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Human Reproduction (Oxford, England) Oct 2021How are germ cell numbers and initiation of folliculogenesis affected in fetal Turner syndrome (TS) ovaries?
STUDY QUESTION
How are germ cell numbers and initiation of folliculogenesis affected in fetal Turner syndrome (TS) ovaries?
SUMMARY ANSWER
Germ cell development was severely affected already in early second trimester pregnancies, including accelerated oogonia loss and impaired initiation of primordial follicle formation in TS ovaries, while the phenotype in TS mosaic ovaries was less severe.
WHAT IS KNOWN ALREADY
Females with TS are characterized by premature ovarian insufficiency (POI). This phenotype is proposed to be a consequence of germ cell loss during development, but the timing and mechanisms behind this are not characterized in detail. Only few studies have evaluated germ cell development in fetal TS and TS mosaic ovaries, and with a sparse number of specimens included per study.
STUDY DESIGN, SIZE, DURATION
This study included a total of 102 formalin-fixed and paraffin-embedded fetal ovarian tissue specimens. Specimens included were from fetuses with 45,X (N = 42 aged gestational week (GW) 12-20, except one GW 40 sample), 45,X/46,XX (N = 7, aged GW 12-20), and from controls (N = 53, aged GW 12-42) from a biobank (ethics approval # H-2-2014-103).
PARTICIPANTS/MATERIALS, SETTING, METHODS
The number of OCT4 positive germ cells/mm2, follicles (primordial and primary)/mm2 and cPARP positive cells/mm2 were quantified in fetal ovarian tissue from TS, TS mosaic and controls following morphological and immunohistochemical analysis.
MAIN RESULTS AND THE ROLE OF CHANCE
After adjusting for gestational age, the number of OCT4+ oogonia was significantly higher in control ovaries (N = 53) versus 45,X ovaries (N = 40, P < 0.001), as well as in control ovaries versus 45,X/46,XX mosaic ovaries (N = 7, P < 0.043). Accordingly, the numbers of follicles were significantly higher in control ovaries versus 45,X and 45,X/46,XX ovaries from GW 16-20 with a median range of 154 (N = 11) versus 0 (N = 24) versus 3 (N = 5) (P < 0.001 and P < 0.015, respectively). The number of follicles was also significantly higher in 45,X/46,XX mosaic ovaries from GW 16-20 compared with 45,X ovaries (P < 0.005). Additionally, the numbers of apoptotic cells determined as cPARP+ cells/mm2 were significantly higher in ovaries 45,X (n = 39) versus controls (n = 15, P = 0.001) from GW 12-20 after adjusting for GW.
LIMITATIONS, REASONS FOR CAUTION
The analysis of OCT4+ cells/mm2, cPARP+ cells/mm2 and follicles (primordial and primary)/mm2 should be considered semi-quantitative as it was not possible to use quantification by stereology. The heterogeneous distribution of follicles in the ovarian cortex warrants a cautious interpretation of the exact quantitative numbers reported. Moreover, only one 45,X specimen and no 45,X/46,XX specimens aged above GW 20 were available for this study, which unfortunately made it impossible to assess whether the ovarian folliculogenesis was delayed or absent in the TS and TS mosaic specimens.
WIDER IMPLICATIONS OF THE FINDINGS
This human study provides insights about the timing of accelerated fetal germ cell loss in TS. Knowledge about the biological mechanism of POI in girls with TS is clinically useful when counseling patients about expected ovarian function and fertility preservation strategies.
STUDY FUNDING/COMPETING INTEREST(S)
This work was supported by the International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC).
TRIAL REGISTRATION NUMBER
N/A.
Topics: Aged; Female; Fetal Development; Humans; Male; Oogonia; Ovarian Follicle; Ovary; Pregnancy; Turner Syndrome
PubMed: 34568940
DOI: 10.1093/humrep/deab210 -
Plant Disease Oct 2023In 2021 and 2022, wilt symptoms were observed in lettuce ( L.) fields in Yuma County, Arizona (AZ). Incidence was < 1% at all locations. Symptoms included stunting,...
