low molecular weight glutenin subunits and gliadins in 137 double haploid wheat lines derived from a...
DESCRIPTION
International Gluten Workshop, 11th; Beijing (China); 12-15 Aug 2012TRANSCRIPT
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M.T. LABUSCHAGNE and A. VAN BILJON
Department of Plant
Sciences, University of the Free State, P.O. Box
339, Bloemfontein 9300, South Africa
Email: [email protected]
LOW MOLECULAR WEIGHT GLUTENIN SUBUNITS
AND GLIADINS IN 137 DOUBLE HAPLOID WHEAT LINES DERIVED FROM A
CROSS BETWEEN KARIEGA AND AVOCET
INTRODUCTION
the protein of maize is deficient in two essential amino acids, lysine and tryptophan
They are controlled by Gli loci on the short arms of chromosomes 1 and 6
γ and ω = 1A, 1B, 1D Gli-A1, Gli-B1, Gli-D1 α and β = group 6 chromosomes, Gli-A2, Gli-B2, Gli-D2
Wheat gliadins are a highly polymorphic group of seed storage proteins
From Shewry and Lookhart (2003)
Gliadin extract gives ω5, ω1,2, α and γ gliadins
Glutenin extract gives glutenin bound ω extracts and HMW and LMW subunits
Genes encoding LMW GS (Glu-3) are linked to genes (Gli-1) encoding ω and γ gliadins
Most wheat cultivars show similar overall patterns of gliadin and glutenin subunits with characteristic regions for
each type
AIM OF THE STUDY
To study low molecular weight glutenins and gliadins in a DH population of a cross between Kariega and Avocet
A
AIM OF STUDY
To study low molecular weight
glutenins and gliadins in a DH population of a cross between
Kariega and Avocet
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Materials and methods
Double haploid wheat population, developed with wheat x maize crosses using wheat x maize crosses
Avocet x Kariega: 137 DH’s developed from F2 material
Kariega = hard red South African bread wheat with excellent quality
Avocet = standard white Australian spring wheat
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Materials and methods
Protein extraction for RP-HPLC using method of Wieser et al. (1998)
First gliadin extraction with 70% ethanol
RP-HPLC with C18 column
Glutenin extraction with 50% propan-1-ol, urea and DTT and 4-
vinylpyridine
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Results
Gliadin profile of Avocet
Gliadin profile of Kariega
ωωω ωωα ωωγ
ωωω ωωα ωωγ
GLIADIN PEAK AREA (%) OF PARENTS AND THE DH POPULATION
Name P20.8 P21.4 P22.3 P23 p24 p25.1 p26 p265 p27 p275 p28.6 p31 p345 p36
Avocet 2.91 6.13 0.00 0.00 2.4 0.00 13.12 10.35 4.25 8.00 2.66 18.47 6.89 1.27
Kariega 3.99 3.63 1.94 1.3 2.3 2.65 8.67 7.89 4.02 7.49 0.00 18.49 5.03 1.33
DH 3.44 3.86 1.28 1.77 2.36 0.900 13.16 11.29 5.13 6.69 2.59 16.57 6.77 1.74
ω α γ
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Gliadins
ω peak 22.3 was absent in Avocet but was present in 50 of 137 DH’s
ω peak 23 was absent in Avocet but was present in 127 of 137 DH’s
α peak 25.1 was absent in Avocet, but was present in only 41 of 137 DH’s
8/14/2012
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Gliadins
8/14/2012
α peak 28.6 was absent in Kariega, but was present in 118 of 137 DH’s
α peak 26 was much higher in Avocet (13.12) than in Kariega (8.67) but the DH average was 13.16, like the Avocet parent
α peak 26.5 was higher for the DH average (11.29) than either parent Avocet (10.35) and Kariega (7.89)
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Gliadins
8/14/2012
α peak 27.5 was lower for the DH average (6.69) than for either parent Avocet (8) or Kariega (7.49)
The other peaks for DH averages were close to the average of the two parents
