All ETDs from UAB

Advisory Committee Chair

Shahid Mukhtar

Advisory Committee Members

Mario Izaguirre-Sierra

Karolina Mukhtar

Sorina Popescu

Stephen Watts

Document Type

Dissertation

Date of Award

2020

Degree Name by School

Doctor of Philosophy (PhD) College of Arts and Sciences

Abstract

Under normal conditions, plants devote resources for growth, development, and reproduction. These processes require finely tuned coordination between multiple physio logical pathways. In this dissertation, we explore the connectivity of these pathways as well as what happens when the plant is challenged by biotic stress such as a bacterial pathogen. We are able to use network biology approaches in conjunction with yeast two hybrid and BiFC assays to construct a network of leucine-rich repeat receptor kinases. Furthermore, we elucidated novel effector-host interactions through the aforementioned network. Lastly, we explored the role of the glyoxylate cycle, in particular peroxisomal citrate synthase (CSY2 and CSY3), in leaf senescence and plant defense. We discovered peroxisomal citrate synthase is transcriptionally up regulated during both processes. Ad ditionally, mutants lacking peroxisomal citrate synthase showed a delay in the onset of senescence and an increase in plant resistance to virulent pathogens. Lastly, we were able to identify ASR3 as a negative regulator of CSY2 and CSY3 gene expression during se nescence and biotic stress. ASR3 transcripts decreased during both processes. Overall, this work demonstrates the interaction between developmental processes and biotic stress response in plants.

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