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Dispersal and establishment traits provide a colonization advantage for a polyploid apomictic plant.American Journal of Botany Apr 2023Apomictic plants (reproducing asexually through seed) often have larger ranges and occur at higher latitudes than closely related sexuals, a pattern known as...
PREMISE
Apomictic plants (reproducing asexually through seed) often have larger ranges and occur at higher latitudes than closely related sexuals, a pattern known as geographical parthenogenesis (GP). Explanations for GP include differences in colonizing ability due to reproductive assurance and direct/indirect effects of polyploidy (most apomicts are polyploid) on ecological tolerances. While life history traits associated with dispersal and establishment also contribute to the potential for range expansion, few studies compare these traits in related apomicts and sexuals.
METHODS
We investigated differences in early life history traits between diploid-sexual and polyploid-apomictic Townsendia hookeri (Asteraceae), which displays a classic pattern of GP. Using lab and greenhouse experiments, we measured seed dispersal traits, germination success, and seedling size and survival in sexual and apomictic populations from across the range of the species.
RESULTS
While theory predicts that trade-offs between dispersal and establishment traits should be common, this was largely not the case in T. hookeri. Apomictic seeds had both lower terminal velocity (staying aloft longer when dropped) and higher germination success than sexual seeds. While there were no differences in seedling size between reproductive types, apomicts did, however, have slightly lower seedling survival than sexuals.
CONCLUSIONS
These differences in early life history traits, combined with reproductive assurance conferred by apomixis, suggest that apomicts achieve a greater range through advantages in their ability to both spread and establish.
Topics: Apomixis; Polyploidy; Parthenogenesis; Plants; Seeds
PubMed: 36857315
DOI: 10.1002/ajb2.16149 -
Plants (Basel, Switzerland) Feb 2023The term "Geographical parthenogenesis" describes the phenomenon that asexual organisms usually occupy larger and more northern distribution areas than their sexual... (Review)
Review
The term "Geographical parthenogenesis" describes the phenomenon that asexual organisms usually occupy larger and more northern distribution areas than their sexual relatives, and tend to colonize previously glaciated areas. Several case studies on alpine and arctic plants confirm the geographical pattern, but the causal factors behind the phenomenon are still unclear. Research of the last decade in several plant families has shed light on the question and evaluated some of the classical evolutionary theories. Results confirmed, in general, that the advantages of uniparental reproduction enable apomictic plants to re-colonize faster in larger and more northern distribution areas. Associated factors like polyploidy seem to contribute mainly to the spatial separation of sexual and asexual cytotypes. Ecological studies suggest a better tolerance of apomicts to colder climates and temperate extremes, whereby epigenetic flexibility and phenotypic plasticity play an important role in occupying ecological niches under harsh conditions. Genotypic diversity appears to be of lesser importance for the distributional success of asexual plants. Classical evolutionary theories like a reduced pressure of biotic interactions in colder climates and hence an advantage to asexuals (Red Queen hypothesis) did not gain support from studies on plants. However, it is also still enigmatic why sexual outcrossing remains the predominant mode of reproduction also in alpine floras. Constraints for the origin of apomixis might play a role. Interestingly, some studies suggest an association of sexuality with abiotic stresses. Light stress in high elevations might explain why most alpine plants retain sexual reproduction despite other environmental factors that would favor apomixis. Directions for future research will be given.
PubMed: 36840192
DOI: 10.3390/plants12040844 -
Insects Jan 2023Artificial parthenogenetic induction via thermal stimuli in silkworm is an important technique that has been used in sericultural production. However, the molecular...
