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1.
Cell Rep Methods ; 4(9): 100860, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39255794

RESUMEN

Cardiomyocyte proliferation is a challenging metric to assess. Current methodologies have limitations in detecting the generation of new cardiomyocytes and technical challenges that reduce widespread applicability. Here, we describe an improved cell suspension and imaging-based methodology that can be broadly employed to assess cardiomyocyte cell division in standard laboratories across a multitude of model organisms and experimental conditions. We highlight additional metrics that can be gathered from the same cell preparations to enable additional relevant analyses to be performed. We incorporate additional antibody stains to address potential technical concerns of miscounting. Finally, we employ this methodology with a dual-thymidine analog-labeling approach to a post-infarction murine model, which allowed us to robustly identify unique cycling events, such as cardiomyocytes undergoing multiple rounds of cell division.


Asunto(s)
División Celular , Proliferación Celular , Infarto del Miocardio , Miocitos Cardíacos , Infarto del Miocardio/patología , Miocitos Cardíacos/patología , Animales , Ratones , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Masculino
2.
Life (Basel) ; 14(9)2024 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-39337984

RESUMEN

Previous studies on the mountain plant Ranunculus kuepferi concluded that apomictic self-compatible tetraploids have experienced a niche shift toward a colder climate during the Holocene, which suggests a fitness advantage over the sexual, self-sterile diploid parents under cold and stressful high-mountain conditions. However, there is still a lack of information on whether reproductive development would be advantageous for tetraploids. Here, we report on microsporogenesis, megagametogenesis, the dynamics of flower and seed development, and the consequences for reproductive success in a common garden experiment along a 1000 m climatic elevation gradient and in natural populations. Flower buds were initiated in the year preceding anthesis and passed winter in a pre-meiotic stage. Flower morphology differed in the known cytotype-specific way in that tetraploid flowers produced about twice as many carpels and fewer petals, stamens, and pollen grains than diploid flowers. Tetraploids developed precociously aposporous embryo sacs and showed a high rate of developmental disturbances. Sexual seed formation prevailed in diploids and pseudogamous apomixis in tetraploids. Along the elevation gradient, stigma pollen load, pollen performance, and seed output decreased. Combinations of reproductive traits, namely, bypass of meiosis irregularities and uniparental reproduction, might have promoted the vast expansion of apomictic R. kuepferi lines across the European Alps.

3.
Plant Divers ; 46(4): 476-490, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39280974

RESUMEN

Polyploidy is a major factor in the evolution of plants, yet we know little about the origin and evolution of polyploidy in intertidal species. This study aimed to identify the evolutionary transitions in three true-mangrove species of the genus Acanthus distributed in the Indo-West Pacific region. For this purpose, we took an integrative approach that combined data on morphology, cytology, climatic niche, phylogeny, and biogeography of 493 samples from 42 geographic sites. Our results show that the Acanthus ilicifolius lineage distributed east of the Thai-Malay Peninsula possesses a tetraploid karyotype, which is morphologically distinct from that of the lineage on the west side. The haplotype networks and phylogenetic trees for the chloroplast genome and eight nuclear genes reveal that the tetraploid species has two sub-genomes, one each from A. ilicifolius and A . ebracteatus, the paternal and maternal parents, respectively. Population structure analysis also supports the hybrid speciation history of the new tetraploid species. The two sub-genomes of the tetraploid species diverged from their diploid progenitors during the Pleistocene. Environmental niche models revealed that the tetraploid species not only occupied the near-entire niche space of the diploids, but also expanded into novel environments. Our findings suggest that A. ilicifolius species distributed on the east side of the Thai-Malay Peninsula should be regarded as a new species, A. tetraploideus, which originated from hybridization between A. ilicifolius and A. ebracteatus, followed by chromosome doubling. This is the first report of a true-mangrove allopolyploid species that can reproduce sexually and clonally reproduction, which explains the long-term adaptive potential of the species.

