-
Nature Communications Feb 2024Quiescence in stem cells is traditionally considered as a state of inactive dormancy or with poised potential. Naive mouse embryonic stem cells (ESCs) can enter...
Quiescence in stem cells is traditionally considered as a state of inactive dormancy or with poised potential. Naive mouse embryonic stem cells (ESCs) can enter quiescence spontaneously or upon inhibition of MYC or fatty acid oxidation, mimicking embryonic diapause in vivo. The molecular underpinning and developmental potential of quiescent ESCs (qESCs) are relatively unexplored. Here we show that qESCs possess an expanded or unrestricted cell fate, capable of generating both embryonic and extraembryonic cell types (e.g., trophoblast stem cells). These cells have a divergent metabolic landscape comparing to the cycling ESCs, with a notable decrease of the one-carbon metabolite S-adenosylmethionine. The metabolic changes are accompanied by a global reduction of H3K27me3, an increase of chromatin accessibility, as well as the de-repression of endogenous retrovirus MERVL and trophoblast master regulators. Depletion of methionine adenosyltransferase Mat2a or deletion of Eed in the polycomb repressive complex 2 results in removal of the developmental constraints towards the extraembryonic lineages. Our findings suggest that quiescent ESCs are not dormant but rather undergo an active transition towards an unrestricted cell fate.
Topics: Animals; Mice; Embryonic Stem Cells; Cell Differentiation; Chromatin; Mouse Embryonic Stem Cells; Polycomb Repressive Complex 2; S-Adenosylmethionine
PubMed: 38409226
DOI: 10.1038/s41467-024-46121-1 -
Alternative Therapies in Health and... Feb 2024The early symptoms of embryo development arrest are not typical. There is currently no model tool available to predict embryo development arrest.
CONTEXT
The early symptoms of embryo development arrest are not typical. There is currently no model tool available to predict embryo development arrest.
OBJECTIVE
To explore the influencing factors of embryo development arrest in early pregnancy and build a risk prediction model.
METHODS
From May 2019 to March 2023, 277 patients suspected of embryonic development arrest during the first ultrasound examination in the Department of Obstetrics and Gynecology of the Ninth Affiliated Hospital of Soochow University were retrospectively selected as the study subjects. They were divided into diapause group and non-diapause group according to the second ultrasound (review after 1-2 weeks) to diagnose whether embryo development arrest. Collect two sets of data for analysis, Screen out the influencing factors of early pregnancy embryo development arrest. The logistic regression model and random forest model were constructed respectively. Evaluate the predictive performance of two statistical models.
RESULTS
Out of 277 suspected cases of embryonic developmental arrest, 88 were ultimately confirmed. Older age (OR: 2.259, P = .017), higher ultrasonic blood flow resistance index (RI) (OR: 1.728, P = .038), higher ultrasonic gestational sac diameter/embryo head hip length ratio (MSD/CRL) (OR:1.919, P = .007), lower progesterone (OR: 0.562, P = .011), and lower pregnancy-associated protein A (PAPP-A) (OR: 0.495, P = .023). The low expression of vascular endothelial growth factor (VEGF) (OR: 0.618, P = .005) was the influencing factor of embryo development arrest in early pregnancy. Building a prediction model based on the above indicators, it was found through testing that the random forest model is superior to the logistic regression model in predicting the risk of embryo development arrest.
CONCLUSION
A random forest model based on age, ultrasound RI, progesterone, PAPP-A, ultrasound MSD/CRL ratio, and VEGF index can help clinicians identify the risk of embryonic developmental arrest.
