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Theriogenology Dec 2023Although the negative effect of maternal exposure to heat stress on production and reproduction of offspring has been reported, there are some discrepancies among...
Developmental programming of production and reproduction in dairy cows: II. Association of gestational stage of maternal exposure to heat stress with offspring's birth weight, milk yield, reproductive performance and AMH concentration during the first lactation period.
Although the negative effect of maternal exposure to heat stress on production and reproduction of offspring has been reported, there are some discrepancies among various studies about which gestational stage is more critical in this regard. Therefore, the present research was conducted to identify during which stage(s) of pregnancy maternal exposure to heat stress would lead to more dramatic decrease in productive and reproductive performance of offspring. To this end, offspring were classified based on the gestational stage they were in utero exposed to heat stress into four categories, including heat stress exposure (HSE) during only the first trimester of gestation (HSE1), HSE during the first and second trimester of gestation (HSE2), HSE during the second and third trimester of gestation (HSE3) and HSE during only the third trimester of gestation (HSE4). In study I, data of birth weight, milk yield and reproductive variables of 11,788 offspring and data of the month they were conceived were retrieved. In study II, blood samples (n = 521) were collected from offspring in various categories of HSE for measurement of serum AMH. Offspring in HSE1 and HSE2 categories were heavier than offspring in HSE3 and HSE4 categories (P < 0.0001). Offspring in HSE1 and HSE3 categories had the lowest and highest milk production, respectively (P < 0.05). First service conception rate was the greatest and worst in HSE1 and HSE4 categories, respectively (P < 0.05). Service per conception and calving to conception interval were greater in HSE2 than HSE4 category (P < 0.05). Concentration of AMH was lower in HSE1 than HSE4 category (P < 0.05). In conclusion, the present study indicated that the early stage of gestation could be a more critical period for the negative impact of in utero heat stress on developmental programming of milk production and ovarian reserves. Yet an evident temporal pattern for the adverse effect of maternal heat stress on developmental programming of reproductive performance in offspring was not found.
PubMed: 37690376
DOI: 10.1016/j.theriogenology.2023.09.002 -
The Biological Bulletin Aug 2023AbstractColonial animals are composed of clonal individuals that remain physically connected and physiologically integrated. Salps are tunicates with a dual life cycle,...
AbstractColonial animals are composed of clonal individuals that remain physically connected and physiologically integrated. Salps are tunicates with a dual life cycle, including an asexual solitary stage that buds sexual colonies composed of jet-propelling zooids that efficiently swim together as a single unit by multijet propulsion. Colonies from different species develop distinct architectures characterized by their zooid arrangement patterns, but this diversity has received little attention. Thus, these architectures have never been formally defined using a framework of variables and axes that would allow comparative analyses. We set out to define an ontology of the salp colony architecture morphospace and describe the developmental pathways that build the different architectures. To inform these definitions, we collected and photographed live specimens of adult and developing colonies through offshore scuba diving. Since all salp colonies begin their development as a transversal double chain, we characterized each adult colonial architecture as a series of developmental transitions, such as rotations and translations of zooids, relative to their orientation at this early shared stage. We hypothesize that all adult architectures are either final or intermediate stages within three developmental pathways toward bipinnate, cluster, or helical forms. This framework will enable comparative studies on the biomechanical implications, ecological functions, evolutionary history, and engineering applications of the diversity of salp colony architectures.
Topics: Animals; Urochordata; Life Cycle Stages; Biological Ontologies
PubMed: 38820292
DOI: 10.1086/730459 -
MBio Oct 2023The classical depiction of the lifecycle is bradyzoite excystation conversion to tachyzoites, cell lysis, and immune control, followed by the reestablishment of...
