Wyniki wyszukiwania - Biblioteka Nauki

1

CD44 adhesion molecule interacts with vesicular transport regulators in neurons

100%

Skupien A. , Zareba-Koziol M. , Dzwonek J.

|

nr Suppl.1

EN

INTRODUCTION: The role of extracellular matrix and its cellular receptors in acquisition of proper dendrite morphology in neurons has remained enigmatic. Previously we have shown that CD44 adhesion molecule, the main hyaluronan receptor, plays a crucial inhibitory role in dendritic tree arborization. Additionally, our results clearly demonstrate that CD44 defines the structure of Golgi apparatus, suggesting that CD44 may regulate dendritic arbor development by modulating the Golgi apparatus morphology and positioning AIM(S): The aim of our work is to find molecular partners of CD44 in neurons. METHOD(S): Immunoprecipitation and subsequent mass spectrometry analysis were used to unravel new CD44-interacting proteins in cortical neurons cultured in vitro. Obtained results were validated by Western Blot analysis. RESULTS: Mass spectrometry analysis pointed out several potential CD44-interacting partners in neurons. In the group of identified proteins we have distinguished many molecules involved in cellular vesicles transport. One of them is ERC2, the protein that belongs to Rab3-interacting molecule (RIM)‑binding protein family. We confirmed the results obtained by mass spectrometry by immunoprecipitation and Western Blot methods. ERC2 protein was co-immunoprecipitated with anti-CD44 antibody, but not with the IgG control antibody. CONCLUSIONS: We have shown for the first time, that CD44 interacts with ERC2 in neurons. These results suggest that the cellular mechanism underlying CD44-dependent modulation of dendritic tree development involves the regulation of cellular vesicular transport in neuronal cells. FINANCIAL SUPPORT: 2014/15/N/NZ4/01912.

2

The role of adhesion protein CD44 in the shape changes of astrocytes

88%

Konopka A. , Swiech L. , Jaworski J. , Wilczynski G. M. , Dzwonek J.

|

nr Suppl.1

EN

CD44 is a widely distributed type I transmembrane glycoprotein and functions as the major hyaluronan receptor on most cell types. CD44 through interaction with actin cytoskeleton affects the transmission of signals from the outside to the inside of the cell in many tissues and organs. Primary cultures of astrocyte are diverse in their morphology and many factors can influence on it. In vivo astrocyte also are able to change their shape in response to various stimuli. The appearance of reactive astrocytes in vivo with thicker and longer processes and increased cellular content of glial fibrillary acidic protein (GFAP) has been observed in the CNS after various types of injury caused by physical, chemical, and pathological trauma. Furthermore, it has been showed that CD44 expression increases after brain injury. In our study we investigated the influence of knock down of CD44 by specific shRNA and CD44 overexpression on the astrocytes shape changes. Our results indicate that knock down of CD44 in astrocytes results in more regular and flat shape. In contrast the overexpression of CD44 promotes more irregular, radial-like shape of astrocyte. Our data support the hypothesis that CD44 plays role in morphological changes of astrocyte and give the opportunity to investigate its role in pathological processes such as brain injury.

3

Expression and function of extracellular matrix metalloproteinase-9 in human epilepsy

63%

Konopka A. , Grajkowska W. , Ziemianska K. , Roszkowski M. , Rysz A. , Koperski L. , Kaczmarek L. , Wilczynski G. , Dzwonek J.

|

nr S

EN

Focal cortical dysplasia (FCD) is a developmental brain disorder characterized by abnormalities of cytoarchitecture and neuronal morphology. FCD is associated with pharmacologically intractable forms of epilepsy in both children and adults. The mechanisms that underlie FCD-associated seizures are unclear. It is believed that a pathological plasticity, including abnormality of synaptic connections, plays the crucial role in this disease. Recent studies indicate the role of interactions between nerve cells and the extracellular matrix in the processes of plasticity. Matrix metalloproteinases are enzymes, which are able to degrade the extracellular matrix components, so they can play an important role in these interactions. Results of experiments using rodent models showed that extracellular matrix metalloproteinase-9 (MMP-9) can play an important role in epileptogenesis. There is no data demonstrating that MMP-9 is involved in the development of epilepsy in human. The aim of this study was to determine whether MMP-9 might play a role in FCD - related epilepsy. Expression of MMP-9 was investigated in human brain tissue derived from people suffering from epilepsy. The immunohistochemistry and antibody microarray methods were used. The control group consisted of the autopsy brain samples. The results indicate that the expression of MMP-9 in the human brain tissue with FCD is increased. The highest immunoreactivity occurs in cytoplasm of abnormal neurons. Moreover, among the 7 tested matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-10, MMP-13), MMP-9 is present in greatest concentration in the FCD tissue homogenates. The results support the hypothesis of the possible role of MMP-9 in the development of human epilepsy and give an opportunity to develop new treatments.

4

Udzial regulacji ekspresji genow w procesach integracji informacji w komorkach nerwowych.

45%

Kaczmarek L. , Kaminska-Kaczmarek B. , Savonenko A. , Lukasiuk K. , Jaworski J. , Biedermann I. , Zielinski K. , Werka T. , Nikolaev E. , Szklarczyk A. , Dzwonek J. , Kowalczyk A. , Konopka D. , Nowicka D. , Rydz M. , Filipkowski R. , Figiel-Ozog I.

|

tom 09

46-48