PubMed: 38401079
DOI: No ID Found -
Medicina (Kaunas, Lithuania) Jan 2024Cancer is one of the leading causes of death in the world. Various drugs have been developed to eliminate it but to no avail because a tumor can go into dormancy to... (Review)
Review
Cancer is one of the leading causes of death in the world. Various drugs have been developed to eliminate it but to no avail because a tumor can go into dormancy to avoid therapy. In the past few decades, tumor dormancy has become a popular topic in cancer therapy. Recently, there has been an important breakthrough in the study of tumor dormancy. That is, cancer cells can enter a reversible drug-tolerant persister (DTP) state to avoid therapy, but no exact mechanism has been found. The study of the link between the DTP state and diapause seems to provide an opportunity for a correct understanding of the mechanism of the DTP state. Completely treating cancer and avoiding dormancy by targeting the expression of key genes in diapause are possible. This review delves into the characteristics of the DTP state and its connection with embryonic diapause, and possible treatment strategies are summarized. The authors believe that this review will promote the development of cancer therapy.
Topics: Animals; Humans; Diapause; Neoplasms
PubMed: 38399515
DOI: 10.3390/medicina60020228 -
Insects Feb 2024(Okamoto) displays typical adult reproductive diapause under short photoperiods; however, our understanding of the molecular mechanism underlying photoperiod-sensitive...
(Okamoto) displays typical adult reproductive diapause under short photoperiods; however, our understanding of the molecular mechanism underlying photoperiod-sensitive reproduction remains limited. In this study, we performed transcriptome profiling of four treatments (the diapause-sensitive stage and pre-diapause phase under long and short photoperiods) of using RNA sequencing (RNA-seq). A total of 71,654 unigenes were obtained from the samples. Enrichment analysis showed that fatty acid metabolism-related pathways were altered under a short photoperiod. Moreover, β-oxidation-related gene expression was active during the diapause-sensitive period under a short photoperiod. The knockdown of juvenile hormone acid methyltransferase 1 () prolonged the pre-oviposition period but did not affect the reproductive ability of female individuals in . These findings provided us with a more comprehensive understanding of the molecular mechanisms of photoperiod-sensitive diapause and show that groundwork is crucial for bolstering the long-term storage and biocontrol potential of .
PubMed: 38392555
DOI: 10.3390/insects15020136 -
Journal of Insect Science (Online) Jan 2024The spotted amber ladybird, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae), is known to be a potent predator of aphids, psyllids, whiteflies, mealybugs, and...
The spotted amber ladybird, Hippodamia variegata (Goeze) (Coleoptera: Coccinellidae), is known to be a potent predator of aphids, psyllids, whiteflies, mealybugs, and some butterfly species. This ladybeetle overwinters in the diapausing adult stage. The current study aimed to evaluate the impact of diapause on the energy resources and cuticular hydrocarbons (CHCs) of the female ladybeetle, specifically comparing the changes in glycogen, lipid, and protein contents, and CHCs profile of diapausing and non-diapausing adults. In this study, gas chromatography-mass was used to analyze whole-body extracts of the beetles. Results showed no significant differences between the amount of glycogen, lipid, and protein contents of diapausing and non-diapausing ladybeetle. The CHCs profile of H. variegata consisted of 24 hydrocarbons categorized into 2 groups: linear aliphatic hydrocarbons (n-alkanes) and methyl-branched hydrocarbons (17 molecules), as well as unsaturated cyclic compounds (7 molecules). The n-alkanes, with 14 compounds, were identified as the primary constituents of the CHCs of the ladybeetle. Six molecules were common to non-diapausing and diapausing beetles, 5 were exclusive to non-diapausing beetles, and 13 were exclusive to diapausing beetles. Moreover, we noted a significant difference in the quantity and quality of CHCs between diapausing and non-diapausing beetles, with diapausing beetles synthesizing more CHCs with longer chains. This disparity in CHC profiles was concluded to be an adaptation of H. variegata to survive harsh environmental conditions during diapause.
Topics: Female; Animals; Diapause, Insect; Hydrocarbons; Coleoptera; Alkanes; Diapause; Glycogen; Lipids
PubMed: 38387433
DOI: 10.1093/jisesa/ieae005 -
Journal of Medical Entomology May 2024In temperate regions of the United States, female Anopheles mosquitoes respond to low temperatures and short photoperiods by entering an overwintering dormancy or...
