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1.
Cureus ; 16(4): e58979, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38800330

ABSTRACT

Infective endocarditis (IE) remains a formidable challenge in clinical practice due to several causative agents, each presenting with unique diagnostic and therapeutic dilemmas. Kocuria kristinae, a coagulase-negative, catalase-positive Gram-positive coccus, has recently emerged as an uncommon but increasingly recognized pathogen in the cause of IE. This case report highlights the clinical characteristics, risk factors, and challenges associated with Kocuria kristinae-induced IE. We conducted a comprehensive literature review and identified several case reports on Kocuria kristinae as a causative agent. Due to its indolent nature and the subtle presentation of symptoms, along with its ability to form biofilms, delayed diagnosis of Kocuria is often seen, thereby emphasizing the need for heightened clinical suspicion. The predisposing factors for Kocuria kristinae infection include underlying cardiac abnormalities, prosthetic heart valves, and immunocompromised states. Additionally, antimicrobial susceptibility patterns and optimal treatment strategies remain unclear, warranting further investigation. This abstract presents the case of a 75-year-old male with IE secondary to Kocuria kristinae on a prosthetic mitral valve. We aim to highlight the need for increased awareness among clinicians to facilitate early recognition and prompt initiation of targeted therapeutic interventions. Unraveling the intricacies of Kocuria kristinae's pathogenicity is crucial for refining diagnostic approaches and optimizing patient outcomes.

2.
Cureus ; 16(1): e53159, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38420066

ABSTRACT

Myelodysplastic syndrome (MDS) is characterized by failure to initiate hematopoiesis or impaired maturation of cells, often presenting with pancytopenias with or without associated fatigue, infections, or inappropriate bleeding and bruising. Karyotype analyses of MDS patients commonly show deletion of the q arm of chromosome 7, suggesting loss of this region is likely implicated in the insufficient hematopoiesis seen in MDS. The predisposition to deletion of 7q is commonly inherited, with clinical presentation in early childhood associated with pancytopenia or hematological malignancy. In this case, we present a 66-year-old female who was incidentally found to be pancytopenic in the emergency department while being evaluated for dyspnea, with a bone marrow biopsy later confirming a diagnosis of MDS with monosomy 7. Sporadic loss of 7q can occur at any stage in life without any family history of hematological disease. Our patient has no known personal or family history of MDS, with normal blood counts during hospitalization three years prior, suggesting de novo loss of 7q occurring at greater than 60 years of age.

3.
Nat Commun ; 14(1): 8357, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38102128

ABSTRACT

Teleost fishes, which are the largest and most diverse group of living vertebrates, have a rich history of ancient and recent polyploidy. Previous studies of allotetraploid common carp and goldfish (cyprinids) reported a dominant subgenome, which is more expressed and exhibits biased gene retention. However, the underlying mechanisms contributing to observed 'subgenome dominance' remains poorly understood. Here we report high-quality genomes of twenty-one cyprinids to investigate the origin and subsequent subgenome evolution patterns following three independent allopolyploidy events. We identify the closest extant relatives of the diploid progenitor species, investigate genetic and epigenetic differences among subgenomes, and conclude that observed subgenome dominance patterns are likely due to a combination of maternal dominance and transposable element densities in each polyploid. These findings provide an important foundation to understanding subgenome dominance patterns observed in teleost fishes, and ultimately the role of polyploidy in contributing to evolutionary innovations.


Subject(s)
Carps , Evolution, Molecular , Animals , Polyploidy , Genome/genetics , Epigenesis, Genetic , Genome, Plant
4.
Plant Cell ; 34(9): 3233-3260, 2022 08 25.
Article in English | MEDLINE | ID: mdl-35666179