In 2021 and 2022, wilt symptoms were observed in lettuce ( L.) fields in Yuma County, Arizona (AZ). Incidence was < 1% at all locations. Symptoms included stunting, yellowing and wilting of outer leaves. As disease progressed, outer leaves wilted and turned necrotic. In advanced stages, tap roots turned brown-gray, with few feeder roots. The crown remained intact until the plant collapsed. Symptomatic romaine and iceberg plants were collected from two sites. Necrotic roots were washed and then plated on amended corn meal agar (PARP) (Kannwischer et al. 1978). After 2-3 days, slow growing, coenocytic, submerged mycelia grew from these pieces. In culture, profuse oogonia formed with diameters of 30-39 (avg. = 33.7) µm and spiny protuberances (5-8 [avg. = 6.4] µm long) with thickened bases. Oospores were spherical and aplerotic, with diameters of 25-32 (avg. = 27.8) µm. Lettuce with identical symptoms from the Salinas Valley, California (CA) were also tested and similar isolates were recovered. Pathogenicity was tested using six AZ and one CA isolates. Inoculum was grown on barley seeds moistened with sterile distilled water, autoclaved three times (at 24 h intervals), then inoculated with colonized agar plugs and incubated at 20°C. Inoculum was used after two weeks. For each isolate, 12 3-week-old iceberg (cv. Speedway) and romaine (cv. Del Sol) plants were inoculated by placing 3-4 colonized barley seed next to the roots of the potted plants. Plants were maintained in a greenhouse at 24-26°C (daytime high) with ambient light. After eight days, all inoculated plants exhibited chlorotic lower leaves that later wilted. Both feeder roots and taproots showed brown-gray discoloration and were necrotic. Microscopy showed the presence of spiny oogonia in inoculated roots. Symptoms caused by the AZ and CA isolates were indistinguishable from each other. Isolations from necrotic tissue resulted in colonies morphologically identical to the original isolates. Twelve control plants inoculated with uncolonized barley seed developed no symptoms. DNA was extracted from all seven AZ and CA isolates pre-inoculation, and AZ isolate 2 recovered from both lettuce types post-inoculation for molecular characterization. The internal transcribed spacer (ITS) and cytochrome C oxidase subunit 2 (COX II) were amplified for the above isolates using primer sets ITS1/ITS4 (White et al. 1990) and FM66/FM58 (Villa et al. 2006), then sequenced. ITS of pre- and post-inoculated isolates for AZ (OQ054806 and OQ054807) and CA (OQ564388) matched 1078/1078 bases of (syn. ; AY598712.2) with 99.8% identity. There were two SNPs in COX II for AZ isolate 1 (OR069239); all other isolates pre- and post- inoculation for AZ (OR069240 and OR069242) and CA (OR069241) uniformly matched 533/535 bases of (KJ595385.1) with 99.4% identity. Based on these molecular and morphological data, the isolates were identified as (Blok and Van Der Plaats-Niterink 1978; Van Der Plaats-Niterink 1981). To our knowledge, this is the first report of on lettuce in AZ. Designated as Pythium wilt, this disease is reported on lettuce in The Netherlands (Blok and Van Der Plaats-Niterink 1978), Japan (Matsuura, et al. 2010), and CA (Davis, et al. 1995). Arizona is an important lettuce growing region; if this disease becomes more prevalent, lettuce production in this region could be negatively impacted.
PubMed: 37822102
DOI: 10.1094/PDIS-03-23-0472-PDN -
Reproduction (Cambridge, England) Jul 2023Fanconi anemia results in subfertility and germ cell deficiency in women. We present histological and RNA-seq analysis of Fance-deficient primordial germ cells to...
IN BRIEF
Fanconi anemia results in subfertility and germ cell deficiency in women. We present histological and RNA-seq analysis of Fance-deficient primordial germ cells to explore the possible mechanisms of their progressive depletion.
