Priprema, biokemijska i biofizička karakterizacija dviju prolinskih mutiranih varijanti ljudske dipeptidil-peptidaze III

master's thesis

• Title (english): Preparation, biochemical and biophysical characterizaion of two proline mutant variants of human dipeptidyl peptidase III
• Author: Fran Miočić-Stošić
• Mentor: Mihaela Matovina (mentor)
• Committee member: Aleksandra Maršavelski (predsjednik povjerenstva)
• Committee member: Ines Primožič (član povjerenstva)
• Committee member: Branimir Bertoša (član povjerenstva)
• Committee member: Ivan Kodrin (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2022-07-15, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Dipeptidil-peptidaza III (DPP III) sudjeluje u sustavu razgradnje proteina u stanici, a
vjerojatno i u regulaciji krvnog tlaka i boli. DPP III je također uključena u regulaciju
signalnog puta Nrf2-Keap1 putem interakcije s proteinom Keap1. Vezanje DPP III na Keap1
onemogućava razgradnju transkripcijskog faktora Nrf2 i povećava njegovu razinu u stanici,
što kod tumorskih stanica može povećati otpornost na kemoterapeutike. U bazi za genomiku
raka cBioPortal odabrane su mutirane varijante DPP III, P358L i P360S, te je istražen utjecaj
mutacija na peptidaznu aktivnost DPP III i interakciju s Keap1. Utvrđeno je da obje mutacije
smanjuju konstantu specifičnosti DPP III te da mutacija P358L povećava afinitet DPP III za
Keap1. Simulacije molekulske dinamike pokazale su da je petlja preko koje se DPP III veže
na Keap1 fleksibilnija u mutantu P358L, što je vjerojatno uzrok većeg afiniteta za Keap1.
Daljnjim istraživanjima će se pokušati utvrditi utjecaj mutacije P358L na biološku ulogu DPP
III.

Abstract (english)

Dipeptidyl peptidase III (DPP III) participates in the protein turnover, and probably in the
regulation of blood pressure and pain. It is also involved in the regulation of Keap1-Nrf2
signaling pathway through interaction with Keap1. Binding of DPP III to Keap1 hinders the
degradation of transcription factor Nrf2, and increases its cellular levels, which can cause the
resistance of cancer cells to chemotherapeutics. Two mutated variants of DPP III, P358L and
P360S were selected from cBioPortal for cancer genomics and the influence of these
mutations on DPP III peptidase activity and interaction with Keap1 were investigated. It was
found that both mutations lower the specificity constant of DPP III, while P358L mutation
increases its affinity for Keap1. Molecular dynamic simulations showed that the loop through
which DPP III binds Keap1 is more flexible in P358L mutant, which is a likely cause of the
higher affinity for Keap1. Further investigations will try to elucidate the effect of P358L
mutation on the biological role of DPP III.

• Keywords: AMBER; dipeptidil-peptidaza III; izotermalna kalorimetrija; kinetika; mutageneza; molekulska dinamika; proteinske interakcije
• Keywords (english): AMBER; dipeptidyl peptidase III; isothermal calorimetry; kinetics; mutagenesis; molecular dinamics; protein interaction
• Language: croatian
• URN:NBN: urn:nbn:hr:217:918165
• Project: Number: IP-2020-02-6743; Title: Interakcija dipeptidil peptidaze III s proteinom SH2 domain-containing protein 3C – moguća veza između odgovora na oksidativni stres i stanične migracije; Title: Dipeptidyl peptidase III interaction with SH2 domain-containing protein 3C – possible link between oxidative stress response and cell migration; Acronym: OxMiLink; Leader: Mihaela Matovina; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2023-07-15
• Created on: 2022-09-29 16:43:15