ABSTRACT

Long intergenic noncoding RNAs (lincRNAs) are a large yet enigmatic class of eukaryotic transcripts that can have critical biological functions. The wealth of RNA-sequencing (RNA-seq) data available for plants provides the opportunity to implement a harmonized identification and annotation effort for lincRNAs that enables cross-species functional and genomic comparisons as well as prioritization of functional candidates. In this study, we processed >24 Tera base pairs of RNA-seq data from >16,000 experiments to identify ∼130,000 lincRNAs in four Brassicaceae: Arabidopsis thaliana, Camelina sativa, Brassica rapa, and Eutrema salsugineum. We used nanopore RNA-seq, transcriptome-wide structural information, peptide data, and epigenomic data to characterize these lincRNAs and identify conserved motifs. We then used comparative genomic and transcriptomic approaches to highlight lincRNAs in our data set with sequence or transcriptional conservation. Finally, we used guilt-by-association analyses to assign putative functions to lincRNAs within our data set. We tested this approach on a subset of lincRNAs associated with germination and seed development, observing germination defects for Arabidopsis lines harboring T-DNA insertions at these loci. LincRNAs with Brassicaceae-conserved putative miRNA binding motifs, small open reading frames, or abiotic-stress modulated expression are a few of the annotations that will guide functional analyses into this cryptic portion of the transcriptome.


Subject(s)
Arabidopsis , Brassicaceae , RNA, Long Noncoding , Genomics , Sequence Analysis, RNA , Transcriptome
5.
Am J Bot ; 109(7): 1177-1190, 2022 07.
Article in English | MEDLINE | ID: mdl-35716121

ABSTRACT

PREMISE: Camelina (gold-of-pleasure or false flax) is an ancient oilseed crop with emerging applications in the production of sustainable, low-input biofuels. Previous domestication hypotheses suggested a European or western Asian origin, yet little genetic evidence has existed to assess the geographical origin for this crop, and archaeological data have not been systematically surveyed. METHODS: We utilized genotyping-by-sequencing of 185 accessions of C. sativa and its wild relatives to examine population structure within the crop species and its relationship to populations of its wild progenitor, C. microcarpa; cytotype variation was also assessed in both species. In a complementary analysis, we surveyed the archaeological literature to identify sites with archaeobotanical camelina remains and assess the timing and prevalence of usage across Europe and western Asia. RESULTS: The majority of C. microcarpa sampled in Europe and the United States belongs to a variant cytotype (2n = 38) with a distinct evolutionary origin from that of the crop lineage (2n = 40). Populations of C. microcarpa from Transcaucasia (South Caucasus) are most closely related to C. sativa based on cytotype and population structure; in combination with archaeological insights, these data refute prior hypotheses of a European domestication origin. CONCLUSIONS: Our findings support a Caucasus, potentially Armenian, origin of C. sativa domestication. We cannot definitively determine whether C. sativa was intentionally targeted for domestication in its own right or instead arose secondarily through selection for agricultural traits in weedy C. sativa, as originally proposed by Vavilov for this species.


Subject(s)
Brassicaceae , Domestication , Brassicaceae/genetics , Geography , Phenotype , Plant Weeds
6.
Hortic Res ; 92022 Jan 05.
Article in English | MEDLINE | ID: mdl-35031794

ABSTRACT

The genus Camelina (Brassicaceae) comprises 7-8 diploid, tetraploid, and hexaploid species. Of particular agricultural interest is the biofuel crop, C. sativa (gold-of-pleasure or false flax), an allohexaploid domesticated from the widespread weed, C. microcarpa. Recent cytogenetics and genomics work has uncovered the identity of the parental diploid species involved in ancient polyploidization events in Camelina. However, little is known about the maternal subgenome ancestry of contemporary polyploid species. To determine the diploid maternal contributors of polyploid Camelina lineages, we sequenced and assembled 84 Camelina chloroplast genomes for phylogenetic analysis. Divergence time estimation was used to infer the timing of polyploidization events. Chromosome counts were also determined for 82 individuals to assess ploidy and cytotypic variation. Chloroplast genomes showed minimal divergence across the genus, with no observed gene-loss or structural variation. Phylogenetic analyses revealed C. hispida as a maternal diploid parent to the allotetraploid Camelina rumelica, and C. neglecta as the closest extant diploid contributor to the allohexaploids C. microcarpa and C. sativa. The tetraploid C. rumelica appears to have evolved through multiple independent hybridization events. Divergence times for polyploid lineages closely related to C. sativa were all inferred to be very recent, at only ~65 thousand years ago. Chromosome counts confirm that there are two distinct cytotypes within C. microcarpa (2n = 38 and 2n = 40). Based on these findings and other recent research, we propose a model of Camelina subgenome relationships representing our current understanding of the hybridization and polyploidization history of this recently-diverged genus.