ABSTRACT
Primordial germ cells (PGCs) development is a subtle and complex regulatory process. Fance is an important substrate molecule necessary for the activation of the Fanconi anemia pathway, and its homozygous mutant causes massive oogonia loss as early as embryonic day 13.5 (E13.5). Here, we present histological and RNA-seq analysis of Fance-deficient PGCs to explore the possible mechanisms responsible for its progressive depletion of germ cells. In Fance-/- embryos, the reduction of PGCs was already evident at E9.5 and the progressive loss of PGCs led to the PGCs being almost exhausted at E12.5. An increase of apoptotic cells was detected among Fance-/- PGCs, which may intuitively explain their reduced number in embryos. Moreover, abnormal cell proliferation and accumulating DNA damage were detected in E12.5 Fance-/- PGCs. We identified 3026 differentially expressed genes in E12.5 Fance-/- PGCs compared to Fance+/+. KEGG pathway analysis revealed that the upregulated genes were highly associated with 'lysosome', and various metabolism pathways, whereas the downregulated genes were mainly enriched in 'cell cycle', 'oocyte meiosis', 'ribosome', and various DNA repair pathways. In addition, multiple genes of various cell death pathways were found to be differentially expressed in E12.5 Fance-/- PGCs, indicating that PGCs death in Fance-/- embryos might diverge from canonical apoptosis. These findings indicate that Fance is essential for PGCs survival and the potential mechanisms involve cell cycle regulation, DNA damage repair, cell death prevention, and by regulating lysosome and ribosome function. Our results provide an important reference for further studies.
Topics: Female; Humans; Cell Differentiation; DNA Repair; Fanconi Anemia; Germ Cells; Transcriptome
PubMed: 37184052
DOI: 10.1530/REP-23-0038 -
Journal of Phycology Jun 2021Monoecy and parthenogenesis exist in certain male and female gametophytes of the brown alga Undaria pinnatifida. The inheritance of these traits is not known. In this...
The Inheritable Characteristics of Monoecy and Parthenogenesis Provide A Means for Establishing A Doubled Haploid Population in the Economically Important Brown Alga Undaria pinnatifida (Laminariales, Alariaceae).
Monoecy and parthenogenesis exist in certain male and female gametophytes of the brown alga Undaria pinnatifida. The inheritance of these traits is not known. In this study, we made a cross between a male and a female gametophyte clone which could exhibit monoecy and parthenogenesis phenotypes, respectively, and obtained their next-generation gametophyte offspring. We found that under conditions suitable for gametogenesis, all of the male offspring (n = 100) exhibited monoecy phenotype and all of the female offspring (n = 100) only formed oogonia and underwent parthenogenesis, suggesting that monoecy and parthenogenesis phenotypes are inheritable. Then, we established a doubled haploid (DH) population through monoecious selfing and parthenogenesis, and evaluated the young sporophyte growth and the maximum quantum yield (F /F ) of 10 "male" and 10 "female" DH lines. On day 60, the average length of the "male" DH lines was significantly larger than that of the "female" DH lines, while their average F /F values were not significantly different. Monoecious selfing seemed superior to parthenogenesis as the sporophyte formation efficiency, and the young sporophyte growth was better in the former than in the latter. We also crossed two monoecious gametophytes with another male gametophyte, and a parentage analysis showed success of obtaining hybrid sporophytes, indicating that the female gametes released by the monoecious gametophyte can actually be fertilized by sperm. The approach of establishing a DH population proposed here will be useful in genetic breeding and quantitative trait loci mapping in U. pinnatifida and may be applicable to other kelp species.
Topics: Haploidy; Kelp; Parthenogenesis; Phaeophyceae; Undaria
PubMed: 33624318
DOI: 10.1111/jpy.13153 -
Communications Biology Oct 2023The northern white rhinoceros is functionally extinct with only two females left. Establishing methods to culture ovarian tissues, follicles, and oocytes to generate...
