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1.
New Phytol ; 242(4): 1753-1770, 2024 May.
Article in English | MEDLINE | ID: mdl-38146206

ABSTRACT

Global change is reshaping Earth's biodiversity, but the changing distributions of nonpathogenic fungi remain largely undocumented, as do mechanisms enabling invasions. The ectomycorrhizal Amanita phalloides is native to Europe and invasive in North America. Using population genetics and genomics, we sought to describe the life history traits of this successfully invading symbiotic fungus. To test whether death caps spread underground using hyphae, or aboveground using sexual spores, we mapped and genotyped mushrooms from European and US sites. Larger genetic individuals (genets) would suggest spread mediated by vegetative growth, while many small genets would suggest dispersal mediated by spores. To test whether genets are ephemeral or persistent, we also sampled from populations over time. At nearly every site and across all time points, mushrooms resolve into small genets. Individuals frequently establish from sexual spores. But at one Californian site, a single individual measuring nearly 10 m across dominated. At two Californian sites, the same genetic individuals were discovered in 2004, 2014, and 2015, suggesting single individuals (both large and small) can reproduce repeatedly over relatively long timescales. A flexible life history strategy combining both mycelial growth and spore dispersal appears to underpin the invasion of this deadly perennial ectomycorrhizal fungus.


Subject(s)
Amanita , Forests , Introduced Species , Spores, Fungal , Amanita/genetics , Amanita/growth & development , Amanita/physiology , Time Factors
2.
Nat Commun ; 14(1): 6560, 2023 10 24.
Article in English | MEDLINE | ID: mdl-37875491

ABSTRACT

Canonical sexual reproduction among basidiomycete fungi involves the fusion of two haploid individuals of different mating types, resulting in a heterokaryotic mycelial body made up of genetically different nuclei. Using population genomics data and experiments, we discover mushrooms of the invasive and deadly Amanita phalloides can also be homokaryotic; evidence of sexual reproduction by single, unmated individuals. In California, genotypes of homokaryotic mushrooms are also found in heterokaryotic mushrooms, implying nuclei of homokaryotic mycelia are also involved in outcrossing. We find death cap mating is controlled by a single mating type locus, but the development of homokaryotic mushrooms appears to bypass mating type gene control. Ultimately, sporulation is enabled by nuclei able to reproduce alone as well as with others, and nuclei competent for both unisexuality and bisexuality have persisted in invaded habitats for at least 17 but potentially as long as 30 years. The diverse reproductive strategies of invasive death caps are likely facilitating its rapid spread, suggesting a profound similarity between plant, animal and fungal invasions.


Subject(s)
Agaricales , Basidiomycota , Humans , Animals , Agaricales/genetics , Reproduction/genetics , Basidiomycota/genetics , Genotype , Genes, Mating Type, Fungal
3.
Microorganisms ; 11(7)2023 Jul 18.
Article in English | MEDLINE | ID: mdl-37513002

ABSTRACT

The first genome sequenced of a eukaryotic organism was for Saccharomyces cerevisiae, as reported in 1996, but it was more than 10 years before any of the zygomycete fungi, which are the early-diverging terrestrial fungi currently placed in the phyla Mucoromycota and Zoopagomycota, were sequenced. The genome for Rhizopus delemar was completed in 2008; currently, more than 1000 zygomycete genomes have been sequenced. Genomic data from these early-diverging terrestrial fungi revealed deep phylogenetic separation of the two major clades-primarily plant-associated saprotrophic and mycorrhizal Mucoromycota versus the primarily mycoparasitic or animal-associated parasites and commensals in the Zoopagomycota. Genomic studies provide many valuable insights into how these fungi evolved in response to the challenges of living on land, including adaptations to sensing light and gravity, development of hyphal growth, and co-existence with the first terrestrial plants. Genome sequence data have facilitated studies of genome architecture, including a history of genome duplications and horizontal gene transfer events, distribution and organization of mating type loci, rDNA genes and transposable elements, methylation processes, and genes useful for various industrial applications. Pathogenicity genes and specialized secondary metabolites have also been detected in soil saprobes and pathogenic fungi. Novel endosymbiotic bacteria and viruses have been discovered during several zygomycete genome projects. Overall, genomic information has helped to resolve a plethora of research questions, from the placement of zygomycetes on the evolutionary tree of life and in natural ecosystems, to the applied biotechnological and medical questions.

