Abstract:
PREMISE OF THE STUDY:Despite being highly fertile and occupying a large geographic region, the North American heartleaf bittercress (Cardamine cordifolia; Brassicaceae) has a puzzling triploid-like chromosome number (2n = 3x = 24). As most triploids are sterile, we embarked on a detailed analysis of the C. cordifolia genome to elucidate its origin and structure. METHODS:Mitotic and meiotic chromosome complement of C. cordifolia was analyzed by comparative chromosome painting using chromosome-specific BAC contigs of Arabidopsis thaliana. Resulting chromosome patterns were documented by multicolor fluorescence microscopy and compared with known ancestral and extant Brassicaceae genomes. KEY RESULTS:We discovered that C. cordifolia is not a triploid hybrid but a diploidized tetraploid with the prevalence of regular, diploid-like meiotic pairing. The ancestral tetraploid chromosome number (2n = 32) was reduced to a triploid-like number (2n = 24) through four terminal chromosome translocations. CONCLUSIONS:The structure of the pseudotriploid C. cordifolia genome results from a stepwise diploidization process after whole-genome duplication. We showed that translocation-based descending dysploidy (from n = 16 to n = 12) was mediated by the formation of five new chromosomes. The genome of C. cordifolia represents the diploidization process in statu nascendi and provides valuable insights into mechanisms of postpolyploidy rediploidization in land plants. Our data further suggest that chromosome number alone does not need to be a reliable proxy of species' evolutionary past and that the same chromosome number may originate either by polyploidization (hybridization) or due to descending dysploidy.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Mandáková T,Gloss AD,Whiteman NK,Lysak MAdoi
10.3732/ajb.1500452subject
Has Abstractpub_date
2016-07-01 00:00:00pages
1187-96issue
7eissn
0002-9122issn
1537-2197pii
ajb.1500452journal_volume
103pub_type
杂志文章abstract:PREMISE OF STUDY:Although there is increasing recognition of the effects of plant intraspecific diversity on consumers, the mechanisms by which such effects cascade-up to higher trophic levels remain elusive. METHODS:We evaluated the effects of plant (lima bean, Phaseolus lunatus) intraspecific diversity on a suite of...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600234
更新日期:2016-10-01 00:00:00
abstract:PREMISE OF THE STUDY:Most pollen walls are interrupted by apertures, thin areas providing access to stigmatic fluids and exit points for pollen tubes. Unexpectedly, pollen tubes of Arabidopsis thaliana are not obligated to pass through apertures and can instead take the shortest route into the stigma, passing directly ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600031
更新日期:2016-06-01 00:00:00
abstract::Expansion of Typha domingensis into areas previously dominated by Cladium jamaicense in the Florida Everglades has been linked to anthropogenic phosphorus (P) enrichment and increased hydroperiod. The principal stress factor for plants in flooded soils is biochemical reduction, the intensity of which is measured as re...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.5.736
更新日期:2003-05-01 00:00:00
abstract:PREMISE:Closely related species occurring in sympatry may experience the negative consequences of interspecific pollen transfer if reproductive isolation (RI) barriers are not in place. We evaluated the importance of pre- and post-pollination RI barriers in three sympatric species of Achimenes (Gesneriaceae), including...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1324
更新日期:2019-07-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:Polymorphic microsatellite primers were developed in the seagrass Halophila ovalis to investigate genetic variation. • METHODS AND RESULTS:Ten polymorphic microsatellite loci were developed in Halophila ovalis. The number of alleles per locus ranged from 2 to 12 across 80 H. ovalis i...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000111
更新日期:2010-06-01 00:00:00
abstract::The FAD2-1 microsomal omega-6 desaturase gene contains a large intron ( approximately 1133 bp [base pairs]) in the 5' untranslated region that may participate in gene regulation and, in GOSSYPIUM:, is evolving at an evolutionary rate useful for elucidating recently diverged lineages. FAD2-1 is single copy in diploid G...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Although our awareness of ploidy diversity has expanded with the application of flow cytometry, we still know little about the extent to which cytotypes within mixed-ploidy populations are genetically differentiated across environmental gradients. METHODS:To address this issue, we reared 14 popula...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500146
更新日期:2016-01-01 00:00:00
abstract:PREMISE OF THE STUDY:The presence or absence of a functional copy of a plastid gene may reflect relaxed selection, and may be phylogenetically significant, reflecting shared ancestry. In some liverworts, the plastid gene cysA is a pseudogene (inferred to be nonfunctional). We surveyed 63 liverworts from all major clade...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100010
更新日期:2011-08-01 00:00:00
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pub_type: 杂志文章