The northern white rhinoceros is functionally extinct with only two females left. Establishing methods to culture ovarian tissues, follicles, and oocytes to generate eggs will support conservation efforts using in vitro embryo production. To the best of our knowledge, this is the first description of the structure and molecular signature of any rhinoceros, more specifically, we describe the neonatal and adult southern white rhinoceros (Ceratotherium simum simum) ovary; the closest relation of the northern white rhinoceros. Interestingly, all ovaries contain follicles despite advanced age. Analysis of the neonate reveals a population of cells molecularly characterised as mitotically active, pluripotent with germ cell properties. These results indicate that unusually, the neonatal ovary still contains oogonia in germ cell nests at birth, providing an opportunity for fertility preservation. Therefore, utilising ovaries from stillborn and adult rhinoceros can provide cells for advanced assisted reproductive technologies and investigating the neonatal ovaries of other endangered species is crucial for conservation.
Topics: Animals; Female; Ovary; Oogonia; Oocytes; Endangered Species; Perissodactyla
PubMed: 37848538
DOI: 10.1038/s42003-023-05256-5 -
Frontiers in Microbiology 2021Black pod disease, caused by species, is among the main limiting factors of cacao ( L.) production. High incidence levels of black pod disease have been reported in...
Black pod disease, caused by species, is among the main limiting factors of cacao ( L.) production. High incidence levels of black pod disease have been reported in Brazil, being induced by , , , and . To assess the diversity of species affecting cacao in Brazil, 40 new isolates were obtained from cacao pods exhibiting symptoms of black pod disease collected in different smallholder farms in 2017. Further, ten cacao-infecting isolates morphologically identified as and were molecularly characterized. The genomic regions beta-tubulin, elongation factor 1 alpha, heat shock protein 90, and internal transcribed spacer, and the mitochondrially encoded cytochrome oxidase I and II genes were PCR-amplified and Sanger-sequenced from the cacao-infecting isolates. The morphological characterization and evaluation of the mycelial growth rates for the isolates were performed . Based on the molecular analysis and morphological comparisons, 19 isolates were identified as (clade 4). Interestingly, 31 isolates grouped together in the phylogenetic tree and were placed apart from previously known species in clade 2. Therefore, these isolates are considered as a new species herein referred to as sp. nov., which produced papillate, semipapillate, and persistent sporangia on simple sporangiophores. The isolates were identified as A1 mating type by pairing each isolate with known A1 and A2 tester strains of , but no oogonia/antheridia were observed when was paired with the different tester strains. The and isolates showed higher mycelial growth rates, when compared to , on different media at 10, 15, and 20°C, but similar values were observed when grown on clarified CA media at 25 and 30°C. The pathogenicity tests carried out on pods of four cacao clones (CCN51, PS1319, Cepec2004, and CP49) showed significant variability among the isolates of both species, with inducing higher rates of necrotic lesion expansion, when compared to . Here, two species were found associated with black pod disease in the state of Bahia, Brazil, and the previously undescribed seems to be prevalent in field conditions. This is the first report of on . Also, these findings are crucial to improve the disease control strategies, and for the development of cacao materials genetically resistant to .
PubMed: 33815301
DOI: 10.3389/fmicb.2021.537399 -
Scientific Reports Dec 2021In vitro gonad culture systems have proven useful to investigate intrinsic mechanisms of sexual reproduction in animals. Here we describe development of an in vitro...
In vitro gonad culture systems have proven useful to investigate intrinsic mechanisms of sexual reproduction in animals. Here we describe development of an in vitro culture method for coral ovaries. Mesenterial tissues containing both ovaries and mesenterial filaments were microscopically isolated from the scleractinian coral, Fimbriaphyllia ancora, and culture conditions were optimized. M199 diluted 10× (10% M199, pH 8.1) and supplemented with 25 mM HEPES and the antibiotics, ampicillin, penicillin and streptomycin, supported oocyte survival and maintained the structural integrity of ovaries during short-term culture (~ 6 days). Addition of a commercial antibiotic-antimycotic solution (Anti-Anti) and fetal bovine serum adversely affected ovary maintenance and caused tissue disintegration. Characterization of cultured ovaries showed that there is no difference in cell proliferation of ovarian somatic cells between culture Days 1 and 6. Moreover, the presence of oogonia and expression of a major yolk protein, vitellogenin, were confirmed in ovaries cultured for 6 days. This system will be useful for studying effects of a wide range of substances on coral oogenesis.