The classical depiction of the lifecycle is bradyzoite excystation conversion to tachyzoites, cell lysis, and immune control, followed by the reestablishment of bradyzoites and cysts. In contrast, we show that tachyzoite growth slows independent of the host immune response at a predictable time point following excystation. Furthermore, we demonstrate a host cell-dependent pathway of continuous amplification of the cyst-forming bradyzoite population. The developmental plasticity of the excysted bradyzoites further underlines the critical role the cyst plays in the flexibility of the lifecycle of this ubiquitous parasite. This revised model of recrudescence uncovers previously unknown complexity in the clinically important bradyzoite stage of the parasite, which opens the door to further study these novel developmental features of the intermediate life cycle.
Topics: Animals; Toxoplasma; Life Cycle Stages; Protozoan Proteins
PubMed: 37675999
DOI: 10.1128/mbio.01836-23 -
MSphere Oct 2023is a developmentally regulated, obligate intracellular bacterium that encodes three sigma factors: σ66, σ54, and σ28. σ66 is the major sigma factor controlling most...
is a developmentally regulated, obligate intracellular bacterium that encodes three sigma factors: σ66, σ54, and σ28. σ66 is the major sigma factor controlling most transcription initiation during early- and mid-cycle development as the infectious elementary body (EB) transitions to the non-infectious reticulate body (RB) that replicates within an inclusion inside the cell. The roles of the minor sigma factors, σ54 and σ28, have not been well characterized to date; however, there are data to suggest each functions in late-stage development and secondary differentiation as RBs transition to EBs. As the process of secondary differentiation itself is poorly characterized, clarifying the function of these alternative sigma factors by identifying the genes regulated by them will further our understanding of chlamydial differentiation. We hypothesize that σ54 and σ28 have non-redundant and essential functions for initiating late gene transcription thus mediating secondary differentiation in . Here, we demonstrate the necessity of each minor sigma factor in successfully completing the developmental cycle. We have implemented and validated multiplexed Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) interference techniques, novel to the chlamydial field to examine the effects of knocking down each alternative sigma factor individually and simultaneously. In parallel, we also overexpressed each sigma factor. Altering transcript levels for either or both alternative sigma factors resulted in a severe defect in EB production as compared to controls. Furthermore, RNA sequencing identified differentially expressed genes during alternative sigma factor dysregulation, indicating the putative regulons of each. These data demonstrate that the levels of alternative sigma factors must be carefully regulated to facilitate chlamydial growth and differentiation. IMPORTANCE is a significant human pathogen in both developed and developing nations. Due to the organism's unique developmental cycle and intracellular niche, basic research has been slow and arduous. However, recent advances in chlamydial genetics have allowed the field to make significant progress in experimentally interrogating the basic physiology of . Broadly speaking, the driving factors of chlamydial development are poorly understood, particularly regarding how the later stages of development are regulated. Here, we employ a novel genetic tool for use in while investigating the effects of dysregulating the two alternative sigma factors in the organism that help control transcription initiation. We provide further evidence for both sigma factors' essential roles in late-stage development and their potential regulons, laying the foundation for deeper experimentation to uncover the molecular pathways involved in chlamydial differentiation.
Topics: Humans; Chlamydia trachomatis; Sigma Factor; Clustered Regularly Interspaced Short Palindromic Repeats; Regulon; Base Sequence
PubMed: 37747235
DOI: 10.1128/msphere.00391-23 -
Frontiers in Physiology 2023The dynamic nature of developing organisms and how they function presents both opportunity and challenge to researchers, with significant advances in understanding...
The dynamic nature of developing organisms and how they function presents both opportunity and challenge to researchers, with significant advances in understanding possible by adopting innovative approaches to their empirical study. The information content of the phenotype during organismal development is arguably greater than at any other life stage, incorporating change at a broad range of temporal, spatial and functional scales and is of broad relevance to a plethora of research questions. Yet, effectively measuring organismal development, and the ontogeny of physiological regulations and functions, and their responses to the environment, remains a significant challenge. "Phenomics", a global approach to the acquisition of phenotypic data at the scale of the whole organism, is uniquely suited as an approach. In this perspective, we explore the synergies between phenomics and Comparative Developmental Physiology (CDP), a discipline of increasing relevance to understanding sensitivity to drivers of global change. We then identify how organismal development itself provides an excellent model for pushing the boundaries of phenomics, given its inherent complexity, comparably smaller size, relative to adult stages, and the applicability of embryonic development to a broad suite of research questions using a diversity of species. Collection, analysis and interpretation of whole organismal phenotypic data are the largest obstacle to capitalising on phenomics for advancing our understanding of biological systems. We suggest that phenomics within the context of developing organismal form and function could provide an effective scaffold for addressing grand challenges in CDP and phenomics.