In temperate regions of the United States, female Anopheles mosquitoes respond to low temperatures and short photoperiods by entering an overwintering dormancy or diapause. Diapause in Anopheles results in reduced frequency of blood-feeding and reproductive arrest, indicating a period when pathogen transmission by these mosquitoes is unlikely. However, it is unclear precisely how late into the fall and how early in the spring these mosquitoes are biting, reproducing, and potentially transmitting pathogens. This is further complicated by the lack of clear markers of diapause in Anopheles (e.g., changes in egg follicle length). Our goal was to characterize the seasonal reproductive activity of female Anopheles in central Ohio, United States and evaluate egg follicle length as an indicator of Anopheles diapause. We used traditional mosquito traps and aspirators to collect Anopheles from urban woodlots and culverts, respectively, from late September 2021 through mid-May 2022 in central Ohio. By measuring their egg follicle length, reproductive status, and blood-feeding status, we found that egg follicle length is not a reliable indicator of Anopheles diapause. We also found that a small proportion of An. punctipennis (Say), An. perplexens (Ludlow), and An. quadrimaculatus (Say) continued to bite and reproduce into early November 2021 and that females of these species terminated reproductive dormancy and began biting by mid-March 2022. This period of reproductive activity extends beyond current mosquito surveillance and control in Ohio. Our findings suggest that within temperate regions of North America, Anopheles have the capacity to transmit pathogens throughout the spring, summer, and fall.
Topics: Animals; Anopheles; Seasons; Female; Diapause, Insect; Reproduction; Ohio
PubMed: 38387012
DOI: 10.1093/jme/tjae024 -
Ecology and Evolution Feb 2024Global warming is affecting the phenological cycles of plants and animals, altering the complex synchronization that has co-evolved over thousands of years between...
Global warming is affecting the phenological cycles of plants and animals, altering the complex synchronization that has co-evolved over thousands of years between interacting species and trophic levels. Here, we examined how warmer winter conditions affect the timing of budburst in six common European trees and the hatching of a generalist leaf-feeding insect, the spongy moth , whose fitness depends on the synchrony between egg hatch and leaf emergence of the host tree. We applied four different temperature treatments to eggs and twig cuttings, that mimicked warmer winters and reduced chilling temperatures that are necessary for insect diapause and bud dormancy release, using heated open-top chambers (ambient or +3.5°C), and heated greenhouses (maintained at >6°C or >10°C). In addition, we conducted preference and performance tests to determine which tree species the larvae prefer and benefit from the most. Budburst success and twig survival were highest for all tree species at ambient temperature conditions, whereas it declined under elevated winter temperature for and , likely due to a lack of chilling. While egg hatch coincided with budburst in most tree species within 10 days under ambient conditions, it coincided with budburst only in , , and, to a lesser extent, under warmer conditions. With further warming, we, therefore, expect an increasing mismatch in trees with high chilling requirements, such as and , but still good synchronization with trees having low chilling requirements, such as and . Surprisingly, first instar larvae preferred and gained weight faster when fed with leaves of , while ranked second. Our results suggest that spongy moth outbreaks are likely to persist in oak and hornbeam forests in western and central Europe.
PubMed: 38371870
DOI: 10.1002/ece3.10928 -
Current Research in Insect Science 2024Diapause is a form of internally-controlled dormancy that allows insects to avoid stressful conditions and periods of low food availability. Eastern spruce budworm (...
