Ekspresija gena za biljnu seril-tRNA-sintetazu u uvjetima stresa

master's thesis

• Title (english): Expression of the plant-seryl-tRNA synthetase gene under stress conditions
• Author: Jurica Baranašić
• Mentor: Jasmina Rokov Plavec (mentor)
• Committee member: Jasmina Rokov Plavec (predsjednik povjerenstva)
• Committee member: Iva Juranović Cindrić (član povjerenstva)
• Committee member: Biserka Prugovečki (član povjerenstva)
• Committee member: Marko Močibob (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2017-02-09, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Seril-tRNA-sintetaza (SerRS) kao i ostale aminoacil-tRNA-sintetaze (aaRS) kovalentno povezuje aminokiselinu s odgovarajućom tRNA. Uz kanonsku ulogu u biosintezi proteina uočene su i neke nekanonske uloge aaRS, kao npr. sudjelovanje u staničnom odgovoru na stres. Prethodno je uočeno da transgenične biljke Arabidopsis thaliana koje prekomjerno eksprimiraju SerRS bolje kliju i brže rastu u odnosu na divlji tip biljke nakon izlaganja stresu. Također je pokazano kako SerRS stupa u interakciju s proteinom BEN1 koji sudjeluje u metabolizmu biljnih hormona brasinosteroida, koji sudjeluju u staničnom odgovoru na stres. U svrhu bolje karakterizacije interakcije SerRS i BEN1 te njihove potencijalne uloge u staničnom odgovoru na stres, analizirane su transgenične biljke koje prekomjerno eksprimiraju SerRS u obliku fuzijskih proteina. RT-qPCR-om, western-hibridizacijom, fluorescencijskom mikroskopijom i analizom enzimske aktivnosti pokazano je kako sve ispitane transgenične linije prekomjerno eksprimiraju kinetički aktivne fuzijske SerRS proteine. Fenotipskom analizom nije uočena razlika između transgeničnih biljaka i biljaka divljeg tipa. Prekomjerna ekspresija SerRS ne utječe na ekspresiju gena za BEN1 protein. Ispitana je ekspresija gena za SerRS pri četiri uvjeta abiotičkog stresa izazvanog povećanom koncentracijom kadmijevih iona, te je pokazano kako u većini uvjeta dolazi do povećanja ekspresije gena za SerRS. Podaci upućuju na aktivno sudjelovanje SerRS u staničnim odgovorima na abiotički stres.

Abstract (english)

Seryl-tRNA-synthetase (SerRS) just like all aminoacyl-tRNA synthetase covalently bonds amino acid with the cognate tRNA. Besides their main function in protein biosynthesis, aaRSa also developed some non-canonical functions such as participation in cellular responses to stress. Previously, it was shown that the transgenic Arabidopsis thaliana plants, that overexpress SerRS, sprout better and grow faster than wild type plants after the exposure to stress conditions. It was also shown that SerRS interacts with BEN1, a protein that is probably involved in cellular responses to stress. To better characterize the interaction between SerRS and BEN1 and their role in cell response to stress, transgenic lines that contain SerRS fusion constructs were investigated. RT-qPCR, western blot, enzyme activity analysis and fluorescent microscopy show that all transgenic lines overexpress kinetically active SerRS-fusion proteins. Phenotypic analysis didnt show any difference between transgenic plants and wild type plants. Overexpression of SerRS gene doesnt affect the expression of gene coding for BEN1. The expression of SerRS gene was monitored under four different conditions of abiotic stress, caused by high cadmium concentrations. The results show that under most conditions the expression of SerRS gene is enhanced, which indicates that SerRS is actively involved in cellular responses to abiotic stress.

• Keywords: seril-tRNA-sintetaza; abiotički stres; Arabidopsis thaliana; transgenične biljke; polimerazna lančana reakcija
• Keywords (english): seryl-tRNA synthetase; transgenic plants; Arabidopsis thaliana; abiotic stress; polymerase chain reaction
• Language: croatian
• URN:NBN: urn:nbn:hr:217:745477
• 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
• Created on: 2017-02-20 10:52:39