4.
Pest Manag Sci ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39229824

RESUMEN

BACKGROUND: The endocycle can generate cells referred to as 'polyploid'. Fizzy-related protein (Fzr) plays an important role in driving the mitosis-to-endocycle transition. The brown planthopper (BPH), Nilaparvata lugens (Stål), a serious insect pest, feeds exclusively on rice. However, polyploidy and its regulatory mechanisms are poorly understood in BPH. RESULTS: Here, we found that the ploidy levels of follicles H (FH) and accessory gland (AG) significantly increased with BPH age when examining the polyploidy of FH and AG of salivary glands. Fzr was identified as an important regulator for polyploidy in BPH salivary gland. Knockdown of Fzr resulted in a decrease in cell size and DNA content in nymph salivary glands. Fzr knockdown transcriptionally upregulated cyclin-dependent kinase 1 (CDK1), CDK2, cyclin A (CycA) and CycB, and downregulated CycD, CycE, Myc and mini-chromosome maintenance protein 2-7 (MCM2-7). Phenotypically, Fzr knockdown significantly suppressed salivary protein production, feeding and survival in BPH nymphs. CONCLUSION: Our results show that BPH salivary glands exhibit obvious polyploidy, and Fzr positively regulates the endocycle in nymph salivary gland. These findings provide clues for the study of the regulatory mechanisms of insect polyploidy. © 2024 Society of Chemical Industry.

5.
Plant J ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276372

RESUMEN

Cultivar Williams 82 has served as the reference genome for the soybean research community since 2008, but is known to have areas of genomic heterogeneity among different sub-lines. This work provides an updated assembly (version Wm82.a6) derived from a specific sub-line known as Wm82-ISU-01 (seeds available under USDA accession PI 704477). The genome was assembled using Pacific BioSciences HiFi reads and integrated into chromosomes using HiC. The 20 soybean chromosomes assembled into a genome of 1.01Gb, consisting of 36 contigs. The genome annotation identified 48 387 gene models, named in accordance with previous assembly versions Wm82.a2 and Wm82.a4. Comparisons of Wm82.a6 with other near-gapless assemblies of Williams 82 reveal large regions of genomic heterogeneity, including regions of differential introgression from the cultivar Kingwa within approximately 30 Mb and 25 Mb segments on chromosomes 03 and 07, respectively. Additionally, our analysis revealed a previously unknown large (>20 Mb) heterogeneous region in the pericentromeric region of chromosome 12, where Wm82.a6 matches the 'Williams' haplotype while the other two near-gapless assemblies do not match the haplotype of either parent of Williams 82. In addition to the Wm82.a6 assembly, we also assembled the genome of 'Fiskeby III,' a rich resource for abiotic stress resistance genes. A genome comparison of Wm82.a6 with Fiskeby III revealed the nucleotide and structural polymorphisms between the two genomes within a QTL region for iron deficiency chlorosis resistance. The Wm82.a6 and Fiskeby III genomes described here will enhance comparative and functional genomics capacities and applications in the soybean community.