Diapause is a form of internally-controlled dormancy that allows insects to avoid stressful conditions and periods of low food availability. Eastern spruce budworm ( Clemens), like many cold-adapted insects, enter diapause well in advance of winter conditions, thus exposing them to elevated temperatures during fall that can deplete energy stores and impact post-diapause survival. We explored the impact of fall conditions on by manipulating the length of the fall period and exposure temperatures during the diapause initiation phase of second instar larvae in a factorial design. We exposed second instar larvae to four fall temperatures (10, 15, 20, and 25°C) and five exposure times (1, 2, 4, 6, and 10 weeks) prior to standardized diapause conditions. We measured metabolites (glycogen, glycerol, and protein) prior to and during diapause for a subset of individuals. We also measured post-diapause survival by quantifying emergence following diapause conditions for a subset of individuals. We found that long, warm fall conditions depleted glycogen content and lowered post-diapause survival. We also found that short, cool conditions impacted post-diapause survival, although glycogen content remained high. Our results showed that fall conditions have substantial fitness consequences to overwintering insects. Optimal fall conditions struck a balance between exposure time and temperature. Our findings point to a potentially adaptive reason for early diapause onset: that an undescribed, but temperature-sensitive process is occurring in larvae during the diapause initiation period that is essential for overwintering survival and successful post-diapause emergence.
PubMed: 38371385
DOI: 10.1016/j.cris.2024.100073 -
Proceedings. Biological Sciences Feb 2024Understanding mechanisms that promote the maintenance of biodiversity (genetic and species diversity) has been a central topic in evolution and ecology. Previous studies...
Understanding mechanisms that promote the maintenance of biodiversity (genetic and species diversity) has been a central topic in evolution and ecology. Previous studies have revealed that diapause can contribute to coexistence of competing genotypes or species in fluctuating environments via the storage effect. However, they tended to focus on differences in reproductive success (e.g. seed yield) and diapause termination (e.g. germination) timing. Here we tested whether different photoperiodic responses in diapause induction can promote coexistence of two parthenogenetic (asexual) genotypes of in Lake Fukami-ike, Japan. Through laboratory experiments, we confirmed that short day length and low food availability induced the production of diapausing eggs. Furthermore, we found that one genotype tended to produce diapausing eggs in broader environmental conditions than the other. Terminating parthenogenetic reproduction earlier decreases total clonal production, but the early diapausing genotype becomes advantageous by assuring reproduction in 'short' years where winter arrival is earlier than usual. Empirically parameterized theoretical analyses suggested that different photoperiodic responses can promote coexistence via the storage effect with fluctuations of the growing season length. Therefore, timing of diapause induction may be as important as diapause termination timing for promoting the maintenance of genetic diversity in fluctuating environments.
Topics: Animals; Daphnia pulex; Circadian Rhythm; Photoperiod; Diapause; Genetic Variation; Daphnia
PubMed: 38351804
DOI: 10.1098/rspb.2023.1860 -
Environmental Entomology Apr 2024Cold winter temperatures govern the distribution and abundance of many insect species, but refugia that provide microclimates can moderate temperature-driven mortality....
Cold winter temperatures govern the distribution and abundance of many insect species, but refugia that provide microclimates can moderate temperature-driven mortality. Winter temperatures have been implicated in limiting the survival and range of Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae; redbanded stink bug), an economically damaging invasive pest in the southeastern United States, but the role of refugia in overwintering survival of this pest is poorly understood. We conducted 2 studies in successive years to evaluate how leaf litter from hardwoods, pines, and soybeans modulate overwintering site selection and survival of P. guildinii. In the second-year study, we also quantified the buffering effect of the 3 leaf litter types compared to ambient conditions and assessed diapause. In the first-year study, we found that stink bugs preferentially dispersed into leaf litter compared with remaining unsheltered on bare soil; no clear preference among leaf litter types was found. In the second year, however, no clear differences were found among leaf litter types and bare soil. Means of daily minimum temperatures under leaf litter were at least 3.0 ± 0.9 °C (SE) warmer and generally less variable than ambient conditions. While high mortality in both studies illustrates that more work must be done to fully understand overwintering survival, limited survival through potentially lethal conditions in the first-year study nonetheless emphasizes the possibility of populations persisting and rebounding in the following spring. Furthermore, our study highlights the potential for stink bugs to persist in areas with lethal ambient temperatures by dispersing into widely available substrates.
Topics: Animals; Glycine max; Microclimate; Heteroptera; Cold Temperature; Soil
PubMed: 38334261
DOI: 10.1093/ee/nvae001