Ekspresija markera autofagije HSC70, LC3B, LAMP2A, GRP78 i mTOR kod miševa bez gena St8sia1

master's thesis

• Title (english): Expression of autophagy markers HSC70, LC3B, LAMP2A, GRP78 and mTOR in St8sia1 knockout mice
• Author: Marinela Jelinčić Korčulanin
• Mentor: Natalija Filipović (mentor)
• Mentor: Petra Korać (komentor)
• Committee member: Petra Korać (predsjednik povjerenstva)
• Committee member: Petra Peharec Štefanić (član povjerenstva)
• Committee member: Inga Urlić (član povjerenstva)
• Committee member: Maja Matulić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2024-02-27, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Gen St8sia1 kodira enzim GD3-sintazu koja katalizira nastajanje GD3, disijalogangliozida b-serije, dodatkom sijalinske kiseline na GM3, monogangliozid a-serije. GD3 sudjeluje u različitim stadijima procesa autofagije. Kolokalizira s PIP3 i BECN1 tijekom formiranja fagofora, ulazi u interakciju s LC3B u membrani autofagosoma te s LAMP1 tijekom nastajanja autolizosoma. Kod miševa bez GD3-sintaze dolazi do akumulacije gangliozida a-serije i nedostatka gangliozida b- i c-serije. Cilj ovog rada bio je utvrditi je li ekspresija HSC70, LC3B, LAMP2A, GRP78 i mTOR, proteina koji sudjeluju u procesu autofagije, promijenjena kod miševa kojima nedostaje gen St8sia1. Prerezi uški devet miševa bez gena St8sia1 i pet miševa divljeg tipa korišteni su za detekciju proteina HSC70, LC3B, LAMP2A, GRP78 i mTOR imunofluorescencijskim bojenjem. Izdvojeni su dijelovi preparata koji prikazuju epidermu te je na njima analizirana ekspresija proteina od interesa. Kod miševa bez gen St8sia1 uočena je značajno povišena ekspresija proteina HSC70, GRP78 i mTOR te smanjena ekspresija proteina LC3B. Ekspresija LAMP2A nije bila promijenjena. Ovakvi rezultati ukazuju na to da nedostatak GD3-sintaze dovodi do promjena u ekspresiji pojedinih proteina povezanih s autofagijom, najvjerojatnije zbog nedostatka gangliozida GD3 i promjene ukupnog sastava gangliozida.

Abstract (english)

GD3 synthase, enzyme that catalyses formation of GD3, disialoganglioside of b-series, by adding sialic acid resiude on GM3, monosialoganglioside of a-series, is encoded by St8sia1 gene. GD3 is involved in several stages of autophagy process. It colocalizes with PIP3-BECN1 complex during the phagophore formation, interacts with LC3B in autophagosome membrane and with LAMP1 during the autolyzosome fomation. Lack of GD3 synthase leads to accumulation of a-series gangliosides and a deficiency of b- and c-series gangliosides. The aim of this theses was to investigate the effect of St8sia1 silencing on the expression of proteins HSC70, LC3B, LAMP2A, GRP78 and mTOR which are involved in autophagy. Histological sections of ear of nine St8sia1 knockout mice and five wild-type mice were used for detection of proteins HSC70, LC3B, LAMP2A, GRP78 and mTOR by immunofluorescence staining. The epidermis parts were separated and analyzed in order to quantify the expression of the proteins of interest. Increase in the expression of proteins HSC70, GRP78 and mTOR was observed in St8sia1 knockout mice, while the expression of protein LC3B was reduced. The expression of LAMP2A was not significantly different. The results of this study suggest that deficiency of GD3 synthase leads to changes in the expression of autophagy related proteins, which is probably related to GD3 deficiency and alterations of ganglioside composition.

• Keywords: gangliozid; GD3; GD3-sintaza; St8sia1; autofagija
• Keywords (english): ganglioside; GD3; GD3 synthase; St8sia1; autophagy
• Language: croatian
• URN:NBN: urn:nbn:hr:217:142513
• Study programme: Title: Molecular Biology-University graduate programme; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra molekularne biologije (sveučilišni/a magistar/magistra molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2026-02-27
• Created on: 2024-03-08 12:17:21