4.
Ecol Lett ; 26(9): 1523-1534, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37330626

ABSTRACT

Despite host-fungal symbiotic interactions being ubiquitous in all ecosystems, understanding how symbiosis has shaped the ecology and evolution of fungal spores that are involved in dispersal and colonization of their hosts has been ignored in life-history studies. We assembled a spore morphology database covering over 26,000 species of free-living to symbiotic fungi of plants, insects and humans and found more than eight orders of variation in spore size. Evolutionary transitions in symbiotic status correlated with shifts in spore size, but the strength of this effect varied widely among phyla. Symbiotic status explained more variation than climatic variables in the current distribution of spore sizes of plant-associated fungi at a global scale while the dispersal potential of their spores is more restricted compared to free-living fungi. Our work advances life-history theory by highlighting how the interaction between symbiosis and offspring morphology shapes the reproductive and dispersal strategies among living forms.


Subject(s)
Mycorrhizae , Symbiosis , Animals , Humans , Ecosystem , Fungi , Insecta , Plants , Spores, Fungal
5.
bioRxiv ; 2023 Mar 05.
Article in English | MEDLINE | ID: mdl-36778337

ABSTRACT

Canonical sexual reproduction among basidiomycete fungi involves the fusion of two haploid individuals of different sexes, resulting in a heterokaryotic mycelial body made up of genetically different nuclei 1 . Using population genomics data, we discovered mushrooms of the deadly invasive Amanita phalloides are also homokaryotic, evidence of sexual reproduction by single individuals. In California, genotypes of homokaryotic mushrooms are also found in heterokaryotic mushrooms, implying nuclei of homokaryotic mycelia also promote outcrossing. We discovered death cap mating is controlled by a single mating-type locus ( A. phalloides is bipolar), but the development of homokaryotic mushrooms appears to bypass mating-type gene control. Ultimately, sporulation is enabled by nuclei able to reproduce alone as well as with others, and nuclei competent for both unisexuality and bisexuality have persisted in invaded habitats for at least 17 but potentially as long as 30 years. The diverse reproductive strategies of invasive death caps are likely facilitating its rapid spread, revealing a profound similarity between plant, animal and fungal invasions 2,3 .

6.
mSystems ; 7(6): e0105222, 2022 12 20.
Article in English | MEDLINE | ID: mdl-36453934

ABSTRACT

Lipo-chitooligosaccharides (LCOs) are historically known for their role as microbial-derived signaling molecules that shape plant symbiosis with beneficial rhizobia or mycorrhizal fungi. Recent studies showing that LCOs are widespread across the fungal kingdom have raised questions about the ecological function of these compounds in organisms that do not form symbiotic relationships with plants. To elucidate the ecological function of these compounds, we investigate the metabolomic response of the ubiquitous human pathogen Aspergillus fumigatus to LCOs. Our metabolomics data revealed that exogenous application of various types of LCOs to A. fumigatus resulted in significant shifts in the fungal metabolic profile, with marked changes in the production of specialized metabolites known to mediate ecological interactions. Using network analyses, we identify specific types of LCOs with the most significant effect on the abundance of known metabolites. Extracts of several LCO-induced metabolic profiles significantly impact the growth rates of diverse bacterial species. These findings suggest that LCOs may play an important role in the competitive dynamics of non-plant-symbiotic fungi and bacteria. This study identifies specific metabolomic profiles induced by these ubiquitously produced chemicals and creates a foundation for future studies into the potential roles of LCOs as modulators of interkingdom competition. IMPORTANCE The activation of silent biosynthetic gene clusters (BGC) for the identification and characterization of novel fungal secondary metabolites is a perpetual motion in natural product discoveries. Here, we demonstrated that one of the best-studied symbiosis signaling compounds, lipo-chitooligosaccharides (LCOs), play a role in activating some of these BGCs, resulting in the production of known, putative, and unknown metabolites with biological activities. This collection of metabolites induced by LCOs differentially modulate bacterial growth, while the LCO standards do not convey the same effect. These findings create a paradigm shift showing that LCOs have a more prominent role outside of host recognition of symbiotic microbes. Importantly, our work demonstrates that fungi use LCOs to produce a variety of metabolites with biological activity, which can be a potential source of bio-stimulants, pesticides, or pharmaceuticals.