6.
Heliyon ; 10(16): e36375, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39253144

RESUMEN

Wheat, a highly versatile staple crop cultivated extensively for its grains on a global scale, is poised to experience increased demand to sustain the burgeoning population, owing to its superior nutritional potential. Modern wheat, a hexaploid species, has evolved through the introgression of numerous preceding ploidies, including Einkorn, Emmer, Aegilops, and others, each possessing distinct qualitative and quantitative traits. Scientometric and topical analyses serve as effective tools to quantitatively evaluate scientific research by measuring the knowledge expressed in scientific publications and keywords. Thus, comprehending the research status regarding wheat domestication events within primary, secondary, and tertiary gene pools is paramount for enhancing wheat production. In this study, we analyze data retrieved from PubMed to elucidate the research status and identify bottlenecks across different ploidy of genomic pools of wheat. The publication trends on wheat have experienced exponential growth over the past three decades, with China emerging as a leading center for publications. In contrast to the publication frequency observed in hexaploid common wheat, scholarly output concerning Einkorn and Aegilops is approximately tenfold lesser, with emmer trailing behind at three times fewer publications. This discrepancy underscores the prioritization of expedited research initiatives targeting these species, aimed at elucidating latent biological characteristics and optimizing their breeding capabilities. Keywords such as "stress," "GWAS," and "gene" are prominent, reflecting the challenges posed by climatic factors on wheat production and their mitigation through molecular breeding and gene manipulation. Notably, the keyword "einkorn" highlights its potential as a donor for fine-tuning traits related to wheat adaptation processes and quality, crucial for modern wheat's survivability under adverse climates. Conversely, higher publication rates on emmer are primarily associated with Italy, possibly due to its favorable Mediterranean climate for tetraploid wheat. Keywords like "Pasta" and "Ochratoxin, DON" are prevalent, with the former being derived from durum wheat and the latter being reported in higher amounts in durum compared to other wheat species, rendering it less suitable for consumption. Enriched keywords such as "genome" and "resistance" underscore the critical characteristics of Aegilops. Other significant keywords like "Aceria tosichella" possibly indicate multiple stages of resistance conferred by Aegilops, while the presence of the grain softness protein "puroindoline" enhances its acceptability for donation by Aegilops. Spelt, a close relative of common wheat, exhibits a research trend with thousands of annual publications and enriched keywords such as "stress" and "yield" reflect the current scientific emphasis on wheat research. Furthermore, hierarchical keywords like "bio-control" and "celiac disease" merit consideration for future research on hexaploid wheat.

7.
Cancers (Basel) ; 16(17)2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39272964

RESUMEN

Cell division is crucial for the survival of living organisms. Human cells undergo three types of cell division: mitosis, meiosis, and amitosis. The former two types occur in somatic cells and germ cells, respectively. Amitosis involves nuclear budding and occurs in cells that exhibit abnormal nuclear morphology (e.g., polyploidy) with increased cell size. In the early 2000s, Kirsten Walen and Rengaswami Rajaraman and his associates independently reported that polyploid human cells are capable of producing progeny via amitotic cell division, and that a subset of emerging daughter cells proliferate rapidly, exhibit stem cell-like properties, and can contribute to tumorigenesis. Polyploid cells that arise in solid tumors/tumor-derived cell lines are referred to as polyploid giant cancer cells (PGCCs) and are known to contribute to therapy resistance and disease recurrence following anticancer treatment. This commentary provides an update on some of these intriguing discoveries as a tribute to Drs. Walen and Rajaraman.

8.
Plant Physiol ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39325737

RESUMEN

Indian jujube (Ziziphus mauritiana) holds a prominent position in the global fruit and pharmaceutical markets. Here, we report the assemblies of haplotype-resolved, telomere-to-telomere genomes of autotetraploid wild and cultivated Indian jujube plants using a two-stage assembly strategy. The generation of these genomes permitted in-depth investigations into the divergence and evolutionary history of this important fruit crop. Using a graph-based pan-genome constructed from eight monoploid genomes, we identified structural variation (SV)-FST hotspots and SV hotspots. Gap-free genomes provide a means to obtain a global view of centromere structures. We identified presence-absence variation-related genes in four monoploid genomes (cI, cIII, wI, and wIII) and resequencing populations. We also present the population structure and domestication trajectory of the Indian jujube based on the resequencing of 73 wild and cultivated accessions. Metabolomic and transcriptomic analyses of mature fruits of wild and cultivated accessions unveiled the genetic basis underlying loss of fruit astringency during domestication of Indian jujube. This study reveals mechanisms underlying the divergence, evolution, and domestication of the autotetraploid Indian jujube and provides rich and reliable genetic resources for future research.