Highly significant (P≤0.0001) correlations between gliadins
Characteristic1 Characteristic2 Correlation
P20.8 (ω) P21.4(ω) -0.693
P20.8(ω) P22.3(ω) -0.432
P21.4 (ω) P22.3 (ω) 0.872
P22.3 (ω) P24 (α) 0.376
P22.3 (ω) P31 (α) -0.376
P23 (α) P36 (γ) 0.346
P25.1 (α) P26 (α) -0.886
P27.5 (α) P28.6 (α) -0.685
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Avocet glutenins
HMW HM H
HMW HMW
Kariega glutenins
HMW glutenins LMW glutenins
LMW glutenins HMW glutenins
0, 7+8, 2+12
2*, 17+18, 2+12
LMW GLUTENIN PEAKS (% AREA) OF PARENTS AND THE DH POPULATION
gl26 gl27 gl28.5 gl28.8 gl29.4 gl30 gl32 gl33.3 Avocet 6.72 37.05 5.17 3.63 3.60 6.06 3.22 4.03 Kariega 5.96 33.40 4.90 3.46 3.71 5.93 3.18 2.34 DH 9.79 28.97 4.24 4.03 3.34 5.34 3.98 5.41
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LMW glutenins
8/14/2012
These subunits were more difficult to score than the gliadins
Peak 26 average of the DH was much higher (9.79) than that of either Avocet (6.72) or Kariega (5.96)
Peak 27 average of the DH was much lower (28.97) than either Avocet (37.05) or Kariega (33.4)
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LMW glutenins
8/14/2012
Peak 33.3 DH average (5.41) was much higher than that of either Avocet (4.03) or Kariega (2.34)
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Characteristic1 Characteristic2 Correlation
Peak 26 Peak 27 -0.372
Peak 28.8 Peak 29.4 -0.318
Peak 28.8 Peak28.5 0.243
Peak 28.5 Peak 29.4 -0.248
Peak 29.4 Peak 28.8 -0.318
Peak 28.8 Peak 30 -0.274
Highly significant (P≤0.01) correlations between LMW glutenins
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Characteristic1 Characteristic2 Correlation
Gliadin peak 26.5 Glutenin peak 27 -0.229
Gliadin peak 27.5 Glutenin peak 28.5 0.253
Gliadin peak 25.1 Glutenin peak 28.5 -0.273
Gliadin peak 34.5 Glutenin peak 33 0.419
Highly significant (P≤0.01) correlations between LMW glutenins and gliadins
8/14/2012
DISCUSSION AND CONCLUSIONS
Peak 22.3 absent in Avocet was present in 36% of the DH population
Peak 23 absent in Avocet was present in 93% of DH population
For the gliadins three peaks were absent in Avocet which were in Kariega, and one was absent in Kariega which was present in Avocet
Peak 28.6 absent in Kariega was present in 86% of the DH population
Peak 25.1 absent in Avocet was present in 30% of DH population
Peaks 25.1 and 26 were highly negatively correlated (-0.886) indicating that the presence of one lead to the supression of
the other
Peaks 20.8 and 21.4; and 27.5 and 28.6 were also highly negatively correlated (-0.693 and -0.685) indicating that the
presence of one usually supressed the expression of the other
Peak 21.4 and 22.3 almost always occurred together and were correlated r=0.872
In four of the peaks the values were higher for the DH population than that of either parent, and for the four other
peaks they were lower than for either parent
There were some significant correlations within the LMW glutenins and between LMW glutenins and the gliadins, but
the values were very low
Eight clear LMW glutenin peaks were seen in all material
The DH population expressed the peak missing in either parent to a much higher extent than expected in two cases and much
lower than expected in two cases. One can speculate on the reason for this
Both the glutenin and the gliadin peaks of the DH population were not intermediate between that of the parents, indicating some interaction between genes coding for these loci
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