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1.
Sci Total Environ ; 926: 171793, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38513854

ABSTRACT

Due to global demand, millions of tons of plastics have been widely consumed, resulting in the widespread entry of vast amounts of microplastic particles into the environment. The presence of microplastics (MPs) in water supplies, including bottled water, has undergone systematic review, assessing the potential impacts of MPs on humans through exposure assessment. The main challenges associated with current technologies lie in their ability to effectively treat and completely remove MPs from drinking and supply water. While the risks posed by MPs upon entering the human body have not yet been fully revealed, there is a predicted certainty of negative impacts. This review encompasses a range of current technologies, spanning from basic to advanced treatments and varying in scale. However, given the frequent detection of MPs in drinking and bottled water, it becomes imperative to implement comprehensive management strategies to address this issue effectively. Consequently, integrating current technologies with management options such as life-cycle assessment, circular economy principles, and machine learning is crucial to eliminating this pervasive problem.


Subject(s)
Drinking Water , Water Pollutants, Chemical , Humans , Microplastics , Plastics , Water Pollutants, Chemical/analysis , Environmental Monitoring , Water Supply
2.
Mol Plant ; 15(2): 363-371, 2022 02 07.
Article in English | MEDLINE | ID: mdl-34848348

ABSTRACT

Seed size critically affects grain yield of crops and hence represents a key breeding target. The development of embryo-nourishing endosperm is a key driver of seed expansion. We here report unexpected dual roles of the transcription factor EIN3 in regulating seed size. These EIN3 functions have remained largely undiscovered because they oppose each other. Capitalizing on the analysis of multiple ethylene biosynthesis mutants, we demonstrate that EIN3 represses endosperm and seed development in a pathway regulated by ethylene. We, in addition, provide evidence that EIN3-mediated synergid nucleus disintegration promotes endosperm expansion. Interestingly, synergid nucleus disintegration is not affected in various ethylene biosynthesis mutants, suggesting that this promoting function of EIN3 is independent of ethylene. Whereas the growth-inhibitory ethylene-dependent EIN3 action appears to be encoded by sporophytic tissue, the growth-promoting role of EIN3 is induced by fertilization, revealing a generation conflict that converges toward the key signaling component EIN3.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/metabolism , DNA-Binding Proteins/metabolism , Ethylenes/metabolism , Gene Expression Regulation, Plant/genetics , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Plant Breeding , Seeds/genetics , Seeds/metabolism
3.
Elife ; 92020 02 06.
Article in English | MEDLINE | ID: mdl-32027307

ABSTRACT

Polyploidization, the increase in genome copies, is considered a major driving force for speciation. We have recently provided the first direct in planta evidence for polyspermy induced polyploidization. Capitalizing on a novel sco1-based polyspermy assay, we here show that polyspermy can selectively polyploidize the egg cell, while rendering the genome size of the ploidy-sensitive central cell unaffected. This unprecedented result indicates that polyspermy can bypass the triploid block, which is an established postzygotic polyploidization barrier. In fact, we here show that most polyspermy-derived seeds are insensitive to the triploid block suppressor admetos. The robustness of polyspermy-derived plants is evidenced by the first transcript profiling of triparental plants and our observation that these idiosyncratic organisms segregate tetraploid offspring within a single generation. Polyspermy-derived triparental plants are thus comparable to triploids recovered from interploidy crosses. Our results expand current polyploidization concepts and have important implications for plant breeding.


Ever since Darwin published his most famous book on the theory of evolution, scientists have sought to identify the mechanisms that drive the formation of new species. This is especially true for plant biologists who have long been fascinated by the extraordinary diversity of flowering plants.Many species of flowering plant first evolved after a dramatic increase in the DNA content of an individual plant, a process termed polyploidization. Most explanations for polyploidization involve a pollen grain making sperm that mistakenly contain two sets of chromosomes rather than one. Yet, it is difficult to reconcile this explanation with an important aspect of plant reproduction ­ the so-called "triploid block".Fertilization in flowering plants is more complicated than in animals. While one sperm fertilizes the egg cell to make the plant embryo, a second sperm from the same pollen grain must fertilize another cell to form the endosperm, the tissue that will nourish the embryo as it develops. This means that sperm with twice the normal number of chromosomes would affect the DNA content of both the embryo and the endosperm. Yet, an endosperm that receives extra paternal DNA typically halts the development of the seed via a process known as the triploid block, meaning it was not clear how often this process would actually result in a polyploid plant.In 2017, researchers reported that plants can, on rare occasions, generate polyploid offspring via a different route: the fertilization of one egg with two sperm rather than one. Now, Mao et al. ­ who include several researchers involved in the 2017 study ­ show that this process, termed "polyspermy", can introduce extra copies of DNA into just the egg cell, meaning it can bypass the triploid block of the endosperm.The experiments involved a model plant called Arabidopsis, and a screen of over 55,000 seeds identified about a dozen with embryos that had three parents, one mother and two fathers. Notably, most of these three-parent embryos developed in seeds that contained endosperm with the regular number of chromosomes and hence escaped the triploid block.These new results show that polyspermy provides plants with a means to essentially sneak extra copies of DNA 'behind the back' of the DNA-sensitive endosperm and into the next generation. They also give new insight in how polyploidization may have shaped the evolution of flowering plants and have important implications for agriculture where the breeding of new "hybrid" crops has often been limited by incompatibilities in the endosperm.