Subject(s)
Chitosan , Mycorrhizae , Humans , Chitin , Chitosan/pharmacology , Oligosaccharides/pharmacology
7.
Front Genet ; 13: 1014044, 2022.
Article in English | MEDLINE | ID: mdl-36212139

ABSTRACT

Fair and equitable benefit sharing of genetic resources is an expectation of the Nagoya Protocol. Although the Nagoya Protocol does not yet formally apply to Digital Sequence Information ("DSI"), discussions are currently underway regarding to include such data through ongoing Convention on Biological Diversity ("CBD") negotiations. While Indigenous Peoples and Local Communities ("IPLC") expect the value generated from genomic data to be subject to benefit sharing arrangements, a range of views are currently being expressed by Nation States, IPLC and other stakeholders. The use of DSI gives rise to unique considerations, creating a gray area as to how it should be considered under the Nagoya Protocol's Access and Benefit Sharing ("ABS") principles. One way for benefit sharing to be enhanced is through the connection of data to proper provenance information. A significant development is the use of digital labeling systems to ensure that the origin of samples is appropriately disclosed. The Traditional Knowledge and Biocultural Labels initiative offers a practical option for data provided to genomic databases. In particular, the BioCultural Labels ("BC Labels") are a mechanism for Indigenous communities to identify and maintain provenance, origin and authority over biocultural material and data generated from Indigenous land and waters held in research, cultural institutions and data repositories. This form of cultural metadata adds value to the research endeavor and the creation of Indigenous fields within databases adds transparency and accountability to the research environment.

8.
Semin Plast Surg ; 36(2): 120-130, 2022 May.
Article in English | MEDLINE | ID: mdl-35937439

ABSTRACT

Today, plastic surgery is a well-known profession with highly respected surgeons from institutions all over the world. Over the last several decades numerous clinical and technological advances have been made, thanks to the dedication and hard work of these outstanding professionals; however, things were not always this way. At the turn of the 20 th century, Israel had yet to be introduced to the field of plastic surgery. However, this all changed with the War of Independence. Humanitarian aid by the prominent South African surgeon, Jack Penn, laid the foundation for the founding fathers of plastic surgery in Israel to establish a strong legacy of producing world-renowned surgeons and innovators. Through this paper, we hope to provide a brief overview of the history of plastic surgery in Israel and what transpired to give us the state of surgical practice we have today.

9.
PLoS One ; 17(5): e0261912, 2022.
Article in English | MEDLINE | ID: mdl-35511895

ABSTRACT

Populations of the entomopathogenic fungus Batkoa major were analyzed using sequences of four genomic regions and evaluated in relation to their genetic diversity, insect hosts and collection site. This entomophthoralean pathogen killed numerous insect species from 23 families and five orders in two remote locations during 2019. The host list of this biotrophic pathogen contains flies, true bugs, butterflies and moths, beetles, and barkflies. Among the infected bugs (Order Hemiptera), the spotted lanternfly (Lycorma delicatula) is a new invasive planthopper pest of various woody plants that was introduced to the USA from Eastern Asia. A high degree of clonality occurred in the studied populations and high gene flow was revealed using four molecular loci for the analysis of population structure. We did not detect any segregation in the population regarding host affiliation (by family or order), or collection site. This is the first description of population structure of a biotrophic fungus-generalist in the entomopathogenic Order Entomophthorales. This analysis aimed to better understand the potential populations of entomopathogen-generalists infecting emerging invasive hosts in new ecosystems.