Artificial parthenogenetic induction via thermal stimuli in silkworm is an important technique that has been used in sericultural production. However, the molecular mechanism underlying it remains largely unknown. We have created a fully parthenogenetic line (PL) with more than 85% occurrence and 80% hatching rate via hot water treatment and genetic selection, while the parent amphigenetic line (AL) has less than 30% pigmentation rate and less than 1% hatching rate when undergoing the same treatment. Here, isobaric tags for relative and absolute quantitation (iTRAQ)-based analysis were used to investigate the key proteins and pathways associated with silkworm parthenogenesis. We uncovered the unique proteomic features of unfertilized eggs in PL. In total, 274 increased abundance proteins and 211 decreased abundance proteins were identified relative to AL before thermal induction. Function analysis displayed an increased level of translation and metabolism in PL. After thermal induction, 97 increased abundance proteins and 187 decreased abundance proteins were identified. An increase in stress response-related proteins and decrease in energy metabolism suggested that PL has a more effective response to buffer the thermal stress than AL. Cell cycle-related proteins, including histones, and spindle-related proteins were decreased in PL, indicating an important role of this decrease in the process of ameiotic parthenogenesis.
PubMed: 36835703
DOI: 10.3390/insects14020134 -
Insects Jan 2023is a parthenogenetic weevil native to South America that is currently distributed worldwide. This flightless species is polyphagous and capable of modifying gene...
Genetically Depauperate and Still Successful: Few Multilocus Genotypes of the Introduced Parthenogenetic Weevil (Coleoptera: Curculionidae) Prevail in the Continental United States.
is a parthenogenetic weevil native to South America that is currently distributed worldwide. This flightless species is polyphagous and capable of modifying gene expression regimes for responding to stressful situations. was first reported in the continental United States in 1879 and has rapidly colonized most of the world since. Previous studies suggested that an invader genotype successfully established even in areas of unsuitable environmental conditions. In the present work, we analyze mitochondrial and nuclear sequences from 71 individuals collected in 13 localities across three states in the southern US, in order to describe the genetic diversity in this area of introduction that has not yet been previously studied. Our results suggest that 97% of the samples carry the most prevalent invader genotype already reported, while the rest shows a close mitochondrial derivative. This would support the hypothesis of a general purpose genotype, with parthenogenesis and its associated lack of recombination maintaining the linkage of genetic variants capable of coping with adverse conditions and enlarging its geographical range. However, demographic advantages related to parthenogenetic reproduction as the main driver of geographic expansion (such as the foundation of a population with a single virgin female) cannot be ruled out. Given the historical introduction records and the prevalence of the invader genotype, it is possible that the continental US may act as a secondary source of introductions to other areas. We propose that both the parthenogenesis and scarce genetic variation in places of introduction may, in fact, be an asset that allows to thrive across a range of environmental conditions.
PubMed: 36835682
DOI: 10.3390/insects14020113 -
International Journal of Molecular... Feb 2023In our recent work, we observed that triple-negative breast cancer MDA-MB-231 cells respond to doxorubicin (DOX) via "mitotic slippage" (MS), discarding cytosolic...
In our recent work, we observed that triple-negative breast cancer MDA-MB-231 cells respond to doxorubicin (DOX) via "mitotic slippage" (MS), discarding cytosolic damaged DNA during the process that provides their resistance to this genotoxic treatment. We also noted two populations of polyploid giant cells: those budding surviving offspring, versus those reaching huge ploidy by repeated MS and persisting for several weeks. Their separate roles in the recovery from treatment remained unclear. The current study was devoted to characterising the origin and relationship of these two sub-populations in the context of MS. MS was hallmarked by the emergence of nuclear YAP1/OCT4A/MOS/EMI2-positivity featuring a soma-germ transition to the meiotic-metaphase-arrested "maternal germ cell". In silico, the link between modules identified in the inflammatory innate immune response to cytosolic DNA and the reproductive module of female pregnancy (upregulating placenta developmental genes) was observed in polyploid giant cells. Asymmetry of the two subnuclei types, one repairing DNA and releasing buds enriched by CDC42/ACTIN/TUBULIN and the other persisting and degrading DNA in a polyploid giant cell, was revealed. We propose that when arrested in MS, a "maternal cancer germ cell" may be parthenogenetically stimulated by the placental proto-oncogene parathyroid-hormone-like-hormone, increasing calcium, thus creating a "female pregnancy-like" system within a single polyploid giant cancer cell.