Topics: Animals; Anthozoa; Female; In Vitro Techniques; Oocytes; Oogenesis; Ovary; Tissue Culture Techniques; Vitellogenins
PubMed: 34934168
DOI: 10.1038/s41598-021-03810-x -
Chromosoma Mar 2016The MRE11 complex (MRE11, RAD50, and NBS1) is a central component of the DNA damage response, governing both double-strand break repair and DNA damage response...
The MRE11 complex (MRE11, RAD50, and NBS1) is a central component of the DNA damage response, governing both double-strand break repair and DNA damage response signaling. To determine the functions of the MRE11 complex in the development and maintenance of oocytes, we analyzed ovarian phenotypes of mice harboring the hypomorphic Mre11 (ATLD1) allele. Mre11 (ATLD1/ATLD1) females exhibited premature oocyte elimination attributable to defects in homologous chromosome pairing and double-strand break repair during meiotic prophase. Other aspects of meiotic progression, including attachment of telomeres to the nuclear envelope and recruitment of RAD21L, a component of the meiotic cohesin complex to the synaptonemal complex, were normal. Unlike Dmc1 (-/-) and Trp13 (Gt/Gt) mice which exhibit comparable defects in double-strand break repair and oocyte depletion by 5 days post-partum, we found that oocyte attrition occurred by 12 weeks in Mre11 (ATLD1/ATLD1) . Disruption of the oocyte checkpoint pathway governed by Chk2 gene further enhanced the survival of Mre11 (ATLD1/ATLD1) follicles. Together our data suggest that the MRE11 complex influences the elimination of oocytes with unrepaired meiotic double-strand breaks post-natally, in addition to its previously described role in double-strand break repair and homologous synapsis during female meiosis.
Topics: Animals; Chromosome Pairing; DNA; DNA Breaks, Double-Stranded; DNA Repair; DNA Repair Enzymes; DNA-Binding Proteins; Female; MRE11 Homologue Protein; Meiosis; Mice; Mice, Transgenic; Oocytes; Oogenesis; Oogonia
PubMed: 26232174
DOI: 10.1007/s00412-015-0535-8 -
Plant Disease Sep 2023Tobacco (Nicotiana tabacum L.) is an important economic crop that is widely grown around the world. Its annual production in China is estimated at 2.2 million tons...
Tobacco (Nicotiana tabacum L.) is an important economic crop that is widely grown around the world. Its annual production in China is estimated at 2.2 million tons (Berbeć and Matyka 2020). Since 2022, a root rot disease was sporadically observed on tobacco seedlings on cultivar Yunyan 87 in cultivated tobacco fields in the Hunan province of China. A disease incidence of about 10% occurred across 48 ha of tobacco fields. The affected tobacco plants had slow and stunted growth with yellowing leaves. The roots turned grayish brown, decayed, and died. Diseased roots were collected from six fields and cut into small pieces (5 mm ×5 mm) from the edge of the rotted portions, and then sterilized with 70% ethanol for 10 s, 0.1% HgCl2 for 1 min, and washed in sterilized water three times. All the sterilized tissue were placed on potato dextrose agar (PDA) medium and cultured at 26 ℃ in the dark. About 3 days later, colonies with similar morphology were removed and sub-cultured on fresh PDA. A total of six strains were obtained from six tobacco samples. Strains were white and had radial growth on PDA. Hyphae were aseptate and the sporangia were filamentous. The oogonia were subglobose, smooth, 16.04 ± 0.25 µm (n=50) in diameter, and developed on unbranched stalks. The antheridia were barrel shaped and clavate. Oospores were globose, aplerotic or nearly plerotic, measuring 6.62 ± 0.33 µm (n=50). These morphological characteristics were consistent with the description of Pythium spp. (van der Plaats-Niterink 1981). For molecular identification, the internal transcribed spacer (ITS) region of rDNA and cytochrome c oxidase subunit I (Cox I) of a representative isolate, GF-3, were amplified and sequenced (GenBank accession nos. OR228424 for ITS and OR237556 for Cox I) using universal primers ITS1/ITS4 (White et al. 1990) and FM58/FM66, respectively (Villa et al. 2006). BLASTn analysis revealed that the ITS and Cox I sequences were 99.76 % (838/840 bp) and 99.85% (671/672 bp) identical to the corresponding sequences of P. dissotocum strain CBS 166.68 (AY598634.2) and UM982 (MT981147.1), respectively. A neighbor-joining phylogenetic tree based on the Cox I sequence showed that