Szanowni Państwo,

Serdecznie zapraszamy na Seminarium Doktorantów, które odbędzie się 25 września 2026 r. o godz. 10.30 w Sali Konorskiego (II piętro). W programie przewidziane są 2 prezentacje.
Informacje dotyczące prelegentów wraz z abstraktami znajdują się poniżej.

Z pozdrowieniami,
Anna Filipek & Anna Nowicka

1. MSc: Agata Pytyś

Supervisor: Dr. Tomasz Wójtowicz, PhD, DSc.
Laboratory of Molecular Basis of Behavior, Nencki Institute of Experimental Biology, PAS

Title:  The role of protein S-palmitoylation in neuronal plasticity, learning and memory

Abstract:

S-palmitoylation is the reversible attachment of a fatty acid to cysteine residues of a protein, and it is the only lipid modification known to be reversible. This reversibility allows it to act as a dynamic switch controlling protein trafficking, membrane anchoring and thus protein’s local availability at the synapse, which makes it a plausible molecular contributor to synaptic plasticity. Despite growing interest in this modification, the extent to which the synaptic S-palmitoylome responds to neuronal activity, and how such responses relate to learning, remains incompletely understood.

Presented work examines the molecular patterns of S-palmitoylation of synaptic proteins following the induction of synaptic plasticity and following behavioral training. Four complementary experimental models were used: primary hippocampal neuronal cultures, acute hippocampal slices, isolated synaptoneurosomes, and hippocampi from rats subjected to spatial learning in the Morris water maze. In these models, plasticity-inducing stimulation did not alter the overall level of protein S-palmitoylation, but produced changes affecting a defined subset of synaptic proteins. These changes were bidirectional and protein-specific, and their direction depended on the experimental model and on the time elapsed after stimulation. The results indicate that S-palmitoylation is locally and selectively regulated at the synapse in response to neuronal activity, and support its role as a component of the molecular machinery underlying synaptic plasticity.

2. MSc: Ludwika Kondrakiewicz

Supervisor: Prof. Ewelina Knapska, PhD, DSc.
Laboratory of Emotions' Neurobiology, Nencki Institute of Experimental Biology, PAS

Title: Population-Level Representation of Social Hierarchy in the Medial Prefrontal Cortex

Abstract:

Social hierarchies shape access to resources, social interactions, and behavior in group-living species. The medial prefrontal cortex (mPFC) is implicated in dominance relationships and social behavior and represents complex sensory information, including odors. Whether the mPFC spontaneously represents social hierarchy from olfactory cues, however, remains unknown. Here, we investigated whether mPFC activity encodes social rank during passive presentation of social odors in the absence of behavioral tasks or direct interaction.

Social hierarchies were established in large groups of mice under semi-naturalistic conditions using priority of access to a limited, highly valued resource. Odors collected from individually ranked mice were presented to head-fixed mice while sniffing and neural activity were recorded. Mice exhibited stronger sniffing responses to odors from higher-ranking individuals, with responses decreasing linearly with donor rank. This effect was not explained by differences in sucrose consumption.

High-density electrophysiological recordings revealed robust mPFC responses to social odors, with stronger population responses to odors from dominant individuals. Although individual neurons lacked clear monotonic rank tuning, donor rank was linearly represented at the population level. Rank information remained decodable after accounting for sniffing-related activity. These findings demonstrate that mice spontaneously extract social hierarchy information from familiar conspecific odors and represent it through distributed mPFC population activity.