PubMed: 37645563
DOI: 10.3389/fphys.2023.1229500 -
AIMS Microbiology 2023Fire blight disease, caused by the bacterial pathogen , has been a significant concern for over 50 countries worldwide. The efficacy of chemical pesticides currently...
Fire blight disease, caused by the bacterial pathogen , has been a significant concern for over 50 countries worldwide. The efficacy of chemical pesticides currently available for disease control is limited. To address this issue, research is being conducted to explore environmentally friendly control methods, particularly biological control using beneficial microorganisms. However, there is limited research on the apple microbiota community and minimal research has been conducted on fungal communities that may exhibit reliable performance in apple trees. Therefore, our objective was to analyze the fungal communities present in apples at different developmental stages and in different tissues, aiming to identify potential biological control agents for fire blight disease. Our findings indicate that the fungal communities present in apple buds, flowers and leaves play an important role in inhibiting the invasion of . Specifically, we propose GS11 and as potential keystone taxa that respond to fire blight disease. These findings provide insights into the continuity and discontinuity of fungal community structure in different developmental stages of apples and offer predictions for potential biological control agents for fire blight disease.
PubMed: 37649796
DOI: 10.3934/microbiol.2023029 -
Psychology in Russia : State of the Art 2023Piotr Ya. Galperin and his collaborator Nina F. Talyzina performed solid experimental work which led them to propose the theory of stage-by-stage formation of mental...
BACKGROUND
Piotr Ya. Galperin and his collaborator Nina F. Talyzina performed solid experimental work which led them to propose the theory of stage-by-stage formation of mental actions and concepts, as well as a method to investigate cognitive processes, whose conceptual and procedural streamlining demands analysis and systematization.
OBJECTIVE
To investigate the formative experiment of P.Ya. Galperin and N.F. Talyzina, with the aim of analyzing their contributions to the method of psychological investigation of cognitive processes.
DESIGN
The article is part of a theoretical research project on developmental didactics systems, of which the Galperin-Talyzina system is one. Russian works by the two authors and their translations into English, Spanish, and Portuguese, as well as works by other psychologists and educators from the Galperin-Talyzina school, were sources of the work.
RESULTS
The experiments of P.Ya. Galperin and N.F. Talyzina studied, promoted, and analyzed the assimilation of new knowledge and mental actions, by introducing different conditions. The article systematizes the stages and procedures of such experiments, as well as the series and steps of diagnosis of the developmental level and the formation of mental actions and concepts, in relation to the type of Orienting Basis of an Action (OBA).
CONCLUSION
The theory was built on the basis of simultaneous production of a method to study the genesis of the cognitive processes and the theory of stage-by-stage formation of mental actions and concepts; it led us to define the method of P.Ya. Galperin and N.F. Talyzina as a gradual formation experiment.
PubMed: 38024567
DOI: 10.11621/pir.2023.0304 -
BioRxiv : the Preprint Server For... Aug 2023The typical life cycle in most animal phyla includes a larval period that bridges embryogenesis and adulthood. Despite the great diversity of larval forms, all larvae...
