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Comparative analyses of the potato Comparative analyses of the potato and tomato transcriptomesand tomato transcriptomes
David Francis, AllenDavid Francis, AllenVan DeynzeVan Deynze, John Hamilton, , John Hamilton, Walter De Jong, David Douches, Sanwen Huang, Walter De Jong, David Douches, Sanwen Huang, and C. and C. Robin BuellRobin Buell
Supported by the AFRI Plant Breeding, Genetics, and Supported by the AFRI Plant Breeding, Genetics, and Genomics Program of USDA’s National Institute of Food and Genomics Program of USDA’s National Institute of Food and
AgricultureAgriculture
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Questions
International Sol Project: How can a common set of genes/proteins give rise to such a wide range of morphologically and ecologically distinct organisms?
SolCAP: How can variation be harnessed to improve varieties that benefit the consumer, processors, and the environment?
Sequence data available to address these questions:
S. phureja draft genome sequence
S. tuberosum, S. lycopersicum, S. pimpinellifolium GAII transcriptomes
Technology
Next Generation Sequencing
SNP genotyping
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What comparisons do we want to make?
How well do S. tuberosum expressed sequences align to S. phureja genomic sequences?
How well do S. lycopersicum expressed sequences align to S. phureja genomic sequences?
How is variation distributed within a Species?
within a market class?
within a variety?
within a gene?
Which sequence variation is important to phenotypic variation?
Library creation/QC GAII sequencing (single and paired end)
Data Collection Assembly
400
300
Analysis:transcriptome complexitySNP calling/validation
identification of genes under selection
Sample Total ClustersTotal PE Reads
PF Passed Clusters
% PF Passed Clusters
Total PE PF Reads
Actual PE Reads
Atlantic 1 7,601,277 15,202,554 6,382,748 83.97 12,765,496
Atlantic 2 10,544,542 21,089,084 9,252,168 87.74 18,504,336 30,185,186
Premier 1 7,812,394 15,624,788 6,652,121 85.15 13,304,242
Premier 2 11,678,379 23,356,758 9,999,926 85.63 19,999,852 31,949,096
Snowden 1 7,996,418 15,992,836 6,837,553 85.51 13,675,106
Snowden 2 11,781,671 23,563,342 10,393,322 88.22 20,786,644 33,288,120
Illumina GA II Output for Potato
Velvet Assemblies of Potato Illumina Sequences
• With a minimum kmer of 31 and a minimum contig length of 150bp:
Variety Total GbTranscriptome
Size (Mb)No.
Contigs N50 (bp)Maximum
Contig (Kb)
Atlantic 1.8 38.4 45215 666 11.2
Premier 1.9 38.2 54917 408 6.6
Snowden 2.0 38.2 58754 358 6.9
Velvet Assemblies of Potato Illumina Sequences
• Atlantic:• 45214 contigs• 32520 align with GMAP(95%id, 50%cov)• 27106 align with GMAP(95%id, 90%cov)
• Premier:• 54917 contigs• 41497 align with GMAP (95%id, 50%cov)• 37297 align with GMAP (95%id, 90%cov)
• Snowden:• 58754 contigs• 44479 align with GMAP (95%id, 50%cov)• 40708 align with GMAP (95%id, 90%cov)
Alignment of the S. tuberosum GAII-transcriptome contigs to the PGSC draft genome sequence from S. phureja :
Tomato Illumina GA II Output
VarietyInsert Size
Read Length Total Reads PF Reads %PF Passed Total PF
FL7600 300 61/47 22,491,304 20,685,342 92.0FL7600 300 60 16,025,976 14,382,577 89.8FL7600 300 60 15,645,164 13,985,875 89.4 49,053,794
NC84173 350 61/61 27,079,946 22,687,626 83.8NC84173 350 60 11,058,431 10,366,811 93.8NC84173 350 60 14,401,240 12,687,134 88.1 52,539,617OH9242 350 61/47 26,960,898 24,874,218 92.3OH9242 350 60 10,316,775 9,671,753 93.8OH9242 350 60 14,676,814 12,879,812 87.8 51,954,487
T5 350 61/47 26,799,944 24,677,302 92.1T5 350 60 16,822,639 14,738,351 87.6T5 350 60 15,726,257 13,744,511 87.4 59,348,840
PI114490 350 61/47 17,721,226 16,422,842 92.7PI114490 350 60 17,115,349 14,902,672 87.1PI114490 350 60 17,890,649 15,248,587 85.2 52,727,224PI212816 350 61/47 17,631,906 16,450,422 93.3PI212816 350 60 18,238,179 15,354,882 84.2PI212816 350 84 21,829,622 18,500,235 84.8 57,699,707
Variety Total GbTranscriptome
Size (Mb)No.