Subject(s)
Butterflies , Entomophthorales , Hemiptera , Animals , Ecosystem , Fungi , Hemiptera/microbiology , Humans , Insecta , Seasons
10.
Proc Natl Acad Sci U S A ; 117(10): 5134-5143, 2020 03 10.
Article in English | MEDLINE | ID: mdl-32098849

ABSTRACT

Fungi disperse spores to move across landscapes and spore liberation takes different patterns. Many species release spores intermittently; others release spores at specific times of day. Despite intriguing evidence of periodicity, why (and if) the timing of spore release would matter to a fungus remains an open question. Here we use state-of-the-art numerical simulations of atmospheric transport and meteorological data to follow the trajectory of many spores in the atmosphere at different times of day, seasons, and locations across North America. While individual spores follow unpredictable trajectories due to turbulence, in the aggregate patterns emerge: Statistically, spores released during the day fly for several days, whereas spores released at night return to ground within a few hours. Differences are caused by intense turbulence during the day and weak turbulence at night. The pattern is widespread but its reliability varies; for example, day/night patterns are stronger in southern regions. Results provide testable hypotheses explaining both intermittent and regular patterns of spore release as strategies to maximize spore survival in the air. Species with short-lived spores reproducing where there is strong turbulence during the day, for example in Mexico, maximize survival by releasing spores at night. Where cycles are weak, for example in Canada during fall, there is no benefit to releasing spores at the same time every day. Our data challenge the perception of fungal dispersal as risky, wasteful, and beyond control of individuals; our data suggest the timing of spore liberation may be finely tuned to maximize fitness during atmospheric transport.


Subject(s)
Air Microbiology , Air Movements , Seasons , Spores, Fungal/physiology , Atmosphere , Canada , Mexico
11.
Plant Dis ; 103(9): 2237-2245, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31306089

ABSTRACT

Phakopsora pachyrhizi, the causal agent of soybean rust (SBR), is a global threat to soybean production. Since the discovery of SBR in the continental United States, quantitative polymerase chain reaction assays based on the internal transcribed spacer (ITS) ribosomal DNA locus were established for its rapid detection. However, insufficient data were initially available to test assays against factors that could give rise to misidentification. This study aimed to reevaluate current assays for (i) the potential for false-positive detection caused by nontarget Phakopsora species and (ii) the potential for false-negative detection caused by intraspecific variation within the ITS locus of P. pachyrhizi. A large amount of intraspecific and intragenomic variation in ITS was detected, including the presence of polymorphic ITS copies within single leaf samples and within single rust sori. The diagnostic assays were not affected by polymorphisms in the ITS region; however, current assays are at risk of false positives when screened against other species of Phakopsora. This study raises caveats to the use of multicopy genes (e.g., ITS) in single-gene detection assays and discusses the pitfalls of inferences concerning the aerobiological pathways of disease spread made in the absence of an evaluation of intragenomic ITS heterogeneity.