The typical life cycle in most animal phyla includes a larval period that bridges embryogenesis and adulthood. Despite the great diversity of larval forms, all larvae grow, acquire adult morphology and function, while navigating their habitats to obtain resources necessary for development. How larval development is coordinated with behavior remains substantially unclear. Here, we describe features of the iterative organization of larval stages that serve to assess the environment and procure resources prior to costly developmental commitments. We found that male-excreted pheromones accelerate the onset of adulthood in hermaphrodites by coordinately advancing multiple developmental events and growth during the last larval stage. The larvae are sensitive to the accelerating male pheromones only at the end of the penultimate larval stage, just before the acceleration begins. Other larval stages also contain windows of sensitivity to environmental inputs. Importantly, behaviors associated with search and consumption of food are distinct between early and late portions of larval stages. We infer that each larval stage in is subdivided into two epochs: A) global assessment of the environment to identify the most suitable patch and B) consumption of sufficient food and acquisition of salient information for developmental events in the next stage. We predict that in larvae of other species behavior is also divided into distinct epochs optimized either for assessing the habitat or obtaining the resources. Thus, a major role of larval behavior is to coordinate the orderly progression of development in variable environments.
PubMed: 37609125
DOI: 10.1101/2023.08.04.552015 -
Frontiers in Physiology 2023The predatory natural enemy plays a crucial role in agricultural ecosystems due to its effective pest control measures and defensive venom. Predator venom contains...
The predatory natural enemy plays a crucial role in agricultural ecosystems due to its effective pest control measures and defensive venom. Predator venom contains serine protease inhibitors (SPIs), which are the primary regulators of serine protease activity and play key roles in digestion, development, innate immunity, and other physiological regulatory processes. However, the regulation mechanism of SPIs in the salivary glands of predatory natural enemies is still unknown. In this study, we sequenced the transcriptome of salivary gland and identified 38 SPIs genes named . Through gene structure, multiple sequence alignment and phylogenetic tree analysis, real-time quantitative PCR (RT-PCR) expression profiles of different developmental stages and different tissues were analyzed. RNAi technology was used to explore the gene function of . The results showed that these 38 EfSPIs genes contained 8 SPI domains, which were serpin, TIL, Kunitz, Kazal, Antistasin, Pacifastin, WAP and A2M. The expression profile results showed that the expression of different types of EfSPIs genes was different at different developmental stages and different tissues. Most of the EfSPIs genes were highly expressed in the egg stage. The , and genes of the Pacifastin subfamily and the gene of the A2M subfamily were highly expressed in the nymphal and adult stages, which was consistent with the RT-qPCR verification results. These five genes are positively correlated with each other and have a synergistic effect on , and they were highly expressed in salivary glands. After interfering with the expression of the gene, the survival rate and predatory amount of male and female adults were significantly decreased. Taken together, we speculated some EfSPIs may inhibit trypsin, chymotrypsin, and elastase, and some EfSPIs may be involved in autoimmune responses. was essential for the predation and digestion of , and the functions of other EfSPIs were discussed. Our findings provide valuable insights into the diversity of EfSPIs in and the potential functions of regulating their predation, digestion and innate immunity, which may be of great significance for developing new pest control strategies.
PubMed: 37795265
DOI: 10.3389/fphys.2023.1248354 -
Neuron Mar 2024The coupling between Ca channels and release sensors is a key factor defining the signaling properties of a synapse. However, the coupling nanotopography at many...
The coupling between Ca channels and release sensors is a key factor defining the signaling properties of a synapse. However, the coupling nanotopography at many synapses remains unknown, and it is unclear how it changes during development. To address these questions, we examined coupling at the cerebellar inhibitory basket cell (BC)-Purkinje cell (PC) synapse. Biophysical analysis of transmission by paired recording and intracellular pipette perfusion revealed that the effects of exogenous Ca chelators decreased during development, despite constant reliance of release on P/Q-type Ca channels. Structural analysis by freeze-fracture replica labeling (FRL) and transmission electron microscopy (EM) indicated that presynaptic P/Q-type Ca channels formed nanoclusters throughout development, whereas docked vesicles were only clustered at later developmental stages. Modeling suggested a developmental transformation from a more random to a more clustered coupling nanotopography. Thus, presynaptic signaling developmentally approaches a point-to-point configuration, optimizing speed, reliability, and energy efficiency of synaptic transmission.
Topics: Reproducibility of Results; Synapses; Synaptic Transmission; Purkinje Cells; Presynaptic Terminals; Calcium
PubMed: 38215739
DOI: 10.1016/j.neuron.2023.12.002