Topics: Female; Pregnancy; Humans; Placenta; Neoplasms; Giant Cells; Polyploidy; DNA; Hormones
PubMed: 36834647
DOI: 10.3390/ijms24043237 -
GigaByte (Hong Kong, China) 2022Parasitoid wasps in the genus are commonly used as biological pest control agents of whiteflies and armored scale insects in greenhouses or the field. They are also...
Parasitoid wasps in the genus are commonly used as biological pest control agents of whiteflies and armored scale insects in greenhouses or the field. They are also hosts of the bacterial endosymbiont , which can cause reproductive manipulation phenotypes, including parthenogenesis, feminization, and cytoplasmic incompatibility (the last is mainly studied in ). Despite their biological and economic importance, there are no published genomes and only one public transcriptome. Here, we applied a mapping-and-removal approach to eliminate known contaminants from previously-obtained Illumina sequencing data. We generated transcriptome assemblies for both female and male which contain 45,986 and 54,762 final coding sequences, respectively. Benchmarking Single-Copy Orthologs results indicate both assemblies are highly complete. Preliminary analyses revealed the presence of homologs of sex-determination genes characterized in other insects and putative venom proteins. Our male and female transcriptomes will be valuable tools to better understand the biology of and their evolutionary relatives, particularly in studies involving insects of only one sex.
PubMed: 36824530
DOI: 10.46471/gigabyte.68 -
Revista Da Sociedade Brasileira de... 2023Scorpions are a leading cause of envenomation in Brazil. The species Tityus serrulatus is associated with the most severe cases, especially in children. Despite not...
BACKGROUND
Scorpions are a leading cause of envenomation in Brazil. The species Tityus serrulatus is associated with the most severe cases, especially in children. Despite not being endemic to the state of Santa Catarina, such occurrences have increased more than 500% in the state recently. Therefore, this study aimed to analyze the occurrence of envenomation by T. serrulatus, attended by the Center for Toxicological Information and Assistance of Santa Catarina.
METHODS
This was a retrospective and descriptive study of the occurrence of T. serrulatus, identified by the agency, from 2014 to 2021 in Santa Catarina, using data obtained by the BI-DATATOX system.
RESULTS
A total of 112 occurrences were classified as envenomation. Of these cases, 48.2% were recorded in the Itajaí Valley region and 33% in Greater Florianópolis. Men were involved in 59.8% of these, and the most common age group was 20-39 years (39.3%). Most envenomation occurred in urban areas (89.3%) under non-occupational circumstances (83%). Stings were more frequent on the hands (50.9%). Care was sought within 1 h after the event in 75.9% of the cases, and 94.6% were classified as mild.
CONCLUSIONS
Occurrence of envenomation involving T. serrulatus in Santa Catarina increased significantly during the study period. Most cases occurred in urbanized areas, which suggests that they might have been transported from other states, and it must be considered that, in the urban environment, scorpions find a large supply of food and shelter and a reduced number of specific predators, allied to parthenogenesis.
Topics: Male; Child; Animals; Humans; Young Adult; Adult; Scorpions; Brazil; Retrospective Studies; Scorpion Stings; Environment; Scorpion Venoms
PubMed: 36820659
DOI: 10.1590/0037-8682-0434-2022 -
Frontiers in Genome Editing 2023The phylum Nematoda harbors a huge diversity of species in a broad range of ecosystems and habitats. Nematodes share a largely conserved Bauplan but major differences...