9.
New Phytol ; 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39329429
10.
Mol Phylogenet Evol ; 200: 108184, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39209045

RESUMEN

Poales, as one of the largest orders of angiosperm, holds crucial economic and ecological importance. Nevertheless, achieving a consensus topology has been challenging in previous studies due to limited molecular data and sparse taxon sampling. The uneven distribution of species diversity among families and the factors leading to elevated species richness in certain lineages have also been subjects of ongoing discussion and investigation. In this study, we conducted a comprehensive sampling, including representatives from all 14 families and 85 taxa of Poales, along with five additional outgroups. To reconstruct the phylogeny of Poales, we employed a combination of coalescent and concatenation methods on three nuclear gene sets (1093, 491, 143) and one plastid gene set (53), which were inferenced from genomic data. We also conducted phylogenetic hypothesis analyses to evaluate two major conflicting nodes detected in phylogenetic analyses. As a result, we successfully resolved the backbone of Poales and provided a timeline for its evolutionary history. We recovered the sister relationship between Typhaceae and Bromeliaceae as the earliest diverging families within Poales. The clade consisting of Ecdeiocoleaceae and Joinvilleaceae was recovered as the sister group of Poaceae. Within the xyrid clade, Mayacaceae and Erioaculaceae + Xyridaceae successively diverged along the backbone of Poales. The topology of [Aristidoideae, ((Micrairoideae, Panicoideae), (Arundinoideae, (Chloridoideae, Danthonioideae)))] within the PACMAD clade has received strong support from multiple findings. We also delved into the underlying biological factors that contributed to the conflicting nodes observed in the phylogenetic analysis. Apart from the uncertainty regarding the sister group of Poaceae caused by cytonuclear discordance, frequent hybridization and polyploidy may have contributed to other conflicting nodes. We identified 26 putative whole-genome duplication (WGD) events within Poales. However, apart from the σ-WGD and the ρ-WGD, we did not observe any potential polyploid events that could be directly linked to the species diversification in specific lineages. Furthermore, there was a significant increase in the net diversification rate of Poales following the K-Pg boundary.


Asunto(s)
Hibridación Genética , Filogenia , Poliploidía , Análisis de Secuencia de ADN , Genómica , Genoma de Planta
11.
Plant Sci ; 348: 112236, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39186951

RESUMEN

Polyploidy is thought to be an evolutionary and systematic mechanism for gene flow and phenotypic advancement in flowering plants. It is a natural phenomenon that promotes diversity by creating new permutations enhancing the prime potentials as compared to progenitors. Two different pathways have been recognized in studying polyploidy in nature; mitotic or somatic chromosome doubling and cytogenetics variation. Secondly, the vital influence of being polyploid is its heritable property (unreduced reproductive cells) formed during first and second-division restitution (FDR & SDR). Different approaches either chemical (Colchicine, Oryzalin, Caffeine, Trifuralin, or phosphoric amides) or gaseous i.e. Nitrous oxide have been deliberated as strong polyploidy causing agents. A wide range of cytogenetic practices like chromosomes study, ploidy, genome analysis, and plant morphology and anatomy have been studied in different plant species. Flow cytometry for ploidy and chromosome analysis through fluorescence and genomic in situ hybridization (FISH & GISH) are the basic methods to evaluate heredity substances sampled from leaves and roots. Many horticultural crops have been developed successfully and released commercially for consumption. Moreover, some deep detailed studies are needed to check the strong relationship between unique morphological features and genetic makeup concerning genes and hormonal expression in a strong approach.


