #1 #2 #3 #4 WT * * * * #1 #2 #3 #4 WT 14 12 er 4.0 3.0 PC/PE ratio 2.0 1.0 0.0 ARTICLE were increased. This profile w report on diurnal oscillation o suggesting that the molecular under diurnal regulation. We t PC with different acyl group showed that binding of FT to molecular species in the dar compared with the other mor Supplementary Fig. 5). The wea confirmed at different concent PC molecular species that are p during the dark period, and th these times. To further examin PC species delays flowering, w transgenic line CS8035, wh DESATURASE3 (FAD3) catal PC to 18:3, leading to an inc expected, our data indicated t significantly delayed compare conditions (Fig. 4g), suggest proportion of 18:3-PC delays fl support a model whereby FT species that are predominant flowering at the correct time. Discussion According to the FAC model nuclei of cells in the shoo synthesized at the ER and membrane as well, it is possibl b c d 7 day 9 day 14 day 6.0 5.0 4.0 3.0 2.0 Transcript level of AP1 1.0 0.0 120% 100% 80% 60% Flowering time 40% 20% 0% pFD::amiPECT1 No transgene In pGAS1::FT, ft-10 tsf-1 120% 100% 80% Flowering time 60% 40% 20% 0% In wild type In ft-10 tsf-1 1 2 3 4 7 day 5 6 7 W 9 day 14 day 1 2 3 4 5 6 7 W 1 2 3 4 5 6 7 W pFD:: amiPECT1 No transgene pFD:: amiPECT1 No transgene Figure 3 | Impact of alterations in known flowering time control gen SOC1 (a) and AP1 (b) in pFD::amiPE germination under LD condition. In transgenic lines and wild type as a examined with three biological repl bars. (c) Stable expression of pFD:: the early flowering effect of pFD::am background. (d) Stable expression line (pGAS1::FT, ft-10 tsf-1) further a 16 transgenic plants were averaged Y axes in (c,d) are the number of l control plants that do not harbor th 4 NATURE COMMUNICATIONS | 5:3553 | DOI: 10.1038/ncomms Inducible pOP::amiPECT1 reduces PE synthesis, alters PC/PE ratio reducing flowering time Nakamura et al . 2014 PubMedID 24698997
  18. 20.

    f the lipidome and its association to s suggests that

    it might be used for promising. In addition, the higher a and cross-validated predictions for fl In maize, lipid composition has a high flowering time predictive power re 4 | Whole-lipidome prediction of GCA for dry matter yield, flowering Correlations between individual lipids and GCA values for flowering time Riedelsheimer et al . 2013 PubMedID 23963398
  19. 21.
  20. 25.

    Andosol probability % 0 50 100 Maize had to adapt

    to colder temperatures and soils with low P availability
  21. 26.

    Maize had to adapt to colder temperatures and soils with

    low P availability Andosol probability % 0 50 100
  22. 27.

    TransMexican volcanic belt Maize had to adapt to colder temperatures

    and soils with low P availability Andosol probability % 0 50 100
  23. 28.

    High P Low P High T Low T Pi Recycling

    Cold Adaptation Phospholipids abundance goes down in low P and up in low Temperature Pi recycling Pi recovery e Pi Pi TRENDS in Plant Science of adaptive responses that can be grouped into local and ed at the local level. However, systemic responses involve of phosphatases and Pi recycling through catabolism of of the plant. A better understanding of these mechanisms Lambers et al . 2012 PubMedID 22937909 Degenkolbe et al . 2012 PubMedID 23061922 Phospholipids Sulfolipids Galactolipids Phospholipids Sulfolipids Galactolipids
  24. 29.

    Fst π Hypothesis: phospholipid metabolism was under high selective pressure

    and contributed to maize adaptation to highlands Pi recycling Pi recovery se Pi Pi TRENDS in Plant Science set of adaptive responses that can be grouped into local and olled at the local level. However, systemic responses involve on of phosphatases and Pi recycling through catabolism of s of the plant. A better understanding of these mechanisms 447 A B C D E F
  25. 30.

    Maize adapted twice to highland conditions, Are there any signs

    of convergent evolution? A Lowland Meso America Lowland South America Highland South America Highland Meso America Takuno et al . 2015 PubMedID 23061922
  26. 31.

    Very few genes show signs of convergent highland adaptation between

    Meso America and South America. Only Meso America (0.89 %) Only South America (0.65 %) Meso-America + South America Takuno et al . 2015 PubMedID 23061922
  27. 32.

