20.500.12556/RUL-183990 The role of plectin in processes associated with focal adhesions in mouse astrocytes Vloga plektina v procesih, povezanih s fokalnimi adhezijami v mišjih astrocitih Plectin is a cytoskeletal linker protein that is highly enriched in glial cells. This thesis investigates the role of plectin in focal adhesion (FA)-associated processes in cultured mouse astrocytes. Super-resolution microscopy revealed that plectin localizes to FAs, where it exhibits a distinct structural organization and becomes progressively enriched during FA maturation. Live-cell imaging demonstrated that plectin regulates FA turnover during astrocyte spreading and influences the mobility of individual FA proteins. Consistent with the importance of FA dynamics for cell spreading and migration, plectin-deficient astrocytes exhibited reduced single-cell mobility, decreased spreading area and a rounder morphology compared with wild-type astrocytes. FA-cytoskeleton colocalization analyses revealed that loss of plectin reduces the association of FAs with the intermediate filament (IF) protein vimentin. Connectivity analysis showed that plectin deficiency disrupts the architecture of IF and microtubule networks. These alterations were accompanied by decreased cellular stiffness. Given the interaction between plectin and aquaporin 4, the role of plectin in astrocyte volume regulation was examined, revealing altered kinetics of local peripheral swelling. Astrocytes respond to pathological stimuli through reactive astrogliosis, which is characterized by cytoskeletal remodeling and upregulation of IFs. In a model of reactive astrocytes we have confirmed elevated plectin levels along with an increased number and size of FAs, suggesting the involvement of plectin in pathological conditions. Collectively, this work identifies plectin as a regulator of cytoskeletal organization, FA dynamics, cellular mechanics, and local volume regulation in astrocytes. Plektin je povezovalni protein citoskeleta, ki se v osrednjem živčnem sistemu (OŽS) posebej izrazito izraža v astrocitih. V doktorski nalogi smo preučevali vlogo plektina v procesih, povezanih s fokalnimi adhezijami (FA) v mišjih astrocitih v kulturi. Z visoko-ločljivostno mikroskopijo smo pokazali, da se plektin z značilno prostorsko organizacijo izraža v FA, kjer se postopno kopiči v bolj zrelih FA. Nadalje smo pokazali, da plektin sodeluje pri dinamiki FA med razraščanjem astrocitov in vpliva na mobilnost posameznih proteinov v FA. Skladno z vlogo FA pri razraščanju in migraciji celic, so astrociti, ki niso izražali plektina, bili manj mobilni, bolj okrogli in imeli manjšo površino v primerjavi z astrociti divjega tipa. V teh celicah smo izmerili nižjo stopnjo kolokalizacije med FA in intermediarnim filamentom (IF) vimentinom. S kvantitativno analizo povezljivosti mrež citoskeleta smo ovrednotili, kako odsotnost plektina poruši arhitekturo IF in mikrotubulov. Omenjene spremembe je spremljala nižja elastičnost astrocitov brez plektina. Plektin kolokalizira z vodnim kanalom akvaporinom 4, zato smo preučili vlogo plektina v uravnavanju volumna astrocitov in razkrili, da plektin vpliva na kinetiko lokalnega nabrekanja celic. Astrociti se na patološke dražljaje odzivajo z reaktivno astrogliozo, za katero so značilne preureditve citoskeleta in povišano izražanje IF. V modelu reaktivnih astrocitov smo izmerili povišano izražanje plektina ter večje število in velikost FA. Ugotavljamo, da plektin uravnava organizacijo citoskeleta, dinamiko FA, mehanske lastnosti in lokalno nabrekanje astrocitov ter lahko prispeva k patološkim procesom OŽS. plectin astrocytes focal adhesions intermediate filaments reactive astrogliosis plektin astrociti fokalne adhezije intermediarni filamenti reaktivna astroglioza true false false [B. Furlani] Angleški jezik Slovenski jezik Doktorsko delo/naloga 2026-06-23 13:09:00 2026-06-23 13:09:09 2026-06-24 09:05:39 0000-00-00 00:00:00 2026 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1970-01-01 572.788(043.3) 280197 282653699 57922.pdf 57922.pdf 1 1CF1A830703A4AC68B1B59C03C45423D 1dbbff76f3f2aee09428f768ddaca37875b0548737f29c7118dc495102139f0d e05e5b31-6ef3-11f1-9b0d-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=236366 Biotehniška fakulteta 0 0 0