Asunto(s)
Productos Agrícolas , Genoma de Planta , Poliploidía , Productos Agrícolas/genética , Evolución Biológica , Cromosomas de las Plantas/genética , Genómica/métodos
12.
Appl Plant Sci ; 12(4): e11580, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184196

RESUMEN

Phylogenetic inference of polyploid species is the first step towards understanding their patterns of diversification. In this paper, we review the challenges and limitations of inferring species relationships of polyploid plants using traditional phylogenetic sequencing approaches, as well as the mischaracterization of the species tree from single or multiple gene trees. We provide a roadmap to infer interspecific relationships among polyploid lineages by comparing and evaluating the application of current phylogenetic, phylogenomic, transcriptomic, and whole-genome approaches using different sequencing platforms. For polyploid species tree reconstruction, we assess the following criteria: (1) the amount of prior information or tools required to capture the genetic region(s) of interest; (2) the probability of recovering homeologs for polyploid species; and (3) the time efficiency of downstream data analysis. Moreover, we discuss bioinformatic pipelines that can reconstruct networks of polyploid species relationships. In summary, although current phylogenomic approaches have improved our understanding of reticulate species relationships in polyploid-rich genera, the difficulties of recovering reliable orthologous genes and sorting all homeologous copies for allopolyploids remain a challenge. In the future, assembled long-read sequencing data will assist the recovery and identification of multiple gene copies, which can be particularly useful for reconstructing the multiple independent origins of polyploids.

13.
Appl Plant Sci ; 12(4): e11607, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184203

RESUMEN

Advancements in genome assembly and sequencing technology have made whole genome sequence (WGS) data and reference genomes accessible to study polyploid species. Compared to popular reduced-representation sequencing approaches, the genome-wide coverage and greater marker density provided by WGS data can greatly improve our understanding of polyploid species and polyploid biology. However, biological features that make polyploid species interesting also pose challenges in read mapping, variant identification, and genotype estimation. Accounting for characteristics in variant calling like allelic dosage uncertainty, homology between subgenomes, and variance in chromosome inheritance mode can reduce errors. Here, I discuss the challenges of variant calling in polyploid WGS data and discuss where potential solutions can be integrated into a standard variant calling pipeline.

14.
Appl Plant Sci ; 12(4): e11605, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184197

RESUMEN

Premise: Most traits are polygenic and most genes are pleiotropic, resulting in complex, integrated phenotypes. Polyploidy presents an excellent opportunity to explore the evolution of phenotypic integration as entire genomes are duplicated, allowing for new associations among traits and potentially leading to enhanced or reduced phenotypic integration. Despite the multivariate nature of phenotypic evolution, studies often rely on simplistic bivariate correlations that cannot accurately represent complex phenotypes or data reduction techniques that can obscure specific trait relationships. Methods: We apply network modeling, a common gene co-expression analysis, to the study of phenotypic integration to identify multivariate patterns of phenotypic evolution, including anatomy and morphology (structural) and physiology (functional) traits in response to whole genome duplication in the genus Brassica. Results: We identify four key structural traits that are overrepresented in the evolution of phenotypic integration. Seeding networks with key traits allowed us to identify structure-function relationships not apparent from bivariate analyses. In general, allopolyploids exhibited larger, more robust networks indicative of increased phenotypic integration compared to diploids. Discussion: Phenotypic network analysis may provide important insights into the effects of selection on non-target traits, even when they lack direct correlations with the target traits. Network analysis may allow for more nuanced predictions of both natural and artificial selection.

15.
Appl Plant Sci ; 12(4): e11606, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184199

RESUMEN

Premise: Traditional methods of ploidal-level estimation are tedious; using DNA sequence data for cytotype estimation is an ideal alternative. Multiple statistical approaches to leverage sequence data for ploidy inference based on site-based heterozygosity have been developed. However, these approaches may require high-coverage sequence data, use inappropriate probability distributions, or have additional statistical shortcomings that limit inference abilities. We introduce nQuack, an open-source R package that addresses the main shortcomings of current methods. Methods and Results: nQuack performs model selection for improved ploidy predictions. Here, we implement expectation maximization algorithms with normal, beta, and beta-binomial distributions. Using extensive computer simulations that account for variability in sequencing depth, as well as real data sets, we demonstrate the utility and limitations of nQuack. Conclusions: Inferring ploidy based on site-based heterozygosity alone is difficult. Even though nQuack is more accurate than similar methods, we suggest caution when relying on any site-based heterozygosity method to infer ploidy.