Contigs N50 (bp)Maximum
Contig (Kb)
FL7600 2.82 39.8 59,581 424 12.1
NC84173 2.77 39.2 60,534 496 13.3
OH9242 2.70 39.1 59,051 476 11.6
T5 3.04 40.6 60,031 632 14
PI114490 2.70 41 61,310 690 11.7
PI212816 3.00 41.1 66,118 471 14
Velvet Assemblies of TomatoIllumina Sequences
• With a k-mer length of 31 and a minimum contig length of 150bp:
Sequence quality: Viewing an Atlantic potato contig from the Velvet assembly
FL7600 (93.7 % id; 94.4 % coverage)
Snowden (97.9; 94.7)
Alignment of contigs relative to S. phureja
Query SNPs Filtered SNPs
Atlantic Asm 224748 150669
Premier Asm 265673 181800
Snowden Asm 258872 166253
Identify intra-varietal SNPs
A/C SNP
Filtered SNP counts
Ref Query d 10 d 20 d 30 d 40 d 50 d 60 d 100
atlantic atlantic 21336 17509 14493 12150 10277 8673 4435
atlantic premier 21789 18050 15084 12477 10584 8919 4620
atlantic snowden 19997 16518 13694 11378 9689 8048 4173
premier atlantic 21117 17096 14106 11785 9790 8222 4228
premier premier 22951 18431 15016 12377 10300 8703 4371
premier snowden 20972 16846 13709 11357 9479 7873 4113
snowden atlantic 20777 16998 13984 11619 9647 8131 4186
snowden premier 22101 17888 14701 12068 10124 8650 4223
snowden snowden 21083 16963 13792 11218 9359 7735 3896
Filtering on SNP quality and 1 SNP/ 150bp window
Genotyping platforms….
Comments on quality control…
Data….
direct comparison of sequence
analysis of SNPs across populations
COS
R-gene
Comparison of two genes on tomato chromosome 9 BAC
COSII
Fresh Market vs Fresh Market Identities = 573/573 (100%), Gaps = 0/573 (0%)Fresh Market vs Processing Identities = 569/569 (100%), Gaps = 0/569 (0%)S. lycopersicum vs S. pimpinellifolium Identities = 339/341 (99%), Gaps = 0/341 (0%)Potato vs Potato Identities = 606/612 (99%), Gaps = 0/612 (0%)Tomato vs Potato Identities = 914/948 (96%), Gaps = 6/948 (0%)
DIVERGED SEQUENCE
Fresh Market vs Fresh Market Identities = 959/959 (100%), Gaps = 0/959 (0%)Fresh Market vs Processing Identities=1560/1560(100%), Gaps=0/1560 (0%)S. lycopersicum vs S. pimpinellifolium Identities = 612/613 (99%), Gaps = 0/613 (0%)Tomato vs Potato Identities = 223/280 (79%), Gaps = 11/280 (3%)Potato vs Potato Identities = 246/278 (88%), Gaps = 7/278 (2%)
What patterns do we expect to see for genes “under selection”?•Low Variation (fixed)•High Ka/Ks (mutations affect protein, possible diversifying selection)•Mutations (loss of function)•FST (genes that distinguish populations)
All 173 markers (K=6)
89 Coding markers (K=5)
84 Non-coding markers (K=6)
Processing Fresh-market Vintage Landrace
500K burnin/750K MCMC reps, 20 runs for each K from 3 to 8
Population structure: coding vs. non-coding
CA & OH OH
CA OH OH
CN
CN
Distribution of FST for genes
ovate: 0fw2.2: 0sp6: 0.14
ovate: 0.26fw2.2: 0sp6: 0.73
ovate: 0.31fw2.2: 0sp6: 0.47
ovate: 0fw2.2: 0.5sp6: 1
ovate: 0fw2.2: 0.42sp6: 0.74
ovate: 0.14fw2.2: 0.46sp6: 0.05
Marker Chrom SourceNo. of SNPs
