Molekularni učinci proteina alfa sinukleina u jezgri: vezanje na molekulu DNA i regulacija transkripcije

doctoral thesis

• Title (english): Molecular effects of protein alpha synuclein in the nucleus: DNA binding and transcriptional regulation
• Author: Kristina Gotovac
• Mentor: Fran Borovečki (mentor); MBZ: 230266
• Committee member: Vlatka Zoldoš (član povjerenstva)
• Committee member: Sanja Kapitanović (član povjerenstva)
• Committee member: Nevenka Meštrović Radan (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2014, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology
• Universal decimal classification (UDC): 577 - Biochemistry. Molecular biology. Biophysics

Abstract

Protein alfa sinuklein uključen je u vezikularni transport u sinapsama neurona i regulaciju otpuštanja dopamina, te se smatra da igra važnu ulogu u nastanku Parkinsonove bolesti (PB). Točan mehanizam kojim ovaj protein utječe na oštećenje dopaminergičkih neurona, glavnog patološkog obilježja PB, još uvijek je nepoznat. Budući da je alfa sinuklein lokaliziran u jezgri neurona, te je pokazano da se vezuje za DNA, jedan od mogućih mehanizama jest deregulacija transkripcije. Glavni cilj predloženog istraživanja bio je istražiti učinak alfa sinukleina u jezgri, kao i moguće mehanizme deregulacije transkripcije na razini cijelog genoma u modelima PB. Analiza genske ontologije i signalnih putova pokazala je da su geni regrutirani od strane endogenog alfa sinukleina uključeni u organizaciju i funkcioniranje sinapse, kao i razvoj središnjeg živčanog sustava, te ubikvitinsko-proteasomski sustav. U stanicama koje eksprimiraju povećane količine alfa sinukleina od regrutiranih gena najviše su bili zastupljeni oni vezani uz regulaciju transkripcije, dok su u stanicama transfeciranim s mutiranim oblikom alfa sinukleina (A53T) regrutirani geni bili povezani s regulacijom apoptoze, ali i putovima uključenim u nastanak genetskih i neuroloških bolesti. Eksperimenti su pokazali značajan utjecaj endogenog i mutiranog alfa sinukleina na promotore gena NEDD4 (ubikvitin-ligaza), SLC4A5 (natrij bikarbonat kotransporter), NRXN3 (receptor i adhezijska molekula), ADRA1A (simpatički receptor) i MAP4K4 (mitogen aktivirana protein kinaza). Rezultati dobiveni provedenim istraživanjima ukazuju na potencijalni učinak alfa-sinukleina u jezgri, prije svega kroz utjecaj na mehanizme transkripcije, što u konačnici može doprinijeti razvoju PB.

Abstract (english)

Protein alpha synuclein is involved in vesicular transport on synapses and regulation of dopamine release. There is the evidence that alpha-synuclein may play an important role in in Parkinson`s disease (PD) development but the mechanism by which alpha synuclein damages dopaminergic neurons remains elusive. As alpha synuclein is located in the nucleus of neurons and it has been shown that it binds DNA, one of the possible mechanisms is transcriptional dysregulation. The aim of the project was to investigate possible effects of alpha-synuclein in the nucleus as well as possible mechanisms of transcriptional deregulation in PD models. Gene ontology analysis and pathways analysis showed that genes recruited by endogenous alpha synuclein are mostly involved in synapse functioning and organization, development of central nervous system and ubiquitin proteasome system. In cells overexpressing alpha synuclein most of the genes were related to nucleus and transcriptional regulation, while in cells transfected with mutated alpha synuclein (A53T) recruited genes were mostly involved in apoptosis regulation and pathways involved in development of genetic and neurologic diseases. Experiments showed significant influence of endogenous and mutated alpha synuclein on promoters of genes NEDD4 (ubiquitin-ligase), SLC4A5 (sodium bicarbonate cotransporter), NRXN3 (receptor and cell adhesion molecule), ADRA1A (adrenergic receptor) and MAP4K4 (mitogen activated protein kinase). Overall results show potential effect of alpha synuclein in the nucleus, primarily through effect on transcriptional mechanisms that can finally lead to Parkinson`s disease development.

• Keywords: alfa sinuklein; regulacija transkripcije; Parkinsonova bolest; kromatinska imunoprecipitacija; genska ontologija
• Keywords (english): alpha synuclein; transcriptional regulation; Parkinson`s disease; chromatin immunoprecipitation; gene ontology
• Language: croatian
• URN:NBN: urn:nbn:hr:217:426794
• Study programme: Title: Biology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje biologija (doktor/doktorica znanosti, područje prirodnih znanosti, polje biologija)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2017-05-17 12:57:02