7.
BMC Plant Biol ; 20(1): 423, 2020 Sep 14.
Article in English | MEDLINE | ID: mdl-32928104

ABSTRACT

BACKGROUND: Camelina sativa (gold-of-pleasure) is a traditional European oilseed crop and emerging biofuel source with high levels of desirable fatty acids. A twentieth century germplasm bottleneck depleted genetic diversity in the crop, leading to recent interest in using wild relatives for crop improvement. However, little is known about seed oil content and genetic diversity in wild Camelina species. RESULTS: We used gas chromatography, environmental niche assessment, and genotyping-by-sequencing to assess seed fatty acid composition, environmental distributions, and population structure in C. sativa and four congeners, with a primary focus on the crop's wild progenitor, C. microcarpa. Fatty acid composition differed significantly between Camelina species, which occur in largely non-overlapping environments. The crop progenitor comprises three genetic subpopulations with discrete fatty acid compositions. Environment, subpopulation, and population-by-environment interactions were all important predictors for seed oil in these wild populations. A complementary growth chamber experiment using C. sativa confirmed that growing conditions can dramatically affect both oil quantity and fatty acid composition in Camelina. CONCLUSIONS: Genetics, environmental conditions, and genotype-by-environment interactions all contribute to fatty acid variation in Camelina species. These insights suggest careful breeding may overcome the unfavorable FA compositions in oilseed crops that are predicted with warming climates.


Subject(s)
Brassicaceae/genetics , Brassicaceae/metabolism , Plant Oils/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Seeds/genetics , Seeds/metabolism , Adaptation, Physiological , Biofuels , Crops, Agricultural/genetics , Crops, Agricultural/metabolism , Europe , Gene Expression Regulation, Plant , Gene-Environment Interaction , Genotype , Plants, Genetically Modified/metabolism , Seeds/chemistry
8.
Plant Cell ; 31(11): 2596-2612, 2019 11.
Article in English | MEDLINE | ID: mdl-31451448

ABSTRACT

Complexes of diploid and polyploid species have formed frequently during the evolution of land plants. In false flax (Camelina sativa), an important hexaploid oilseed crop closely related to Arabidopsis (Arabidopsis thaliana), the putative parental species as well as the origin of other Camelina species remained unknown. By using bacterial artificial chromosome-based chromosome painting, genomic in situ hybridization, and multi-gene phylogenetics, we aimed to elucidate the origin and evolution of the polyploid complex. Genomes of diploid camelinas (Camelina hispida, n = 7; Camelina laxa, n = 6; and Camelina neglecta, n = 6) originated from an ancestral n = 7 genome. The allotetraploid genome of Camelina rumelica (n = 13, N6H) arose from hybridization between diploids related to C. neglecta (n = 6, N6) and C. hispida (n = 7, H), and the N subgenome has undergone a substantial post-polyploid fractionation. The allohexaploid genomes of C. sativa and Camelina microcarpa (n = 20, N6N7H) originated through hybridization between an auto-allotetraploid C. neglecta-like genome (n = 13, N6N7) and C. hispida (n = 7, H), and the three subgenomes have remained stable overall since the genome merger. Remarkably, the ancestral and diploid Camelina genomes were shaped by complex chromosomal rearrangements, resembling those associated with human disorders and resulting in the origin of genome-specific shattered chromosomes.plantcell;31/11/2596/FX1F1fx1.


