SE136:/MS2

Sample Set Information

ID	TSE1237
Title	Deciphering starch quality of rice kernels using metabolite profiling and pedigree network analysis.
Description	The physiological properties of rice grains are immediately obvious to consumers. High-coverage metabolomic characterization of the rice diversity research set predicted a negative correlation between fatty acid and lipid levels and amylose/total starch ratio (amylose ratio), but the reason for this is unclear. To obtain new insight into the relationships among the visual phenotypes of rice kernels, starch granule structures, amylose ratios, and metabolite changes, we investigated the metabolite changes of five Japonica cultivars with various amylose ratios and two knockout mutants (e1, a Starch synthase IIIa (SSIIIa)-deficient mutant and the SSIIIa/starch branching enzyme (BE) double-knockout mutant 4019) by using mass spectrometry-based metabolomics techniques. Scanning electron microscopy clearly showed that the two mutants had unusual starch granule structures. The metabolomic compositions of two cultivars with high amylose ratios (Hoshiyutaka and Yumetoiro) exhibited similar patterns, while that of the double-knockout mutant, which has an extremely high amylose ratio, differed. Rice pedigree network analysis of the cultivars and the mutants provided insight into the association between metabolic-trait properties and their underlying genetic basis in rice breeding in Japan. Multidimensional scaling analysis revealed that the Hoshiyutaka and Yumetoiro cultivars were Indica-like, yet they are classified as Japonica subpopulations. Exploring metabolomic traits is a powerful way to follow rice genetic traces and breeding history.
Authors	Kusano M, Fukushima A, Fujita N, Okazaki Y, Kobayashi M, Oitome NF, Ebana K, Saito K.
Reference	Mol Plant. 2012 Mar;5(2):442-51. doi: 10.1093/mp/ssr101. Epub 2011 Dec 15.
Comment

PubMed

Analytical Method Details Information

ID	MS2
Title	LC-IT-TOF-MS
Instrument	(LC, Shimadzu LC-20AD system; MS, Shimadzu LCMS-IT-TOF)
Instrument Type
Ionization	ESI
Ion Mode
Description	Extraction for IT-MS Each Sample (50 mg) was extracted with 750 μl of chloroform/MeOH(1:1, v/v) containing 1.25μM 1,2-dioctanoyl-sn-glycero-3-phosphocholine (SIGMA) followed by centrifugation at 10,000g at 4°C for 5 min. The supernatant was transferred to a 2ml tube, and the extraction procedure was repeated again. The combined supernatant was evaporated to dryness by SPD2010 SpeedVac® concentrator. The residue was dissolved in 750μl of ethanol, and centrifuged at 10,000g at 4°C for 5 min. Six hundred microlitter of the supernatant was transferred to a glass tube for polar-lipid analysis. LC-IT-TOF-MS conditions Extracts (0.5μl, ca. 33.3μg of each sample) was analyzed by LC-MS with ESI interface (LC, Shimadzu LC-20AD system; MS, Shimadzu LCMS-IT-TOF) operated by Shimadzu LCMSsolution software (version 3.60). Two-solvent system was used for separation of each metabolite. The analytical conditions were as follows. Column, Shim-pack XR-ODS (2.0 mm I.D., 50 mm long); solvent A, water (1% 1M ammonium formate and 0.1% formic acid); solvent B, acetonitrile/isopropyl alcohol (40:60, v/v. 1% 1M ammonium formate and 0.1% formic acid);gradient program, 40% B at 0 min, 75% B at 3 min, 95% B at 10 min, 100% B at 19 min, 100% B at 27 min, 40% B at 27.01 min (total run time, 30 min); flow rate, 0.3 ml/min; column temperature, 55°C; MS interface voltage, 4.50 kV, nebulizer gas, 1.50 L/min; CDL temperature 200.0℃, heat block temperature, 200°C; detection mode, scan (m/z 150 ̃1600, positive); scan time, 0.25 sec; ion accumulation time, 20 msec.
Comment_of_details	Redestig et al. BMC Syst Biol. 2011 Oct 28;5:176.

PubMed