Subject(s)
Fertilization , Plant Breeding , Triploidy , Animals , Plant Physiological Phenomena , RNA, Messenger/genetics , Seeds
4.
BMC Pregnancy Childbirth ; 18(1): 416, 2018 Oct 24.
Article in English | MEDLINE | ID: mdl-30355329

ABSTRACT

BACKGROUND: Influenza and pertussis vaccines have been recommended in Australia for women during each pregnancy since 2010 and 2015, respectively. Estimating vaccination coverage and identifying factors affecting uptake are important for improving antenatal immunisation services. METHODS: A random sample of 800 Western Australian women ≥18 years of age who gave birth between 4th April and 4th October 2015 were selected. Of the 454 (57%) who were contactable by telephone, 424 (93%) completed a survey. Data were weighted by maternal age and area of residence to ensure representativeness. The proportion immunised against influenza and pertussis was the main outcome measure; multivariate logistic regression was used to identify factors significantly associated with antenatal vaccination. Results from the 2015 study were compared to similar surveys conducted in 2012-2014. RESULTS: In 2015, 71% (95% CI 66-75) of women received pertussis-containing vaccine and 61% (95% CI 56-66) received influenza vaccine during pregnancy; antenatal influenza vaccine coverage was 18% higher than in 2014 (43%; 95% CI: 34-46). Pertussis and influenza vaccine were co-administered for 68% of the women who received both vaccines. The majority of influenza vaccinations in 2015 were administered during the third trimester of pregnancy, instead of the second trimester, as was observed in prior years. Women whose care provider recommended both antenatal vaccinations had significantly higher odds of being vaccinated against both influenza and pertussis (OR 33.3, 95% CI: 15.15-73.38). Of unvaccinated mothers, 53.6% (95% CI: 45.9-61.3) and 78.3% (95% CI: 70.4-85.3) reported that they would have been vaccinated against influenza and pertussis, respectively, if their antenatal care provider had recommended it. CONCLUSIONS: Pertussis vaccination coverage was high in the first year of an antenatal immunisation program in Western Australia. Despite a substantial increase in influenza vaccination uptake between 2014 and 2015, coverage remained below that for pertussis. Our data suggest influenza and pertussis vaccination rates of 83% and 94%, respectively, are achievable if providers were to recommend them to all pregnant women.


Subject(s)
Influenza Vaccines/administration & dosage , Pertussis Vaccine/administration & dosage , Prenatal Care/statistics & numerical data , Vaccination Coverage/statistics & numerical data , Vaccination/statistics & numerical data , Adolescent , Adult , Attitude to Health , Cross-Sectional Studies , Female , Health Surveys , Humans , Influenza, Human/prevention & control , Pregnancy , Pregnant Women , Western Australia , Whooping Cough/prevention & control , Young Adult
5.
Nat Commun ; 9(1): 1493, 2018 04 11.
Article in English | MEDLINE | ID: mdl-29643363

ABSTRACT

This Article contained errors in Fig. 3 that were brought to our attention by the authors during the production process but, inadvertently, were not corrected before publication. The tick marks on the y-axis in panels b, f, and k, and the median line in the box-and-whisker plot for biparental diploid plants (BP) in panel i were shifted downwards by up to 2 mm. This has now been corrected in both the PDF and HTML versions of the Article.

6.
Nat Commun ; 8(1): 1033, 2017 10 18.
Article in English | MEDLINE | ID: mdl-29044107

ABSTRACT

It is considered an inviolable principle that sexually reproducing organisms have no more than two parents and fertilization of an egg by multiple sperm (polyspermy) is lethal in many eukaryotes. In flowering plants polyspermy has remained a hypothetical concept, due to the lack of tools to unambiguously identify and trace this event. We established a high-throughput polyspermy detection assay, which uncovered that supernumerary sperm fusion does occur in planta and can generate viable polyploid offspring. Moreover, polyspermy can give rise to seedlings with one mother and two fathers, challenging the bi-organismal concept of parentage. The polyspermy derived triploids are taller and produce bigger organs than plants resulting from a regular monospermic fertilization. In addition, we demonstrate the hybridization potential of polyspermy by instantly combining three different Arabidopsis accessions in one zygote. Our results provide direct evidence for polyspermy as a route towards polyploidy, which is considered a major plant speciation mechanism.


Subject(s)
Arabidopsis/genetics , Germ Cells, Plant/growth & development , Polyploidy , Arabidopsis/growth & development , Arabidopsis/physiology , Germ Cells, Plant/physiology , Reproduction , Seeds/genetics , Seeds/growth & development , Zygote/growth & development
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