LEOH14 unknown EST542533 2 Pathogenesis-related leaf protein LEOH16 5 EST301659 4 drought-induced protein LEOH17 multiple EST551464 5 putative alcohol dehydrogenaseLEOH20 unknown EST327354 2 ultraviolet-B-repressible protein LEOH23 2 EST546919 3 Vesicle-associated membrane LEOH25 9 EST511738 3 gamma hydroxybutyrate LEOH29 unknown EST243853 2 A96510 protein F27F5.25 LEOH31 9 EST583372 10 chlorophyll synthetase G4 LEOH32 9 EST358606 2 acetyl-CoA C-acyltransferase LEOH33 9 EST471439 5 endo-1,3-1,4-beta-D-glucanaseLEOH34 9 EST435427 6 tuberisation-related proteinLEOH35 9 EST549543 8 photosystem II protein W CosOH7 2 TOVBN23 5 putative MYB transcription factorLEVCOH11 1 AJ785180. 2 late embryogenesis (Lea)-like
Examples of highly polymorphic genes within S. lycopersicum
0.304 Associated with introgression0.043 Duplicated genes0.087 Ethylene induced0.174 Pathogen induced0.130 Abiotic Stress induced
Note: I am working on a replacement that compares Ka/Ks for selected tomato and potato genes
Marker Chrom SourceNo. of SNPs
LEOH14 unknown EST542533 2 Pathogenesis-related leaf protein LEOH16 5 EST301659 4 drought-induced protein LEOH17 multiple EST551464 5 putative alcohol dehydrogenaseLEOH20 unknown EST327354 2 ultraviolet-B-repressible protein LEOH23 2 EST546919 3 Vesicle-associated membrane LEOH25 9 EST511738 3 gamma hydroxybutyrate LEOH29 unknown EST243853 2 A96510 protein F27F5.25 LEOH31 9 EST583372 10 chlorophyll synthetase G4 LEOH32 9 EST358606 2 acetyl-CoA C-acyltransferase LEOH33 9 EST471439 5 endo-1,3-1,4-beta-D-glucanaseLEOH34 9 EST435427 6 tuberisation-related proteinLEOH35 9 EST549543 8 photosystem II protein W CosOH7 2 TOVBN23 5 putative MYB transcription factorLEVCOH11 1 AJ785180. 2 late embryogenesis (Lea)-like
Examples of highly polymorphic genes within S. lycopersicum
non-synonymous 0.53synonymous 0.37non-coding 0.09
Note: I am working on a replacement that compares Ka/Ks for selected tomato and potato genes
2 3 11 127 8 9 105 641
2
3
4
5
6
7
8
9
<0.001
<0.0001
Combined
12
1
10
11
r 2 value
Chr
omso
me
P v
alue
>0.05
<0.05
<0.01
0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.000.70 0.80 0.90 1.000.00 0.10 0.20 0.30 0.40 0.50 0.60
12
r 2 value
6 7 8 9 10 11
10
<0.000111
12
1 2 3 4 5
4
<0.01
5
6
<0.0017
8
9
Fresh Market
Chr
omso
me
1
P v
alue
>0.05
2
<0.053
Processing Fresh Market Vintage Wild
Distribution of PM genes across populations is not random
Conclusions~5.7 Gb PF potato transcriptome sequence (3 varieties)
~14.3 Gb PF tomato transcriptome sequence (6 varieties)
S. phureja draft genome is an excellent scaffold for potato and tomato GAII transcriptome alignments
SNPs are not evenly distributed in genes
Genes with signatures of selection (Ka/Ks; high FST) tend to be genes associated with response to abiotic and biotic stress.
Breeders have selected for groups of genes suggesting that co-adapted complexes
Acknowledgments
Collaborators, OSUMatt Robbins
Sung-Chur SimTroy Aldrich
Collaborators, CornellWalter de JongLucas MuellerJoyce van Eck
Collaborators, CAUWencai Yang
Collaborators, CAASSanwen Huang
Collaborators, UCDAllen Van Deynze
Kevin StoffelAlex Kozic
FundingUSDA/AFRI
Collaborators, MSUDavid DouchesC Robin BuellJohn Hamilton
Kelly Zarka