Subject(s)
Genetic Variation , Phakopsora pachyrhizi , Plant Diseases , DNA, Ribosomal Spacer/genetics , Molecular Diagnostic Techniques/standards , Pathology, Molecular , Phakopsora pachyrhizi/genetics , Plant Diseases/microbiology , Glycine max/microbiology , United States
12.
G3 (Bethesda) ; 8(6): 2007-2018, 2018 05 31.
Article in English | MEDLINE | ID: mdl-29674435

ABSTRACT

Phylogenomic approaches have the potential to improve confidence about the inter-relationships of species in the order Mucorales within the fungal tree of life. Rhizopus species are especially important as plant and animal pathogens and bioindustrial fermenters for food and metabolite production. A dataset of 192 orthologous genes was used to construct a phylogenetic tree of 21 Rhizopus strains, classified into four species isolated from habitats of industrial, medical and environmental importance. The phylogeny indicates that the genus Rhizopus consists of three major clades, with R. microsporus as the basal species and the sister lineage to R. stolonifer and two closely related species R. arrhizus and R. delemar A comparative analysis of the mating type locus across Rhizopus reveals that its structure is flexible even between different species in the same genus, but shows similarities between Rhizopus and other mucoralean fungi. The topology of single-gene phylogenies built for two genes involved in mating is similar to the phylogenomic tree. Comparison of the total length of the genome assemblies showed that genome size varies by as much as threefold within a species and is driven by changes in transposable element copy numbers and genome duplications.


Subject(s)
Genomics , Phylogeny , Rhizopus/classification , Rhizopus/genetics , DNA Transposable Elements/genetics , Genes, Mating Type, Fungal , Genome Size , Genome, Fungal , Likelihood Functions , Open Reading Frames/genetics , Species Specificity , Whole Genome Sequencing
13.
Microbiol Spectr ; 5(4)2017 07.
Article in English | MEDLINE | ID: mdl-28710849

ABSTRACT

Dispersal is a fundamental biological process, operating at multiple temporal and spatial scales. Despite an increasing understanding of fungal biodiversity, most research on fungal dispersal focuses on only a small fraction of species. Thus, any discussion of the dispersal dynamics of fungi as a whole is problematic. While abundant morphological and biogeographic data are available for hundreds of species, researchers have yet to integrate this information into a unifying paradigm of fungal dispersal, especially in the context of long-distance dispersal (LDD). Fungal LDD is mediated by multiple vectors, including meteorological phenomena (e.g., wind and precipitation), plants (e.g., seeds and senesced leaves), animals (e.g., fur, feathers, and gut microbiomes), and in many cases humans. In addition, fungal LDD is shaped by both physical constraints on travel and the ability of spores to survive harsh environments. Finally, fungal LDD is commonly measured in different ways, including by direct capture of spores, genetic comparisons of disconnected populations, and statistical modeling and simulations of dispersal data. To unify perspectives on fungal LDD, we propose a synthetic three-part definition that includes (i) an identification of the source population and a measure of the concentration of source inoculum and (ii) a measured and/or modeled dispersal kernel. With this information, LDD is defined as (iii) the distance found within the dispersal kernel beyond which only 1% of spores travel.


Subject(s)
Fungi/physiology , Animals , Biological Evolution , Environment , Fungi/genetics , Plants/microbiology , Seeds/microbiology , Wind
14.
Ann Plast Surg ; 71(4): 342-5, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23797022

ABSTRACT

BACKGROUND: Self-inflicted burns are a multidisciplinary medical challenge. In contrast to the more common motive of attempted suicide in self-infliction of a burn, usually of a serious degree, a second motive is malingering. Motivation of this nature has been exhibited among Israeli soldiers who inflict on themselves low- to moderate-degree burns to obtain dismissal from mandatory military service. The purpose of our study is to investigate and define this phenomenon. METHODS: A retrospective analysis was performed on a population of 75 soldiers admitted to our Medical Center during the year 2010 with the diagnosis of any sort of burn. We set up a database including all relevant information about the burns including date and time of occurrence, cause, body location, depth of burn injury, area and shape of burn, etiology, and prescribed treatment. RESULTS: The summer was found to be the season with the highest incidence of burns. As far as the day of the week was influential, we found that the greater percentage of burns occurred at the beginning of the week. Most of the burns involved a minor surface area on the dorsal aspect of the foot. Scalding with hot water was the most common cause of burn. Eighty-one percent of the burns were atypical, being well demarcated.Most of the burn cases happened at home with no witnesses to the event. Sixty-one percent of the patients were not admitted to the hospital and were conservatively treated. CONCLUSIONS: Israeli soldiers tend to inflict burns on themselves for ulterior motives. Such burns are almost always minor with a small trauma area and sharp demarcations, and hence can be differentiated from other self-inflicted burns described in the literature. We found that most of the burns occur when the soldiers are on vacation at home. This is probably because the privacy allows them to carry out their act undisturbed. It is important to raise the awareness of attending physicians to the characteristics of these burns. Such patients should be evaluated by medical teams including mental health professionals to help them psychologically and to eliminate this unfortunate problem.