16.
Front Plant Sci ; 15: 1439985, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184574

RESUMEN

Speciation and diversification patterns in angiosperms are frequently shaped by niche evolution. Centaurium Hill is a Mediterranean genus with ca. 25 species, of which 60% are polyploids (tetra- and hexaploids), distributed mainly in the Mediterranean Basin and in areas with temperate and arid climates of Asia, Europe, North-Central Africa and North America. The evolutionary history of this genus has been studied using morphological, biogeographical and molecular approaches, but its climatic niche characterization and its relation with genome evolution (chromosome number and ploidy level) has not been addressed yet. Thus, this study aims to identify the role of the evolution of climatic niche, ploidy level, life cycle and floral traits in the diversification of Centaurium. Climatic niche characterization involved estimating present climate preferences using quantitative data and reconstructing ancestral niches to evaluate climatic niche shifts. The evolution of climatic niche towards selective optima determined by ploidy level (three ploidy levels) and different binary traits (polyploidy, floral size, floral display, herkogamy and life cycle) was addressed under the Ornstein-Uhlenbeck model. Chromosome number evolution was inferred using the ChromoSSE model, testing if changes are clado- or anagenetic. Chromosome number evolution and its link with cladogenesis, life cycle and floral traits was modeled on the phylogeny. The reconstruction of the ancestral niches shows that Centaurium originated in a mild climate and diversified to both humid and cold as well as to dry and warmer climates. Niche conservatism was estimated in the climatic niche of the ancestors, while the climatic niche of the current taxa experienced transitions from their ancestors' niche. Besides, the evolution of climatic niche towards multiple selective optima determined by the studied traits was supported, life cycle optima receiving the highest support. The reconstruction of chromosome number transitions shows that the rate of speciation process resulting from chromosomal changes (chromosomal cladogenesis) is similar to that of non-chromosomal cladogenesis. Additionally, dependent evolution of floral size, floral display and herkogamy with chromosome number variation was supported. In conclusion, polyploidization is a crucial process in the Mediterranean region that assisted speciation and diversification into new areas with different climates, entailing niche shifts and evolution of reproductive strategies.

17.
Evol Lett ; 8(4): 550-560, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39100231

RESUMEN

The shift from outcrossing to self-fertilization is one of the main evolutionary transitions in plants and has broad effects on evolutionary trajectories. In Brassicaceae, the ability to inhibit self-fertilization is controlled by 2 genes, SCR and SRK, tightly linked within the S-locus. A series of small non-coding RNAs also encoded within the S-locus regulates the transcriptional activity of SCR alleles, resulting in a linear dominance hierarchy between them. In Brassicaceae, natural allopolyploid species are often self-compatible (SC) even when one of the progenitor species is self-incompatible, but the reason why polyploid lineages tend to lose self-incompatibility (SI) and the timing of the loss of SI (immediately after ancestral hybridization between the progenitor species, or at a later stage after the formation of allopolyploid lineages) have generally remained elusive. We used a series of synthetic diploid and tetraploid hybrids obtained between self-fertilizing Capsella orientalis and outcrossing Capsella grandiflora to test whether the breakdown of SI could be observed immediately after hybridization, and whether the occurrence of SC phenotypes could be explained by the dominance interactions between S-haplotypes inherited from the parental lineages. We used RNA-sequencing data from young inflorescences to measure allele-specific expression of the SCR gene and infer dominance interactions in the synthetic hybrids. We then evaluated the seed set from autonomous self-pollination in the synthetic hybrids. Our results demonstrate that self-compatibility of the hybrids depends on the relative dominance between S-alleles inherited from the parental species, confirming that SI can be lost instantaneously upon formation of the ancestral allopolyploid lineage. They also confirm that the epigenetic regulation that controls dominance interactions between S-alleles can function between subgenomes in allopolyploids. Together, our results illustrate how a detailed knowledge of the mechanisms controlling SI can illuminate our understanding of the patterns of co-variation between the mating system and changes in ploidy.

