Multigenska analiza patosustava fitoplazme ribosomske skupine 16SrXII-A

master's thesis

• Title (english): Multigene analysis of phytoplasma 16SrXII-A pathosystem
• Author: Kasia Šturlan
• Mentor: Martina Šeruga Musić (mentor)
• Committee member: Inga Marijanović (predsjednik povjerenstva)
• Committee member: Damjan Franjević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2020, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Fitoplazme (rod 'Ca. Phytoplasma') su kozmopolitni obligatorni paraziti bez stanične stijenke koji tvore monofiletsku bakterijsku skupinu unutar razreda Mollicutes. Istraživanje fitoplazmi otežano je nemogućnošću uzgoja u kulturi in vitro. Imaju vrlo kompleksan životni ciklus koji može uključivati više biljaka-domaćina i kukaca-vektora, a uzrokuju mnoge ekonomski značajne bolesti poljoprivrednih kultura u cijelom svijetu. U Europi su jako raširene žutice vinove loze koje uzrokuju fitoplazme flavescence dorée (FD) i bois noir (BN; Ca. 'Phytoplasma solani'). Cilj ovog diplomskog rada bila je multigenska tipizacija izolata fitoplazme analizom 16S rRNA gena te gena tufB (elongacijski faktor Tu), vmp1 (varijabilni membranski protein), secY (dio sekretornog sustava translokaze) i stamp, za koje postoji indikacija da bi mogli biti važni kod razlikovanja epidemioloških karakteristika različitih sojeva. U analizu su uključeni uzorci kukaca-vektora vrste Hyalestes obsoletus, simptomatični uzorci Vitis vinifera te asimptomatični uzorci Convolvulus arvensis. Analizirani su fragmenti gena za 16S rRNA, tufB, secY, vmp1 i stamp za koje se smatra da su važni kod utvrđivanja epidemiološkog potencijala različitih fitoplazmatskih sojeva. Fragmenti su umnoženi lančanom reakcijom polimerazom, ispitani RFLP analizom te sekvencirani i obrađeni filogenetskom analizom. Pokazano je da je tufB konzerviraniji od membranskih proteina. Svi geni su se pokazali kao dobri markeri za razlučivanje sojeva i bolje razumijevanje epidemiologije fitoplazmoza.

Abstract (english)

Phytoplasmas (genus 'Ca. Phytoplasma') are obligatory intracellular wall-less cosmopolit parasites which belong to the class Mollicutes, within which they create monofiletic group. Investigations of phytoplasmas are hindered by the inability to cultivate them in a pure culture in vitro. Phytoplasmas cause great economic losses in the agriculture worldwide. Control of the diseases is difficult because of their diverse range of host and vector systems and complex life styles. Throughout European vineyards grapevine yellow diseases (GY) are caused by two types of phytoplasmas: Flavescence dorée (FD) and bois noir (BN; Ca. 'Phytoplasma solani'). The aim of this study was to perform multilocus sequence typing of phytoplasma strains isolated form vector insects Hyalestes obsoletus, symptomatic Vitus vinifera and asymptomatic weed Convolvulus arvensis. Analysis included 16Sr RNA gene and four non-ribosomal genes: tufB, vmp1, secY and stamp, for which it was shown previously that they are relevant for distinguishing epidemiological capacity of different phytoplasma straines. Fragments of these genes were amplified by PCR, analyzed by RFLP, and sequenced. Obtained sequences were aligned and phylogenetic analysis was performed. It was shown that gene tufB is more conserved then membrane proteins as expected, considering their assumed role in the phytoplasma life-cycle. All of the genes proved to be important distiguishable markers for better understanding of phytoplasma epidemiology.

• Keywords: žutice vinove loze; BN fitoplazma; MLST
• Keywords (english): grapevine yellows; BN phytoplasma; MLST; tufB; secY; vmp; stamp
• Language: croatian
• URN:NBN: urn:nbn:hr:217:611510
• Study programme: Title: Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra edukacije biologije (magistar/magistra edukacije biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-06-09 11:28:03