O prenosu vzročnih variant za poligenske lastnosti kvasovke

magistrsko delo

Gašper Žun (Author), Uroš Petrovič (Mentor), Marina Klemenčič (Thesis defence commission member), Marko Dolinar (Thesis defence commission member)

Abstract

Genetska arhitektura poligenskih lastnosti je kompleksna. Vsi vzročni elementi v splošnem niso poznani, k variabilnosti take lastnosti pa prispevajo tudi viri dedljivosti višjih redov. Da bi odkrili in ovrednotili vzročne variante za variabilnost v odpornosti kvasovke Saccharomyces cerevisiae proti NaCl kot poligenski lastnosti, smo križali haploidna starševska seva različnih fenotipov. Spremljali smo porazdelitev fenotipa v populaciji njunih potomcev (segregant) in spreminjanje povprečnega fenotipa populacije v sedmih stopnjah povratnega križanja. Po koraku fenotipizacije vsake generacije smo odbrali segreganto z najbolj izboljšanim fenotipom. Na osnovi analize porazdelitve frekvenc starševskih alelov v povprečni populaciji in populaciji, sposobni rasti v ekstremno slanih pogojih, smo predpostavili potencialne vzročne lokuse kvantitativne lastnosti (QTL). Njihov prenos skozi generacije povratnega križanja smo spremljali na osnovi genomskih zaporedij proti soli najbolj odpornih segregant. S primerjavo prenosa potencialnih lokusov kvantitativne lastnosti, spreminjanjem povprečnega fenotipa populacije in določenega fenotipa najbolj odpornih segregant, smo ovrednotili vzročnost lokusov kvantitativne lastnosti. Da bi vzročne elemente določili natančneje, smo jih skušali opredeliti na mehanistični molekularnobiološki ravni. Glede na heterogenost in funkcijsko vključenost genov znotraj lokusa kvantitativne lastnosti smo predlagali nove vzročne gene kvantitativne lastnosti (QTG). Razliko v fenotipu smo pojasnili na osnovi napovedi strukturnih variant produktov mogočih vzročnih genov kvantitativne lastnosti. Predpostavili smo potencialne razlike v vlogi in delovanju proteinskih variant, ki vodijo v variabilnost odpornosti proti NaCl.

Keywords

kvasovke;Saccharomyces cerevisiae;poligenske lastnosti;vzorčne variante;lokus kvantitativne lastnosti;ekstremno kartiranje QTL;analiza X-QTL;magistrska dela;

Data

Language:	Slovenian
Year of publishing:	2020
Typology:	2.09 - Master's Thesis
Organization:	UL FKKT - Faculty of Chemistry and Chemical Technology
Publisher:	[G. Žun]
UDC:	577.21:582.282.23(043.2)
COBISS:	32630019
Views:	488
Downloads:	168
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	On the inheritance of causative variants for polygenic traits in yeast
Secondary abstract:	Polygenic trait’s genetic architecture is complex and all its causative elements are generally unknown. Variability of such a trait also depends on higher order heritability factors. To dissect and assess causative variants for NaCl tolerance as a case of a polygenic trait, we crossed 2 parental haploid yeast strains of large phenotypic difference. We monitored the distribution of the phenotype in a population of their progeny and following 7 generations of backcrossing. After each phenotyping step of a given generation, we selected the offspring strain with the most advanced phenotype. Analysis of distribution of parental alleles in populations growing in extreme saline and reference conditions allowed us to predict possible causative quantitative trait loci (QTL). On the basis of genomic sequences of the selected segregants we followed the inheritance of predicted quantitative trait loci over the generations. Inheritance of potential quantitative trait loci, average population phenotype shift and quantitatively assessed phenotype of selected segregants pointed out importance of certain quantitative trait loci. To determine causative elements more toroughly, we provided their relatedness on mechanistic and molecular biology level. Our prediction of novel quantitative trait genes (QTG) is based on heterogeneity and functional relatedness of genes within notable quantitative trait loci. Phenotypic diversity was justified on the basis of predicted structural variants of products of possible causative quantitative trait genes. We presumed potential differences in both role and mechanism of action of protein variants that lead to variability in resistance to NaCl.
Secondary keywords:	yeast;polygenic traits;causative variants;quantitative trait locus;X-QTL analysis;
Type (COBISS):	Master's thesis/paper
Study programme:	1000377
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. v Ljubljani, Fak. za kemijo in kemijsko tehnologijo, smer Biokemija
Pages:	148 str.
ID:	12033193