Georgios Joannis Pappas Jr

Dr. Georgios Joannis Pappas Jr

orcid

Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 June 2014 in Nature
Verified
Journal Article
Open access
AMAlexander A. Myburg
Alexander A. Myburg
DGDario Grattapaglia
Dario Grattapaglia
GTGerald A. Tuskan
Gerald A. Tuskan
UHUffe Hellsten
Uffe Hellsten
RHRichard D. Hayes
Richard D. Hayes
JSJeremy Schmutz
Jeremy Schmutz
Eucalypts are the world's most widely planted hardwood trees. Their outstanding diversity, adaptability and growth have made them a global renewable resource of fibre and energy. We sequenced and assembled >94% of the 640-megabase genome of Eucalyptus grandis. Of 36,376 predicted protein-coding genes, 34% occur in tandem duplications, the largest proportion thus far in plant genomes. Eucalyptus also shows the highest diversity of genes for specialized metabolites such as terpenes that act as chemical defence and provide unique pharmaceutical oils. Genome sequencing of the E. grandis sister species E. globulus and a set of inbred E. grandis tree genomes reveals dynamic genome evolution and hotspots of inbreeding depression. The E. grandis genome is the first reference for the eudicot order Myrtales and is placed here sister to the eurosids. This resource expands our understanding of the unique biology of large woody perennials and provides a powerful tool to accelerate comparative biology, breeding and biotechnology.

30 June 2008 in BMC Genomics
Verified
Journal Article
Open access
PDF file
ENEvandro Novaes
Evandro Novaes
DDDerek R Drost
Derek R Drost
WFWilliam G Farmerie
William G Farmerie
GJGeorgios Joannis Pappas Jr
Georgios Joannis Pappas Jr
DGDario Grattapaglia
Dario Grattapaglia
MKMatias Kirst
Matias Kirst
Background: Benefits from high-throughput sequencing using 454 pyrosequencing technology may be most apparent for species with high societal or economic value but few genomic resources. Rapid means of gene sequence and SNP discovery using this novel sequencing technology provide a set of baseline tools for genome-level research. However, it is questionable how effective the sequencing of large numbers of short reads for species with essentially no prior gene sequence information will support contig assemblies and sequence annotation. Results: With the purpose of generating the first broad survey of gene sequences in Eucalyptus grandis, the most widely planted hardwood tree species, we used 454 technology to sequence and assemble 148 Mbp of expressed sequences (EST). EST sequences were generated from a normalized cDNA pool comprised of multiple tissues and genotypes, promoting discovery of homologues to almost half of Arabidopsis genes, and a comprehensive survey of allelic variation in the transcriptome. By aligning the sequencing reads from multiple genotypes we detected 23,742 SNPs, 83% of which were validated in a sample. Genome-wide nucleotide diversity was estimated for 2,392 contigs using a modified theta (θ) parameter, adapted for measuring genetic diversity from polymorphisms detected by randomly sequencing a multi-genotype cDNA pool. Diversity estimates in non-synonymous nucleotides were on average 4x smaller than in synonymous, suggesting purifying selection. Non-synonymous to synonymous substitutions (Ka/Ks) among 2,001 contigs averaged 0.30 and was skewed to the right, further supporting that most genes are under purifying selection. Comparison of these estimates among contigs identified major functional classes of genes under purifying and diversifying selection in agreement with previous researches. Conclusion: In providing an abundance of foundational transcript sequences where limited prior genomic information existed, this work created part of the foundation for the annotation of the E. grandis genome that is being sequenced by the US Department of Energy. In addition we demonstrated that SNPs sampled in large-scale with 454 pyrosequencing can be used to detect evolutionary signatures among genes, providing one of the first genome-wide assessments of nucleotide diversity and Ka/Ks for a non-model plant species.

6 February 2012 in New Phytologist
Verified
Journal Article
Closed access
PDF file
MRMarcos D. V. Resende
Marcos D. V. Resende
MRMárcio F. R. Resende
Márcio F. R. Resende
CSCarolina P. Sansaloni
Carolina P. Sansaloni
CPCesar D. Petroli
Cesar D. Petroli
AMAlexandre A. Missiaggia
Alexandre A. Missiaggia
DGDario Grattapaglia
Dario Grattapaglia