18.
Front Aging ; 5: 1429156, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39136004

RESUMEN

The article gives a brief description of geroprotection and rejuvenation methods known to date, presenting their main mechanisms and limitations. To overcome the main limitations of the process of rejuvenation, it is possible to use a process called "cell autocloning." The principle of the proposed method of rejuvenation is as follows: a periodic process of autocloning of the cell nucleus is initiated in the cellular genome with the formation of one unstable daughter copy and its subsequent self-elimination. In this case, the process of cell division stops in the phase of nuclei divergence without subsequent physical separation of the cell itself. This is especially important for postmitotic cells, where the looping of the "unidirectional" line of the ontogenesis program into a "ring" will mean their transition into renewable cells. The prototype for autocloning mechanisms could be the already known ways in which cells adapt to the increasing amount of their damage over time. These are polyploidy and asymmetric cell division, relying on which it is possible to obtain a renewable process of cell nuclei division, when only the original nucleus remains as a result of division. Although this is not a simple task, there are possible pathways to its solution using approaches that can suggest modern knowledge from the field of molecular and cell biology and genetics. The realization of such a goal will require a lot of work, but the expected result justifies it.

19.
Am J Bot ; : e16391, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39126164

RESUMEN

PREMISE: Intraspecific variation in drought resistance traits, such as drought escape, appear to be frequent within wild, ruderal forb species. Understanding how these traits are arrayed across the landscape, particularly in association with climate, is critical to developing forbs for wildland restoration programs. Use of forbs is requisite for maintaining biological diversity and ecological services. METHODS: Using 6074 greenhouse-grown Chaenactis douglasii seedlings from 95 wild, seed-sourced populations across the western United States, we recorded bolting phenology and estimated genome size using flow cytometry. Mixed-effects regression models were used to assess whether climate of seed origin was predictive for bolting phenology and genome size. RESULTS: Variation in bolting, reflecting an annual vs. perennial lifespan in this species, was observed in 8.7% of the plants, with bolting plants disproportionately occurring in locations with warm, arid climates. Populations with increasing heat and aridity were positively correlated with observed bolting (r = 0.61, p < 0.0001). About one-third (22%) of the total (61%) lifespan variation was attributed to seed source climate and annual heat moisture index, a measure of aridity. Genome size had no significant effect on bolting. Projected climate modeling for mid-century (2041-2070) supports an increasing occurrence of annual lifespan. CONCLUSIONS: Our analyses support a drought escape, bet-hedging strategy in C. douglasii. Populations exposed to greater aridity exhibited a higher proportion of individuals with an annual lifespan. Drought escape leading to an annual lifespan can affect how seeds are propagated and deployed for climate-informed restoration.

20.
Am J Bot ; 111(8): e16395, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39164922

RESUMEN

All flowering plants are now recognized as diploidized paleopolyploids (Jiao et al., 2011; One Thousand Plant Transcriptomes Initiative, 2019), and polyploid species comprise approximately 30% of contemporary plant species (Wood et al., 2009; Barker et al., 2016a). A major implication of these discoveries is that, to appreciate the evolution of plant diversity, we need to understand the fundamental biology of polyploids and diploidization. This need is broadly recognized by our community as there is a continued, growing interest in polyploidy as a research topic. Over the past 25 years, the sequencing and analysis of plant genomes has revolutionized our understanding of the importance of polyploid speciation to the evolution of land plants.


Asunto(s)
Genoma de Planta , Genómica , Poliploidía , Evolución Biológica , Magnoliopsida/genética
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