    Very few genes show signs of convergent highland adaptation between

    Meso America and South America. Only Meso America (0.89 %) Only South America (0.65 %) Meso-America + South America GO terms showing evidence of selection to highlands in both Meso and South America: - Phospholipid biosynthesis - Phosphatidylglycerol biosynthesis - CDP-diacylglycerol biosynthesis - Phosphate utilization in cell wall regeneration - Phosphate acquisition Takuno et al . 2015 PubMedID 23061922
  28. 33.

    Very few genes show signs of convergent highland adaptation between

    Meso America and South America. Only Meso America (0.89 %) Only South America (0.65 %) Meso-America + South America GO terms showing evidence of selection to highlands in both Meso and South America: - Phospholipid biosynthesis - Phosphatidylglycerol biosynthesis - CDP-diacylglycerol biosynthesis - Phosphate utilization in cell wall regeneration - Phosphate acquisition One of the genes showing higher evidence of selection to the highlands is CONSTANS interacting protein 4 Takuno et al . 2015 PubMedID 23061922
  29. 34.

    We use different mapping populations to identify phospholipid metabolic traits

    contributing to highland adaptation • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 15 20 25 30 −120 −110 −100 −90 long lat interaction(Elevation_class) • • Low High Central America • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • −30 −20 −10 0 10 −80 −70 −60 long lat interaction(Elevation_class) • • Low High South America − new lines 3/2/16 Meso-America South-America highland B73 x PT RILS 100 BC1S5 families (25% PT on B73 background) 30 x lowland 30 x highland 30 x lowland 30 x
  30. 35.

    P availability Altitude Mapping populations are grown in common garden

    experiments in highland and lowland conditions Valle de Banderas Pichátaro Metepec
  31. 36.

    P availability Altitude Mapping populations are grown in common garden

    experiments in highland and lowland conditions Valle de Banderas Pichátaro Metepec
  32. 37.

    Samples are then analysed using HPLC-MS to identify and quantify

    glycerolipid species Field sampling: - V4-V6 plants - Youngest fully developed leaf - 600 samples collected in 80 minutes and flash frozen in liquid N2
  33. 38.

    Samples are then analysed using HPLC-MS to identify and quantify

    glycerolipid species Extraction Field sampling: - V4-V6 plants - Youngest fully developed leaf - 600 samples collected in 80 minutes and flash frozen in liquid N2
  34. 39.

    Separation Charged Surface Hybrid Samples are then analysed using HPLC-MS

    to identify and quantify glycerolipid species Extraction Field sampling: - V4-V6 plants - Youngest fully developed leaf - 600 samples collected in 80 minutes and flash frozen in liquid N2
  35. 40.

    Separation Charged Surface Hybrid Agilent 6530 Accurate-Mass Q-TOF LC/MS Exceptional

    MS and MS/MS performance without compr The Agilent 6530 Accurate-Mass Quadrupole Time-of-Flight (Q-T system features Agilent Jet Stream Thermal Focusing technolog icantly improved sensitivity, as well as enhanced MassHunter W software for superior data mining and analysis capabilities. The tures, coupled with Agilent’s True High-Defi nition TOF (True Hi-De nology, enable the 6530 Accurate-Mass Q-TOF to deliver exceptiona excellent mass accuracy, fast data acquisition, and streamlined and quantitative analyses to meet your most challenging research Sensitive, Accurate-Mass MS and MS/MS Analyses The Agilent 6530 Accurate-Mass Q-TOF LC/MS system is designed to provide superior data quality and advanced analytical capabilities for profi ling, iden- tifying, characterizing, and quantifying low molecular-weight compounds and biomolecules with confi dence. Integrat- ing three core Agilent technical inno- vations—True Hi-Def TOF technology, Agilent Jet Stream Thermal Focusing technology and MassHunter Worksta- tion software—the 6530 Q-TOF platform outstanding Q-TOF perform acteristics without any per compromises. • Sub 1-ppm mass accurac confi dence and reduces f • > 20,000 mass resolution target analytes from inte • Up to 5 orders of in-spect range improves detection level targets in the prese abundance compounds • High femtogram sensitivi Agilent 6530 Accurate-Mass Q-TOF LC/MS integrates True Hi-Def TOF technology, Agilent Jet Stream Thermal Focusing technology, and MassHunter Workstation software for sensitive, accurate-mass MS and MS/MS analyses. Detection qTOF MS/MS Samples are then analysed using HPLC-MS to identify and quantify glycerolipid species Extraction Field sampling: - V4-V6 plants - Youngest fully developed leaf - 600 samples collected in 80 minutes and flash frozen in liquid N2
  36. 41.