25 February 2016 in Genome Biology
Verified
Journal Article
Open access
PDF file
AVAnna Vlasova
Anna Vlasova
SCSalvador Capella-Gutiérrez
Salvador Capella-Gutiérrez
MRMartha Rendón-Anaya
Martha Rendón-Anaya
MOMiguel Ángel Hernández Oñate
Miguel Ángel Hernández Oñate
AMAndré E. Minoche
André E. Minoche
Roderic Guigó SerraRoderic Guigó Serra
Roderic Guigó Serra
Legumes are the third largest family of angiosperms and the second most important crop class. Legume genomes have been shaped by extensive large-scale gene duplications, including an approximately 58 million year old whole genome duplication shared by most crop legumes. We report the genome and the transcription atlas of coding and non-coding genes of a Mesoamerican genotype of common bean (Phaseolus vulgaris L., BAT93). Using a comprehensive phylogenomics analysis, we assessed the past and recent evolution of common bean, and traced the diversification of patterns of gene expression following duplication. We find that successive rounds of gene duplications in legumes have shaped tissue and developmental expression, leading to increased levels of specialization in larger gene families. We also find that many long non-coding RNAs are preferentially expressed in germ-line-related tissues (pods and seeds), suggesting that they play a significant role in fruit development. Our results also suggest that most bean-specific gene family expansions, including resistance gene clusters, predate the split of the Mesoamerican and Andean gene pools. The genome and transcriptome data herein generated for a Mesoamerican genotype represent a counterpart to the genomic resources already available for the Andean gene pool. Altogether, this information will allow the genetic dissection of the characters involved in the domestication and adaptation of the crop, and their further implementation in breeding strategies for this important crop.

25 May 2018 in Nucleic Acids Research
Verified
Journal Article
Open access
PDF file
RHRafael Hernández-De-Diego
Rafael Hernández-De-Diego
STSonia Tarazona
Sonia Tarazona
CMCarlos Martínez-Mira
Carlos Martínez-Mira
LBLeandro Balzano-Nogueira
Leandro Balzano-Nogueira
PFPedro Furió-Tarí
Pedro Furió-Tarí
Ana ConesaAna Conesa
Ana Conesa
The increasing availability of multi-omic platforms poses new challenges to data analysis. Joint visualization of multi-omics data is instrumental in better understanding interconnections across molecular layers and in fully utilizing the multi-omic resources available to make biological discoveries. We present here PaintOmics 3, a web-based resource for the integrated visualization of multiple omic data types onto KEGG pathway diagrams. PaintOmics 3 combines server-end capabilities for data analysis with the potential of modern web resources for data visualization, providing researchers with a powerful framework for interactive exploration of their multi-omics information. Unlike other visualization tools, PaintOmics 3 covers a comprehensive pathway analysis workflow, including automatic feature name/identifier conversion, multi-layered feature matching, pathway enrichment, network analysis, interactive heatmaps, trend charts, and more. It accepts a wide variety of omic types, including transcriptomics, proteomics and metabolomics, as well as region-based approaches such as ATAC-seq or ChIP-seq data. The tool is freely available at www.paintomics.org

30 January 2008 in BMC Genomics
Verified
Journal Article
Open access
PDF file
MLMagali Lescot
Magali Lescot
PPPietro Piffanelli
Pietro Piffanelli
ACAna Y Ciampi
Ana Y Ciampi
MRManuel Ruiz
Manuel Ruiz
GBGuillaume Blanc
Guillaume Blanc
CTChristopher D Town
Christopher D Town
Musa species (Zingiberaceae, Zingiberales) including bananas and plantains are collectively the fourth most important crop in developing countries. Knowledge concerning Musa genome structure and the origin of distinct cultivars has greatly increased over the last few years. Until now, however, no large-scale analyses of Musa genomic sequence have been conducted. This study compares genomic sequence in two Musa species with orthologous regions in the rice genome. We produced 1.4 Mb of Musa sequence from 13 BAC clones, annotated and analyzed them along with 4 previously sequenced BACs. The 443 predicted genes revealed that Zingiberales genes share GC content and distribution characteristics with eudicot and Poaceae genomes. Comparison with rice revealed microsynteny regions that have persisted since the divergence of the Commelinid orders Poales and Zingiberales at least 117 Mya. The previously hypothesized large-scale duplication event in the common ancestor of major cereal lineages within the Poaceae was verified. The divergence time distributions for Musa-Zingiber (Zingiberaceae, Zingiberales) orthologs and paralogs provide strong evidence for a large-scale duplication event in the Musa lineage after its divergence from the Zingiberaceae approximately 61 Mya. Comparisons of genomic regions from M. acuminata and M. balbisiana revealed highly conserved genome structure, and indicated that these genomes diverged circa 4.6 Mya. These results point to the utility of comparative analyses between distantly-related monocot species such as rice and Musa for improving our understanding of monocot genome evolution. Sequencing the genome of M. acuminata would provide a strong foundation for comparative genomics in the monocots. In addition a genome sequence would aid genomic and genetic analyses of cultivated Musa polyploid genotypes in research aimed at localizing and cloning genes controlling important agronomic traits for breeding purposes.