ProQuest
Abstract/Details

Circadian Control of a Time-Dependent Damage Response in Drosophila melanogaster

Haddad, Shahd.   University of Windsor (Canada) ProQuest Dissertation & Theses,  2023. 30528778.

Abstract (summary)

Circadian rhythms are physiological and behavioural processes that cycle in a 24-hour period, and they are driven by the circadian clock. The circadian clock is an internal molecular timekeeper that consists of a transcription-translation feedback loop, which controls the expression of many different genes, including ones involved in fasting-feeding and sleep-wake cycles, in a circadian rhythmic manner. The Drosophila intestinal epithelium is constantly renewed by intestinal stem cells (ISCs) and, during regeneration, Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) signalling drives increased ISC division and differentiation. Our lab has previously shown that regeneration is gated by the circadian clock. I therefore hypothesised that the time of intestinal damage affects the regeneration response and used a dGFP reporter of JAK/STAT activity as a readout. Two acute damage assays that allow the control of damage timing were developed: chemical feeding and genetically-induced apoptosis of epithelial cells. In both of these assays, JAK/STAT activation in response to damage is reduced in period mutants (per01). In addition, my thesis shows that the JAK/STAT activity exhibits a time-dependent rhythm in response to apoptosis, and that this rhythm is absent in per01 mutants. My research further shows that the JAK/STAT components are expressed at significantly higher levels in wildtype compared to per01 suggesting a per-dependent transcriptional mechanism regulating JAK/STAT signalling. Overall, my research shows that the JAK/STAT pathway in the midgut is regulated by the circadian clock during regeneration.

Indexing (details)


Subject
Biology;
Molecular biology;
Cellular biology;
Biochemistry
Classification
0306: Biology
0307: Molecular biology
0379: Cellular biology
0487: Biochemistry
Identifier / keyword
Apoptosis; Cell division; Circadian clock; Intestine; Regeneration; Stem cells
Title
Circadian Control of a Time-Dependent Damage Response in Drosophila melanogaster
Author
Haddad, Shahd
Number of pages
86
Publication year
2023
Degree date
2023
School code
0115
Source
MAI 84/12(E), Masters Abstracts International
ISBN
9798379775193
Advisor
Karpowicz, P.
Committee member
Vacratsis, O.; Swan, A.; Rahim, M.
University/institution
University of Windsor (Canada)
Department
BIOLOGICAL SCIENCES
University location
Canada -- Ontario, CA
Degree
M.Sc.
Source type
Dissertation or Thesis
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
30528778
ProQuest document ID
2832962239
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
https://www.proquest.com/pqdtglobal/docview/2832962239