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更新日期:2006-04-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2014-05-01 00:00:00
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journal_title:American journal of botany
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更新日期:1998-08-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:Mountainous regions support high plant productivity, diversity, and endemism, yet are highly vulnerable to climate change. Historical records and model predictions show increasing temperatures across high elevation regions including the Southern Rocky Mountains, which can have a stron...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500156
更新日期:2015-08-01 00:00:00
abstract:PREMISE:The cosmopolitan and ecologically important grass subfamily Aristidoideae comprises the widely distributed genus Aristida (250-290 species), Stipagrostis (50 species, with an African-Asian distribution), and Sartidia (five species, Africa and Madagascar). The subfamily includes species with C(3) (Sartidia and a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100103
更新日期:2011-11-01 00:00:00
abstract::The vegetative cycle of the foliicolous lichen Phyllophiale, from propagule germination to propagule production, was studied by light microscope observation of thalli colonizing plastic cover slips placed within a lowland tropical forest. Discoid propagules germinated by growth of radially arranged fungal cells and de...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.11.1741
更新日期:2002-11-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500336
更新日期:2016-02-01 00:00:00
abstract::Members of tribe Vandeae (Orchidaceae) form a large, pantropical clade of horticulturally important epiphytes. Monopodial leafless members of Vandeae have undergone extreme reduction in habit and represent a novel adaptation to the canopy environment in tropical Africa, Asia, and America. To study the evolution of mon...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.5.770
更新日期:2006-05-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Invasive plant species threaten native plants in multiple ways, one of which is genetic assimilation through hybridization. However, information regarding hybridization between related alien and native plant species is generally lacking. In Hawaii, the invasive Central American species...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300018
更新日期:2013-06-01 00:00:00
abstract:PREMISE:Polyploidy may serve to contribute to range size if autopolyploid cytotypes are adapted to differing ecological conditions. This study aims to establish the geographic distribution of cytotypes within the giant goldenrod (Solidago gigantea), and to assess whether cytotypes exhibit differing ecological tolerance...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1556
更新日期:2020-11-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Verbenaceae consist of trees, shrubs, lianas, and herbs distributed primarily in Latin America, where they occur in a wide array of ecosystems. A second center of diversity exists in Africa. Competing morphology-based classifications that rely on different traits conflict in significan...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000144
更新日期:2010-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200467
更新日期:2013-11-01 00:00:00
abstract::In rainforests, trunk size, strength, crown position, and geometry of a tree affect light interception and the likelihood of mechanical failure. Allometric relationships of tree diameter, wood density, and crown architecture vs. height are described for a diverse range of rainforest trees in Brunei, northern Borneo. T...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.12.1951
更新日期:2007-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-05-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2015-06-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1362
更新日期:2019-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.9.1265
更新日期:2006-09-01 00:00:00
abstract::Isozymatic data taken from 67 Guatemalan collections of maize were subjected to numerical taxonomic analyses to elucidate systematic relationships among the 19 maize races and subraces described for Guatemala by Wellhausen et al. As with Bolivian and Mexican races, isozymatic variation in Guatemalan maize was strongly...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/j.1537-2197.1990.tb13547.x
更新日期:1990-02-01 00:00:00
abstract::Bamboo is considered useful for controlling landslides, but we observed numerous shallow-slope failures in forests of big node bamboo (Phyllostachys nidularia) in Sichuan, China. Therefore, we inventoried landslide occurrence and vegetation type along one valley. To quantify bamboo root anchorage, we performed uprooti...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.7.1129
更新日期:2007-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1700175
更新日期:2017-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.4.549
更新日期:2004-04-01 00:00:00
abstract::Many plant species contain populations with more than one polyploid cytotype, but little is known of the mechanisms maintaining several cytotypes in a population. Andropogon gerardii cytotypes were compared to evaluate different models of autopolyploid cytotype coexistence. The enneaploid (90 chromosome, 9x) cytotype ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-07-01 00:00:00