    Separation Charged Surface Hybrid Agilent 6530 Accurate-Mass Q-TOF LC/MS Exceptional

    MS and MS/MS performance without compr The Agilent 6530 Accurate-Mass Quadrupole Time-of-Flight (Q-T system features Agilent Jet Stream Thermal Focusing technolog icantly improved sensitivity, as well as enhanced MassHunter W software for superior data mining and analysis capabilities. The tures, coupled with Agilent’s True High-Defi nition TOF (True Hi-De nology, enable the 6530 Accurate-Mass Q-TOF to deliver exceptiona excellent mass accuracy, fast data acquisition, and streamlined and quantitative analyses to meet your most challenging research Sensitive, Accurate-Mass MS and MS/MS Analyses The Agilent 6530 Accurate-Mass Q-TOF LC/MS system is designed to provide superior data quality and advanced analytical capabilities for profi ling, iden- tifying, characterizing, and quantifying low molecular-weight compounds and biomolecules with confi dence. Integrat- ing three core Agilent technical inno- vations—True Hi-Def TOF technology, Agilent Jet Stream Thermal Focusing technology and MassHunter Worksta- tion software—the 6530 Q-TOF platform outstanding Q-TOF perform acteristics without any per compromises. • Sub 1-ppm mass accurac confi dence and reduces f • > 20,000 mass resolution target analytes from inte • Up to 5 orders of in-spect range improves detection level targets in the prese abundance compounds • High femtogram sensitivi Agilent 6530 Accurate-Mass Q-TOF LC/MS integrates True Hi-Def TOF technology, Agilent Jet Stream Thermal Focusing technology, and MassHunter Workstation software for sensitive, accurate-mass MS and MS/MS analyses. Detection qTOF MS/MS Identification Quantification Internal Stds LipidBlast Oliver Fiehn, UC Davis Samples are then analysed using HPLC-MS to identify and quantify glycerolipid species Extraction Field sampling: - V4-V6 plants - Youngest fully developed leaf - 600 samples collected in 80 minutes and flash frozen in liquid N2 Kind et al, 2013 PubmedID 25340521
  37. 42.

    Separation Charged Surface Hybrid Agilent 6530 Accurate-Mass Q-TOF LC/MS Exceptional

    MS and MS/MS performance without compr The Agilent 6530 Accurate-Mass Quadrupole Time-of-Flight (Q-T system features Agilent Jet Stream Thermal Focusing technolog icantly improved sensitivity, as well as enhanced MassHunter W software for superior data mining and analysis capabilities. The tures, coupled with Agilent’s True High-Defi nition TOF (True Hi-De nology, enable the 6530 Accurate-Mass Q-TOF to deliver exceptiona excellent mass accuracy, fast data acquisition, and streamlined and quantitative analyses to meet your most challenging research Sensitive, Accurate-Mass MS and MS/MS Analyses The Agilent 6530 Accurate-Mass Q-TOF LC/MS system is designed to provide superior data quality and advanced analytical capabilities for profi ling, iden- tifying, characterizing, and quantifying low molecular-weight compounds and biomolecules with confi dence. Integrat- ing three core Agilent technical inno- vations—True Hi-Def TOF technology, Agilent Jet Stream Thermal Focusing technology and MassHunter Worksta- tion software—the 6530 Q-TOF platform outstanding Q-TOF perform acteristics without any per compromises. • Sub 1-ppm mass accurac confi dence and reduces f • > 20,000 mass resolution target analytes from inte • Up to 5 orders of in-spect range improves detection level targets in the prese abundance compounds • High femtogram sensitivi Agilent 6530 Accurate-Mass Q-TOF LC/MS integrates True Hi-Def TOF technology, Agilent Jet Stream Thermal Focusing technology, and MassHunter Workstation software for sensitive, accurate-mass MS and MS/MS analyses. Detection qTOF MS/MS Identification Quantification Internal Stds LipidBlast Samples are then analysed using HPLC-MS to identify and quantify glycerolipid species Extraction Kind et al, 2013 PubmedID 25340521
  38. 43.

