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Roszkowska, M.

Publications and source records attributed to Roszkowska, M..

7 recordsLinked to original sources

Temporal and protein-specific S-palmitoylation supports synaptic and neural network plasticity

S-palmitoylation, a dynamic post-translational modification, has long been suggested to play a pivotal role in synaptic plasticity, learning, and memory. However, its precise impact on synaptic proteins and function remains unclear. In this study, we show that acute protein depalmitoylation in the hippocampus differentially affects short- and long-term synaptic plasticity, depending on synapse type. Strikingly, depalmitoylation also reprograms neuronal spiking timing following associative network activation. Our research identifies pre- and postsynaptic proteins dynamically regulated by S-palmitoylation during synaptic plasticity and suggests this modification occurs in isolated excitatory synapses. We also demonstrate that S-palmitoylation targets specific proteins within minutes and is not proteome-wide. These findings mark a significant advance in understanding how lipid modifications drive neural adaptability, memory, and learning.

neuroscience↗

How long can tardigrades survive in anhydrobiotic state? Searching on tardigrade anhydrobiosis patterns

Anhydrobiosis is a desiccation tolerance that denotes the ability to survive almost complete dehydration without sustaining damage. However, knowledge on the survival capacity of anhydrobiosis in various species of tardigrades is still very limited. Our research has compared anhydrobiotic capacities of four tardigrade species: Echiniscus testudo, Paramacrobiotus experimentalis, Pseudohexapodibius degenerans and Macrobiotus pseudohufelandi, which differ in feeding behaviour, habitats occupied, and which belong to different genera. Moreover, in the case of Ech. testudo two populations-from urban and natural habitats-were analysed. Clear differences in the anhydrobiotic capacity were observed among different tardigrade species. These differences appear to be determined by the habitat, but not by the nutritional behaviour of the species sharing the habitat type. Moreover, the results indicated that the longer tun state duration, the more time was necessary for the animals to return to activity.

physiology↗

The molecular fingerprint of stress resilience

Stress resilience is the ability of neuronal networks to maintain their function despite the stress exposure. Using a mouse model we here investigate stress resilience phenomenon. To assess the resilient and anhedonic behavioral phenotypes developed after the induction of chronic unpredictable stress, we quantitatively characterized the structural and functional plasticity of excitatory synapses in the hippocampus using a combination of proteomic, electrophysiological, and imaging methods. Our results indicate that stress resilience is an active and multifactorial process manifested by structural, functional, and molecular changes in synapses. We reveal that chronic stress influences palmitoylation of synaptic proteins, whose profiles differ between resilient and anhedonic animals. The changes in palmitoylation are predominantly related with the glutamate receptor signaling thus affects synaptic transmission and associated structures of dendritic spines. We show that stress resilience is associated with structural compensatory plasticity of the postsynaptic parts of synapses in CA1 subfield of the hippocampus. One Sentence SummaryCompensatory remodeling of dendritic spines at the structural and molecular levels underlies stress resilience.

neuroscience↗

Verification of Hypsibius exemplaris Gasiorek et al., 2018 (Eutardigrada; Hypsibiidae) application in anhydrobiosis research

Anhydrobiosis is considered to be an adaptation of important applicative implications because it enables resistance to the lack of water. The phenomenon is still not well understood at molecular level. Thus, a good model invertebrate species for the research is required. The best known anhydrobiotic invertebrates are tardigrades (Tardigrada), considered to be toughest animals in the world. Hypsibius. exemplaris is one of the best studied tardigrade species, with its name "exemplaris" referring to the widespread use of the species as a laboratory model for various types of research. However, available data suggest that anhydrobiotic capability of the species may be overestimated. Therefore, we determined anhydrobiosis survival by Hys. exemplaris specimens using three different anhydrobiosis protocols. We also checked ultrastructure of storage cells within formed dormant structures (tuns) that has not been studied yet for Hys. exemplaris. These cells are known to support energetic requirements of anhydrobiosis. The obtained results indicate that Hys. exemplaris appears not to be a good model species for anhydrobiosis research.