The phylum Nematoda harbors a huge diversity of species in a broad range of ecosystems and habitats. Nematodes share a largely conserved Bauplan but major differences have been found in early developmental processes. The development of the nematode model organism has been studied in great detail for decades. These efforts have provided the community with a large number of protocols and methods. Unfortunately, many of these tools are not easily applicable in non- nematodes. In recent years it has become clear that many crucial genes in the developmental toolkit are absent in other nematode species. It is thus necessary to study the developmental program of other nematode species in detail to understand evolutionary conservation and novelty in the phylum. sp. PS1159 is a non-parasitic nematode exhibiting parthenogenetic reproduction and we are establishing the species to comparatively study evolution, biodiversity, and alternative reproduction and survival strategies. Here, we demonstrate the first successful application of the CRISPR/Cas9 system for genome editing in sp. PS1159 and the closely related hermaphroditic species sp. JU765 applying the non-homologous end joining and the homology-directed repair (HDR) mechanisms. Using microinjections and modifying published protocols from and we induced mutations in the orthologue of This resulted in a visible uncoordinated twitching phenotype. We also compared the HDR efficiency following the delivery of different single-stranded oligodeoxynucleotides (ssODNs). Our work will expand the applicability for a wide range of non-model nematodes from across the tree and facilitate functional analysis into the evolution of parthenogenesis, changes in the developmental program of Nematoda, and cryptobiosis.
PubMed: 36818277
DOI: 10.3389/fgeed.2023.1078359 -
Journal of Experimental Botany Apr 2023Apomixis is considered a potentially revolutionary tool to generate high-quality food at a lower cost and shorter developmental time due to clonal seed production... (Review)
Review
Apomixis is considered a potentially revolutionary tool to generate high-quality food at a lower cost and shorter developmental time due to clonal seed production through apomeiosis and parthenogenesis. In the diplosporous type of apomixis, meiotic recombination and reduction are circumvented either by avoiding or failing meiosis or by a mitotic-like division. Here, we review the literature on diplospory, from early cytological studies dating back to the late 19th century to recent genetic findings. We discuss diplosporous developmental mechanisms, including their inheritance. Furthermore, we compare the strategies adopted to isolate the genes controlling diplospory with those to produce mutants forming unreduced gametes. Nowadays, the dramatically improved technologies of long-read sequencing and targeted CRISPR/Cas mutagenesis justify the expectation that natural diplospory genes will soon be identified. Their identification will answer questions such as how the apomictic phenotype can be superimposed upon the sexual pathway and how diplospory genes have evolved. This knowledge will contribute to the application of apomixis in agriculture.
Topics: Apomixis; Seeds; Reproduction, Asexual; Inheritance Patterns; Phenotype; Reproduction
PubMed: 36794770
DOI: 10.1093/jxb/erad054 -
ZooKeys 2022The genus Foddai, Bonato, Pereira & Minelli, 2003 is a monotypic genus established on the basis of the possibly introduced species Foddai, Bonato, Pereira & Minelli,...
The genus Foddai, Bonato, Pereira & Minelli, 2003 is a monotypic genus established on the basis of the possibly introduced species Foddai, Bonato, Pereira & Minelli, 2003, from New York, USA. In the present study, in a field survey conducted throughout Japan, -like specimens were collected from Honshu, Shikoku, and Kyushu. These specimens clearly showed the diagnostic characteristics of the genus but were morphologically distinct from . Furthermore, morphological analysis and DNA barcoding revealed that these specimens could be assigned to two distinct undescribed species. On the basis of these results, Tsukamoto, and Tsukamoto, are described. The three species can be distinguished from each other on the basis of the following combination of characteristics: presence or absence of a pair of smooth or weakly areolate areas along the posterior part of the paraclypeal sutures; the width-to-length ratio of the denticle on the trochanteroprefemur; the pigmentation of the denticle on the tarsungulum. Moreover, the field survey resulted in the collection of exclusively female specimens of Tsukamoto, , which shows the possibility of parthenogenesis of this species.
PubMed: 36761074
DOI: 10.3897/zookeys.1115.83946