Subject(s)
Burns/diagnosis , Malingering/diagnosis , Military Personnel/psychology , Self-Injurious Behavior/diagnosis , Burns/epidemiology , Burns/psychology , Burns/therapy , Humans , Incidence , Israel/epidemiology , Malingering/epidemiology , Malingering/therapy , Retrospective Studies , Self-Injurious Behavior/epidemiology , Self-Injurious Behavior/psychology , Self-Injurious Behavior/therapy
16.
Isr Med Assoc J ; 11(8): 470-3, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19891234

ABSTRACT

BACKGROUND: Due to the absence of accurate tools and appropriate photographic material there is a paucity of objective studies on facial aging in the modern literature. OBJECTIVES: To measure changes in two elements of the face: brow ptosis and cheek mass migration, using an objective tool that we developed which we then used to evaluate facial aging in two subjects studying serial professional photographs over a 25 year period. METHODS: We studied the photographic atlas of the "Brown Sisters," a record of the yearly group photograph of four sisters taken by the photographer Nicolas Nixon. For technical reasons only two of the sisters fulfilled the criteria we set for the study. We used the interpupillary distance of each photograph studied to standardize the brow height and cheek mass distance from the interpupillary line. RESULTS: We observed progressive medial brow descent occurring at about the age of 30, with apparent stabilization thereafter. In contrast, there was a continuous process of lateral brow descent through the years. A process of gradual cheek mass descent was noted in the second half of the third decade. CONCLUSIONS: Our results indicate that the dynamic brow changes start in the second half of the third decade, with more significant lateral brow descent than medial brow descent. The cheek mass reflective point moves in an inferior-lateral direction. The tool we developed can be used to follow aging changes and postoperative results, thereby helping the surgeon achieve true rejuvenation surgery.


Subject(s)
Aging/physiology , Anthropometry/methods , Cheek/anatomy & histology , Forehead/anatomy & histology , Image Processing, Computer-Assisted , Photogrammetry/methods , Adolescent , Adult , Connective Tissue/anatomy & histology , Female , Humans , Longitudinal Studies , Middle Aged , Physiognomy , Reproducibility of Results , Young Adult
18.
Ann Plast Surg ; 54(4): 369-74, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15785274

ABSTRACT

JetPeel (Tav-Tech Ltd., Yehud, Israel) is a new device for cosmetic resurfacing of the facial skin. It uses a new technology of a 2-phase stream that creates a jet composed of gas (oxygen) and microdroplets of fluid (saline) accelerated to supersonic velocities. This jet impacts the skin, causing gentle and accurate cosmetic peeling. Our preclinical and clinical experience with the JetPeel for rejuvenation of the face is presented. In a group of 50 patients, we found the JetPeel technology to be a safe and effective new tool for the usual indications for facial peeling. It was most useful and effective for perioral peel. JetPeel can be used in combination with other resurfacing modalities such as chemical peeling or laser. Further investigation is needed to explore other applications of this technology, such as using different combinations of gases and fluids and transdermal transfer of medication dissolved in the peeling jet.


Subject(s)
Dermabrasion/instrumentation , Face/physiology , Rejuvenation/physiology , Adult , Equipment Design , Esthetics , Female , Humans , Male , Middle Aged , Wound Healing
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