東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back to Search results for [ null ]

Switch To: Labeled | MARC Mode | ISBD

The Effects of Environmental Stresso...

Kang, Manzhu.

Linked to FindBook

Google Book

Amazon

博客來

The Effects of Environmental Stressors and Stressor Interactions on the Evolutionary Dynamics of Bacterial Population and Gene Epistasis.

Record Type:	Electronic resources : Monograph/item
Title/Author:	The Effects of Environmental Stressors and Stressor Interactions on the Evolutionary Dynamics of Bacterial Population and Gene Epistasis./
Author:	Kang, Manzhu.
Published:	Ann Arbor : ProQuest Dissertations & Theses, : 2019,
Description:	140 p.
Notes:	Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
Contained By:	Dissertations Abstracts International81-05B.
Subject:	Evolution & development. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=22623849
ISBN:	9781687944597

The Effects of Environmental Stressors and Stressor Interactions on the Evolutionary Dynamics of Bacterial Population and Gene Epistasis.
Kang, Manzhu.

The Effects of Environmental Stressors and Stressor Interactions on the Evolutionary Dynamics of Bacterial Population and Gene Epistasis. - Ann Arbor : ProQuest Dissertations & Theses, 2019 - 140 p.

Source: Dissertations Abstracts International, Volume: 81-05, Section: B.

Thesis (Ph.D.)--University of California, Los Angeles, 2019.

This item must not be sold to any third party vendors.

Environmental stressors come in many different forms and affect every level of ecological organization. In a natural environment, organisms experience mixtures of stressors at various doses or strengths of exposure that could be constantly changing, both temporally and spatially. Complex environmental regimes and interactions among multiple stressors can have a profound effect on both the short-term fitness of organisms and their long-term evolutionary dynamics. This dissertation uses a bacterium-drug system to study drug-drug, drug-temperature, and gene-gene interactions. The first question we ask is how bacteria evolve to combat new stressors. Through an interaction network clustering approach followed by transcriptomic analysis, we show that Escherichia coli may have co-opted its cellular response to temperature stress for antibiotic stress because these stressors share similar physiological effects. We also found that antibiotic stress modifies the thermal response of E. coli by altering both its optimal growth temperature and temperature breadth. Next, we ask how we can identify and quantify dose-dependent drug interactions, including interactions among more than two components, i.e., higher-order interactions. To do this, we introduce a novel visual representation termed interaction landscape to directly map local dose-dependent interactions and the transitions between different interaction classes. Finally, we ask how gene-gene interactions change in fluctuating environments. We showed that changes in the type and magnitude of environmental fluctuations could affect fitness due to the differences in epistatic interactions of mutations. We quantify structural features of fitness landscapes by calculating the ruggedness across broad concentration gradients of various antibiotics. We show that fluctuating environments frequently lead to epistasis sign switches (from negative to positive or vice versa) on the pairwise level, as a potential mechanism to either promote specialization or maintain genetic variation. Overall, this dissertation combines experimental, mathematical, and computational biology to identify and understand the structures and patterns of interactions at different scales and their effects on the fitness and eco-evolutionary dynamics of bacterial populations.

ISBN: 9781687944597Subjects--Topical Terms:

3172418
Evolution & development.
Subjects--Index Terms:

Antibiotics

The Effects of Environmental Stressors and Stressor Interactions on the Evolutionary Dynamics of Bacterial Population and Gene Epistasis.
LDR:03647nmm a2200397 4500 001 2272810
005 20201105110230.5
008 220629s2019 ||||||||||||||||| ||eng d
020 $a 9781687944597
035 $a (MiAaPQ)AAI22623849
035 $a AAI22623849
040 $a MiAaPQ $c MiAaPQ
100 1 $a Kang, Manzhu. $3 3550234
245 1 4 $a The Effects of Environmental Stressors and Stressor Interactions on the Evolutionary Dynamics of Bacterial Population and Gene Epistasis.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2019
300 $a 140 p.
500 $a Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
500 $a Advisor: Yeh, Pamela J.
502 $a Thesis (Ph.D.)--University of California, Los Angeles, 2019.
506 $a This item must not be sold to any third party vendors.
506 $a This item must not be added to any third party search indexes.
520 $a Environmental stressors come in many different forms and affect every level of ecological organization. In a natural environment, organisms experience mixtures of stressors at various doses or strengths of exposure that could be constantly changing, both temporally and spatially. Complex environmental regimes and interactions among multiple stressors can have a profound effect on both the short-term fitness of organisms and their long-term evolutionary dynamics. This dissertation uses a bacterium-drug system to study drug-drug, drug-temperature, and gene-gene interactions. The first question we ask is how bacteria evolve to combat new stressors. Through an interaction network clustering approach followed by transcriptomic analysis, we show that Escherichia coli may have co-opted its cellular response to temperature stress for antibiotic stress because these stressors share similar physiological effects. We also found that antibiotic stress modifies the thermal response of E. coli by altering both its optimal growth temperature and temperature breadth. Next, we ask how we can identify and quantify dose-dependent drug interactions, including interactions among more than two components, i.e., higher-order interactions. To do this, we introduce a novel visual representation termed interaction landscape to directly map local dose-dependent interactions and the transitions between different interaction classes. Finally, we ask how gene-gene interactions change in fluctuating environments. We showed that changes in the type and magnitude of environmental fluctuations could affect fitness due to the differences in epistatic interactions of mutations. We quantify structural features of fitness landscapes by calculating the ruggedness across broad concentration gradients of various antibiotics. We show that fluctuating environments frequently lead to epistasis sign switches (from negative to positive or vice versa) on the pairwise level, as a potential mechanism to either promote specialization or maintain genetic variation. Overall, this dissertation combines experimental, mathematical, and computational biology to identify and understand the structures and patterns of interactions at different scales and their effects on the fitness and eco-evolutionary dynamics of bacterial populations.
590 $a School code: 0031.
650 4 $a Evolution & development. $3 3172418
650 4 $a Microbiology. $3 536250
650 4 $a Genetics. $3 530508
653 $a Antibiotics
653 $a Drug interactions
653 $a Epistasis
653 $a Gene interactions
653 $a Stressors
653 $a Temperature
690 $a 0412
690 $a 0410
690 $a 0369
710 2 $a University of California, Los Angeles. $b Biology 0123. $3 2049808
773 0 $t Dissertations Abstracts International $g 81-05B.
790 $a 0031
791 $a Ph.D.
792 $a 2019
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=22623849