Subject(s)
Brassicaceae/genetics , Chromothripsis , Diploidy , Evolution, Molecular , Genome, Plant , Arabidopsis/genetics , Brassicaceae/classification , Chromosomes, Plant , Hybridization, Genetic , Phylogeny , Polyploidy
9.
Front Plant Sci ; 10: 184, 2019.
Article in English | MEDLINE | ID: mdl-30842785

ABSTRACT

There is a need to explore renewable alternatives (e.g., biofuels) that can produce energy sources to help reduce the reliance on fossil oils. In addition, the consumption of fossil oils adversely affects the environment and human health via the generation of waste water, greenhouse gases, and waste solids. Camelina sativa, originated from southeastern Europe and southwestern Asia, is being re-embraced as an industrial oilseed crop due to its high seed oil content (36-47%) and high unsaturated fatty acid composition (>90%), which are suitable for jet fuel, biodiesel, high-value lubricants and animal feed. C. sativa's agronomic advantages include short time to maturation, low water and nutrient requirements, adaptability to adverse environmental conditions and resistance to common pests and pathogens. These characteristics make it an ideal crop for sustainable agricultural systems and regions of marginal land. However, the lack of genetic and genomic resources has slowed the enhancement of this emerging oilseed crop and exploration of its full agronomic and breeding potential. Here, a core of 213 spring C. sativa accessions was collected and genotyped. The genotypic data was used to characterize genetic diversity and population structure to infer how natural selection and plant breeding may have affected the formation and differentiation within the C. sativa natural populations, and how the genetic diversity of this species can be used in future breeding efforts. A total of 6,192 high-quality single nucleotide polymorphisms (SNPs) were identified using genotyping-by-sequencing (GBS) technology. The average polymorphism information content (PIC) value of 0.29 indicate moderate genetic diversity for the C. sativa spring panel evaluated in this report. Population structure and principal coordinates analyses (PCoA) based on SNPs revealed two distinct subpopulations. Sub-population 1 (POP1) contains accessions that mainly originated from Germany while the majority of POP2 accessions (>75%) were collected from Eastern Europe. Analysis of molecular variance (AMOVA) identified 4% variance among and 96% variance within subpopulations, indicating a high gene exchange (or low genetic differentiation) between the two subpopulations. These findings provide important information for future allele/gene identification using genome-wide association studies (GWAS) and marker-assisted selection (MAS) to enhance genetic gain in C. sativa breeding programs.

10.
PhytoKeys ; (115): 51-57, 2019.
Article in English | MEDLINE | ID: mdl-30692865

ABSTRACT

Camelinaneglecta is described as a new diploid species and its relationship to the other diploids of the genus and to the somewhat superficially similar tetraploid C.rumelica and hexaploid C.microcarpa, are discussed. SEM of seed and stem trichomes of the new species are presented.

11.
Mol Phylogenet Evol ; 127: 834-842, 2018 10.
Article in English | MEDLINE | ID: mdl-29933039

ABSTRACT

Camelina sativa (false flax or gold-of-pleasure) is an Old World oilseed crop that fell out of use in the mid 20th Century but has recently gained renewed interest as a biofuel source. The crop is hexaploid, and its relationship to its diploid and polyploid congeners has remained unresolved. Using 54 accessions representing five species sampled across Camelina's center of diversity in Turkey and the Caucasus, we performed phylogenetic and genetic diversity analyses using RADseq genotyping and ITS sequencing. Flow cytometry was performed to assess relationships between genome size and phylogenetic groupings. Accessions fell into distinct, highly-supported clades that accord with named species, indicating that morphological characters can reliably distinguish members of the genus. A phylogenetically distinct lineage from Turkey may represent a currently unrecognized diploid species. In most analyses, C. sativa accessions nest within those of C. microcarpa, suggesting that the crop is descended from this wild hexaploid species. This inference is further supported by their similar genome size, and by lower genetic diversity in C. sativa, which is consistent with a domestication bottleneck. These analyses provide the first definitive phylogeny of C. sativa and its wild relatives, and they point to C. microcarpa as the crop's wild ancestor.


Subject(s)
Brassicaceae/classification , Phylogeny , Base Sequence , Brassicaceae/genetics , DNA, Intergenic/genetics , Genetic Variation , Genome, Plant , Geography , Likelihood Functions , Polyploidy
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