GF-3 grouped in the P. dissotocum branch. Based on morphological and molecular characteristics, GF-3 was identified to be P. dissotocum. For pathogenicity testing, four- to five-leaf-old healthy potted tobacco seedlings of the Yunyan 87 cultivar were inoculated with a zoospore suspension (1 × 105 zoospores/ml), which was induced on V8-juice medium. The zoospore suspension was introduced into the soil around plant roots and 10 mL of inoculum was used for each plant. In the control group, plants were inoculated with sterilized water. All of the treated plants were kept in humid chambers at 26°C under a 12 h/12 h photoperiod. The pathogenicity assays were performed twice, with each treatment having three replicated plants. After 5 days, tobacco seedlings inoculated with P. dissotocum showed symptoms resembling that observed in the field. However, the control plants remained healthy. Pythium dissotocum was re-isolated from the infected plants and identified by morphological and molecular methods, thus confirming Koch's postulates. Pythium dissotocum has been reported causing root rot in other plants, including hydroponic lettuce (McGehee et al. 2018) and spinach (Huo et al. 2020). Also, many Pythium species have recently been recovered from float-bed tobacco transplant production greenhouses (Zhang et al. 2022). However, to our knowledge, this is the first report of root rot on tobacco caused by P. dissotocum in China. Since this disease could greatly affect tobacco seedling establishment in the field, appropriate management strategies need to be developed to reduce further losses in tobacco planting fields.
PubMed: 37732900
DOI: 10.1094/PDIS-07-23-1303-PDN -
Theriogenology Aug 2017Astyanax altiparanae is a Brazilian species of substantial commercial, environmental and scientific importance; however, existing studies on its reproduction do not seem...
Astyanax altiparanae is a Brazilian species of substantial commercial, environmental and scientific importance; however, existing studies on its reproduction do not seem to provide enough details. In light of the increasing use of this species in fish farming and the need for basic studies for the development of new production technologies, we describe the structural and ultrastructural characteristics of the ovaries of A. altiparanae, and characterize the species' reproductive cycle. Females were collected monthly from March 2013 to February 2014, and reproductive management began in October 2013. The ovaries were removed, fixed in Karnovsky's fixative, and prepared for light microscopy, transmission electron microscopy and immunohistochemistry anti-PCNA. These techniques enabled us to characterize the ovaries, the germ cells, and the somatic cells in detail, as well as their changes over time. The reproductive cycle was characterized based on the monthly variation in the gonadosomatic ratio, the proportion of germ cells, and the rate of oogonium proliferation. The macroscopic analysis of the ovaries suggests that the vascularization pattern and color of the ovaries vary according to development. There are new types of analyses that can be applied even in the fish farming industry, such as a comparison between ovaries staining and weight or the frequency distribution of these colors throughout the year. This study also provides details on microscopic characteristics that have never before been reported for species of Astyanax, such as the presence of annulate lamellae in oogonia, the development of the zona pellucida from oocytes in the one-nucleolus step, and the development of the micropylar apparatus in oocytes in the cortical alveolar step. When the reproductive cycle was analyzed, this species was found to have a long period of spawning, with a reproductive peak from October to February and multiple spawning events, confirming the period already described in the literature. Variations in reproductive periods and the ability to reproduce in lentic environments suggest that A. altiparanae has the ability to respond quickly to environmental changes and exhibits high reproductive flexibility. All of these characteristics confirm the great potential of this species in the fish farming industry.
Topics: Animals; Aquaculture; Characiformes; Female; Ovary; Periodicity; Reproduction; Sexual Maturation
PubMed: 28601145
DOI: 10.1016/j.theriogenology.2017.04.044