10 A niversary of IIMCB

• Swiech L, Perycz M, Malik A, Jaworski J. Role of mTOR in
physiology and pathology of the nervous system. Biochim
Biophys Acta, 2008; 1784: 116-132
• Mioduszewska B, Jaworski J, Szklarczyk AW, Klejman
A, Kaczmarek L. Inducible cAMP early repressor (ICER)evoked
delayed neuronal death in the organotypic
hippocampal culture. J Neurosci Res, 2008; 86:61-70.
Description of Current
Research
The main scientific objective of the Laboratory of
Molecular and Cellular Neurobiology is a role of the mTOR
protein kinase in neuronal cells in physiology and pathology.
We mostly focus our research on two phenomena that are
dependent on mTOR activity and are crucial for proper
formation and functioning of the neuronal networks –
dendritic arbor and synapse formation and stabilization.
In this context, we attempt to understand the role of the
phenomenon of local protein synthesis in dendrites of
neurons – a process that was undoubtedly proven to relay
on mTOR activity. Dendrites are the main site of information
input onto neurons, and different neurons have distinctive
and characteristic dendrite branching patterns. Advances
in electrophysiology and computational modeling have
clearly shown that dendritic arbor shape is one of the crucial
factors determining how signals coming from individual
synapses are integrated. In fact, several neurodevelopmental
pathologies are characterized by abnormalities in the
dendritic tree structure including a number of mental
retardation syndromes (such as Down’s, Rett’s as well as
Fragile X syndromes) and schizophrenia. Dendritic arbor
development is a multi-step process that is controlled by
both external signals and intrinsic genetic programs (Fig.
1). Only in recent years have molecular mechanisms been
elucidated for dendritic arbor development. Among the
proteins that transduce extracellular or cell surface signals
into changes in dendritic shape are several protein kinases.
Our work demonstrated for the first time that PI3K and its
downstream kinase, Akt, regulate the complexity of dendritic
branching in neurons by protein kinase mTOR (mammalian
Fig. 1. Dendritogenesis is a process strictly controlled by the combination of an intrinsic genetic program and extracellular signals causing changes in
the cytoskeleton, macromolecule synthesis and membrane turnover. Several changes occur either globally or only locally in dendrites. Adapted from
Urbanska et al., 2008.
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