    A B C D E F Metabolite ratios can be

    used to improve our ability to find associations between metabolite concentrations and genetic loci A, B, C… D B B C , i=B E ∑i i=B F ∑i Petersen et al, 2012 PubmedID 25340521 Metabolite concentrations: Sums of metabolite concentrations: Ratios of metabolite concentrations: Ratios of metabolite sums: i=B E ∑i i=B F ∑i
  39. 44.

    A B C D E F Metabolite ratios can be

    used to improve our ability to find associations between metabolite concentrations and genetic loci A, B, C… D B B C , i=B E ∑i i=B F ∑i concentrations a der. It is therefore os in the tests for b)= -log(b/a) this Moreover, in many metabolite ratios a log-normal dis- or instance, a test 2] showed that in ratio distribution normal distribu- e used. measure whether gnificantly stron- longing metabol- ‘p-value(M1 | X)’, orresponding to a in a GWAS this a SNP and in an nd the metabolite Conservative critical p-gain values for common statistics Although the p-gain is now frequently used in MWAS and in GWAS with metabolic traits, only a rule of thumb for the determination of critical values has been applied so far. The p-gain was considered as being sig- nificant when its value exceeded the number of analyzed metabolite concentrations, that is, the number of add- itionally performed tests [11–13]. Here we derive critical values of the p-gain by determination of the distribution to define a more sensible threshold. As the distribution of the p-gain depends on the correlation structure among the metabolites, conservative critical values are beneficial in case of analyzing multiple sets of metabo- lites, since they can be applied to all analyzed settings. For this purpose, we use a universal p-gain defined as the ratio of p-values belonging to two uncorrelated metabolites: p-gain M1 M2 jX   : ¼ p-value M1 ð jXÞ p-value M1=M2 ð jXÞ ; cor M1; M1=M2 ð Þ ¼ 0 ð2Þ Petersen et al, 2012 PubmedID 25340521 Metabolite concentrations: Sums of metabolite concentrations: Ratios of metabolite concentrations: Ratios of metabolite sums: i=B E ∑i i=B F ∑i
  40. 45.

    PT B73 CML312 Highland maize has a higher Shoot/Root ratio

    Local response Root system Lateral root formation and growth Root hair formation architecture Pi re Pi transport Primary root growth inhibition Pi recovery Systemic response Phosphate homeostasis sensing Pi Pi Pi P TRENDS in Plant Figure 2. Local and systemic responses. Sensing of phosphate (Pi) by the model plant Arabidopsis triggers a set of adaptive resp ystemic (long distance) responses. This review focuses on developmental adaptations that are mainly controlled at the local lev ncreased Pi transport through expression of high-affinity transporters, intense Pi recovery through secretion of phosphatase
  41. 46.

    PT B73 CML312 Highland maize has a higher Shoot/Root ratio

    Local response Root system Lateral root formation and growth Root hair formation architecture Pi re Pi transport Primary root growth inhibition Pi recovery Systemic response Phosphate homeostasis sensing Pi Pi Pi P TRENDS in Plant Figure 2. Local and systemic responses. Sensing of phosphate (Pi) by the model plant Arabidopsis triggers a set of adaptive resp ystemic (long distance) responses. This review focuses on developmental adaptations that are mainly controlled at the local lev ncreased Pi transport through expression of high-affinity transporters, intense Pi recovery through secretion of phosphatase
  42. 47.

    PT B73 CML312 Highland maize has a higher Shoot/Root ratio

    Local response Root system Lateral root formation and growth Root hair formation architecture Pi re Pi transport Primary root growth inhibition Pi recovery Systemic response Phosphate homeostasis sensing Pi Pi Pi P TRENDS in Plant Figure 2. Local and systemic responses. Sensing of phosphate (Pi) by the model plant Arabidopsis triggers a set of adaptive resp ystemic (long distance) responses. This review focuses on developmental adaptations that are mainly controlled at the local lev ncreased Pi transport through expression of high-affinity transporters, intense Pi recovery through secretion of phosphatase
  43. 48.

    Highland maize has a higher Shoot/Root ratio PT B73 Meso

    America South America Wilcox test p_val < 0.01
  44. 49.

    We are currently quantifying growth rates using an aeroponic system

    High P Low P Guillaume Lobet Xavier Draye High P Low P low temp high temp 500 plants x block
  45. 53.

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    Plant Phenomics: Data Integration & Analyses Call for papers Guest

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