Mitchell-Olds T

References (4)

Title : The Reference Genome of the Halophytic Plant Eutrema salsugineum - Yang_2013_Front.Plant.Sci_4_46
Author(s) : Yang R , Jarvis DE , Chen H , Beilstein MA , Grimwood J , Jenkins J , Shu S , Prochnik S , Xin M , Ma C , Schmutz J , Wing RA , Mitchell-Olds T , Schumaker KS , Wang X
Ref : Front Plant Sci , 4 :46 , 2013
Abstract : Halophytes are plants that can naturally tolerate high concentrations of salt in the soil, and their tolerance to salt stress may occur through various evolutionary and molecular mechanisms. Eutrema salsugineum is a halophytic species in the Brassicaceae that can naturally tolerate multiple types of abiotic stresses that typically limit crop productivity, including extreme salinity and cold. It has been widely used as a laboratorial model for stress biology research in plants. Here, we present the reference genome sequence (241 Mb) of E. salsugineum at 8x coverage sequenced using the traditional Sanger sequencing-based approach with comparison to its close relative Arabidopsis thaliana. The E. salsugineum genome contains 26,531 protein-coding genes and 51.4% of its genome is composed of repetitive sequences that mostly reside in pericentromeric regions. Comparative analyses of the genome structures, protein-coding genes, microRNAs, stress-related pathways, and estimated translation efficiency of proteins between E. salsugineum and A. thaliana suggest that halophyte adaptation to environmental stresses may occur via a global network adjustment of multiple regulatory mechanisms. The E. salsugineum genome provides a resource to identify naturally occurring genetic alterations contributing to the adaptation of halophytic plants to salinity and that might be bioengineered in related crop species.
ESTHER : Yang_2013_Front.Plant.Sci_4_46
PubMedSearch : Yang_2013_Front.Plant.Sci_4_46
PubMedID: 23518688
Gene_locus related to this paper: theha-e4mxu0 , thesl-v4nk72 , eutsa-v4l4z1 , eutsa-v4kk46 , eutsa-v4mej3 , eutsa-v4ns11 , eutsa-v4mg02 , eutsa-v4mqm9 , eutsa-v4k1y6 , eutsa-v4lad0 , eutsa-v4nr92 , eutsa-v4kqc3 , eutsa-v4l0s2 , eutsa-v4lip3 , eutsa-v4kkg2 , eutsa-v4kvd3 , eutsa-v4m9g4 , eutsa-v4lqg2 , eutsa-v4lp36 , eutsa-v4km66 , eutsa-v4nhr8 , eutsa-v4kqx9 , eutsa-v4lv73

Title : Signatures of demography and recombination at coding genes in naturally-distributed populations of Arabidopsis lyrata subsp. petraea - Vigueira_2013_PLoS.One_8_e58916
Author(s) : Vigueira CC , Rauh B , Mitchell-Olds T , Lawton-Rauh AL
Ref : PLoS ONE , 8 :e58916 , 2013
Abstract : Demography impacts the observed standing level of genetic diversity present in populations. Distinguishing the relative impacts of demography from selection requires a baseline of expressed gene variation in naturally occurring populations. Six nuclear genes were sequenced to estimate the patterns and levels of genetic diversity in natural Arabidopsis lyrata subsp. petraea populations that differ in demographic histories since the Pleistocene. As expected, northern European populations have genetic signatures of a strong population bottleneck likely due to glaciation during the Pleistocene. Levels of diversity in the northern populations are about half of that in central European populations. Bayesian estimates of historical population size changes indicate that central European populations also have signatures of population size change since the last glacial maxima, suggesting that these populations are not as stable as previously thought. Time since divergence amongst northern European populations is higher than amongst central European populations, suggesting that the northern European populations were established before the Pleistocene and survived glaciation in small separated refugia. Estimates of demography based on expressed genes are complementary to estimates based on microsatellites and transposable elements, elucidating temporal shifts in population dynamics and confirming the importance of marker selection for tests of demography.
ESTHER : Vigueira_2013_PLoS.One_8_e58916
PubMedSearch : Vigueira_2013_PLoS.One_8_e58916
PubMedID: 23554957
Gene_locus related to this paper: arath-clh1

Title : The shrunken genome of Arabidopsis thaliana. - Oyama_2008_Plant.Syst.Evol_273_257
Author(s) : Oyama RK , Clauss MJ , Formanova N , Kroymann J , Schmid KJ , Vogel H , Weniger K , Windsor AJ , Mitchell-Olds T
Ref : Plant Syst Evol , 273 :257 , 2008
Abstract : This paper examines macro and micro-level patterns of genome size evolution in the Brassicaceae. A phylogeny of 25 relatives of Arabidopsis thaliana was reconstructed using four molecular markers under both parsimony and Bayesian methods. Reconstruction of genome size (C value) evolution as a discrete character and as a continuous character was also performed. In addition, size dynamics in small chromosomal regions were assessed by comparing genomic clones generated for Arabidopsis lyrata and for Boechera stricta to the fully sequenced genome of A. thaliana. The results reveal a sevenfold variation in genome size among the taxa investigated and that the small genome size of A. thaliana is derived. Our results also indicate that the genome is free to increase or decrease in size across these evolutionary lineages without a directional bias. These changes are accomplished by insertions and deletions at both large and small-scales occurring mostly in intergenic regions, with repetitive sequences and transposable elements implicated in genome size increases. The focus upon taxa relatively closely related to the model organism A. thaliana, and the combination of complementary approaches, allows for unique insights into the processes driving genome size
ESTHER : Oyama_2008_Plant.Syst.Evol_273_257
PubMedSearch : Oyama_2008_Plant.Syst.Evol_273_257
Gene_locus related to this paper: arath-q66gm8 , arath-SCP26

Title : Independent ancient polyploidy events in the sister families Brassicaceae and Cleomaceae - Schranz_2006_Plant.Cell_18_1152
Author(s) : Schranz ME , Mitchell-Olds T
Ref : Plant Cell , 18 :1152 , 2006
Abstract : Recent studies have elucidated the ancient polyploid history of the Arabidopsis thaliana (Brassicaceae) genome. The studies concur that there was at least one polyploidy event occurring some 14.5 to 86 million years ago (Mya), possibly near the divergence of the Brassicaceae from its sister family, Cleomaceae. Using a comparative genomics approach, we asked whether this polyploidy event was unique to members of the Brassicaceae, shared with the Cleomaceae, or an independent polyploidy event in each lineage. We isolated and sequenced three genomic regions from diploid Cleome spinosa (Cleomaceae) that are each homoeologous to a duplicated region shared between At3 and At5, centered on the paralogs of SEPALLATA (SEP) and CONSTANS (CO). Phylogenetic reconstructions and analysis of synonymous substitution rates support the hypothesis that a genomic triplication in Cleome occurred independently of and more recently than the duplication event in the Brassicaceae. There is a strong correlation in the copy number (single versus duplicate) of individual genes, suggesting functionally consistent influences operating on gene copy number in these two independently evolving lineages. However, the amount of gene loss in Cleome is greater than in Arabidopsis. The genome of C. spinosa is only 1.9 times the size of A. thaliana, enabling comparative genome analysis of separate but related polyploidy events.
ESTHER : Schranz_2006_Plant.Cell_18_1152
PubMedSearch : Schranz_2006_Plant.Cell_18_1152
PubMedID: 16617098
Gene_locus related to this paper: 9rosi-q1kus0 , 9rosi-q1kux4