zoology↗

Serum response factor is essential for synaptic maturation in the hippocampus

Disturbances of gene expression patterns that occur during brain development can severely affect signal transmission, connectivity, and plasticity--key features that underlie memory formation and storage in neurons. Abnormalities at the molecular level can manifest as changes in the structural and functional plasticity of dendritic spines that harbor excitatory synapses. This can lead to such developmental neuropsychiatric conditions as Autism spectrum disorders, intellectual disabilities, and schizophrenia. The present study investigated the role of the major transcriptional regulator serum response factor (SRF) in synapse maturation and its impact on behavioral phenotypes. Using in vitro and in vivo models of early postnatal SRF deletion, we studied its influence on key morphological and physiological hallmarks of spine development. The elimination of SRF in developing neurons resulted in a phenotype of immature dendritic spines and impairments in excitatory transmission. Moreover, using a combination of molecular and imaging techniques, we showed that SRF-depleted neurons exhibited a lower level of specific glutamate receptor mRNAs and a decrease in their surface expression. Additionally, the early postnatal elimination of SRF in hippocampal CA1 excitatory neurons caused spine immaturity and a specific social deficit that is frequently observed in autism patients. Altogether, our data suggest that the regulation of structural and functional dendritic spine maturation begins at the stage of gene transcription, which underpins the crucial role of such transcription factors as SRF. Moreover, disturbances of the postnatal expression of SRF translate to behavioral changes in adult animals.

neuroscience↗

The tardigrade Hypsibius exemplaris as an emerging model to study the mitochondrial alternative oxidase at animal organismal level

Mitochondrial alternative oxidase (AOX) is present in mitochondria of many invertebrates. Independently of the reason concerning the enzyme occurrence in animal mitochondria, expression of AOX in human mitochondria is regarded as a potential therapeutic strategy. Till now, relevant data were obtained due to heterologous AOX expression in cells and animals without natively expressed AOX. Application of animals natively expressing AOX importantly contribute the research. Thus, we investigated Hypsibius exemplaris as a model for AOX activity analysis. We observed that H. exemplaris tolerance to the blockage of the MRC complexes was diminished in the presence of AOX inhibitor and the inhibitor-sensitive respiration enabled the tardigrade respiration under condition of the blockage. Furthermore, although detection of AOX at protein level and pronounced oxygraphic registration of its activity required the MRC complex blockage, the obtained data indicated that AOX clearly contributed animal functioning. We demonstrated that AOX activity in tardigrades, can be monitored by measurement of intact specimen whole-body respiration. Furthermore, it was also possible to monitor the impact of the MRC complex IV blockage on AOX expression and AOX inhibition in the absence of the blockage on animal functioning. Thus, H. exemplaris is applied as a whole-animal model suitable to study AOX.

molecular biology↗

Mitochondrial alternative oxidase contributes to successful tardigrade anhydrobiosis

Anhydrobiosis can be described as an adaptation to lack of water. This adaptation provides some organisms including tardigrades with a set of capabilities allowing them to survive extreme conditions that even do not exist on Earth. However, the underlying cellular mechanisms are still not explained. Available data assumes important contribution of mitochondrial proteins. Since mitochondrial alternative oxidase (AOX) described as a drought response element has recently been proposed for various invertebrates including tardigrades, we have decided to check if AOX is involved in successful anhydrobiosis of tardigrades. Milnesium inceptum was used as a model for the study. We confirmed functionality of M. inceptum AOX and estimated its activity contribution to anhydrobiosis of different duration. We observed that AOX activity was particularly important for M. inceptum revival after longer-term anhydrobiosis but did not affect rehydration stage. The results may contribute to explanation and then application of anhydrobiosis underlying mechanisms.

cell biology↗