Modulation of Cellular Signaling by Protein-Protein Interaction Inhibitor

Simple item page
dc.contributor.advisorGilbertson, Scott R.
dc.contributor.committeeMemberHoffman, David M.
dc.contributor.committeeMemberDaugulis, Olafs
dc.contributor.committeeMemberCuny, Gregory D.
dc.contributor.committeeMemberColtart, Don M.
dc.creatorYang, Taegyun 1970-
dc.date.accessioned2019-11-08T02:35:31Z
dc.date.createdAugust 2019
dc.date.issued2019-08
dc.date.submittedAugust 2019
dc.date.updated2019-11-08T02:35:33Z
dc.description.abstractSerotonin GPCR subtype 2C (5-HT2CR) plays an important role in reducing the rate of relapse in drug addiction by regulating neuronal firing in dopaminergic reward pathway. When PTEN (protein phosphatase and tensin homologue) interacts with 5-HT2CR, intracellular signaling of 5-HT2CR ceases. An eight-residue peptide (3L4F-F1) of 5-HT2CR disrupted this interaction to restore intracellular signaling of 5-HT2CR. Arginine (R)-alanine (A)-asparagine (N) sequence in the 3L4F-F1 peptide was modified into RGD- or isoDGR- sequence, which interacts with integrin in the cellular membrane for endocytosis for cellular uptake. Using an alanine scan, arginine, asparagine, and aspartic acid were determined to be important for binding with PTEN. α-helix mimic peptides containing said amino acids were synthesized and evaluated by calcium assay. Those α-helix mimic peptides showed promising inhibition activity in positive allosteric modulation (PAM) assay. PTEN is comprised of catalytic domain, C2 domain, and PTD in C-terminal. To find the binding site in the interface between PTEN and 3L4F, photoaffinity probe of diazirine was synthesized and tagged to 3L4F-F1 peptide, which will be bound to PTEN. Autophagy is a cellular degradative pathway that plays diverse roles such as homeostasis, and immune defense system. Beclin-1 in PtIns3K complex is the key protein inducing autophagy. GAPR-1 protein as negative regulator of autophagy interacts with ECD 265-284 (evolutionary conserved domain) of Beclin-1 to inhibit autophagy. The synthetic peptide of ECD 265-284 blocks the interface of the GAPR-1 and Beclin-1 to restore autophagy induction. Based on the result of the alanine scan, the L-17 peptide was composed of the key residues for inducing autophagy. We synthesized α-helix mimic cyclic L-17 peptide for better binding efficiency and α-helix mimetic small organic compound based on the aryl template. 5-HT2CR plays an important role to suppress the neuronal firing in response to drug intake. 5-HT2CR/5-HT2AR GPCR dimer is formed between TM4 and TM5. We synthesized truncated TM4 of 5-HT2CR coupled to PEG (MW=5,000) by disulfide bridge to modulate the crosstalk between 5-HT2CR and 5-HT2AR by inhibiting the dimerization of the two GPCRs. In luciferase complementary assay (LCA), the PEG-SS-TM4 showed promising inhibitory effect against the dimerization of 5-HT2CR and 5-HT2AR.
dc.description.departmentChemistry, Department of
dc.format.digitalOriginborn digital
dc.format.mimetypeapplication/pdf
dc.identifier.urihttps://hdl.handle.net/10657/5330
dc.language.isoeng
dc.rightsThe author of this work is the copyright owner. UH Libraries and the Texas Digital Library have their permission to store and provide access to this work. Further transmission, reproduction, or presentation of this work is prohibited except with permission of the author(s).
dc.subjectProtein-protein interaction inhibitor
dc.subjectPTEN
dc.subject5-HT2CR
dc.subjectAutophagy
dc.subjectCrosstalk
dc.titleModulation of Cellular Signaling by Protein-Protein Interaction Inhibitor
dc.type.dcmiText
dc.type.genreThesis
local.embargo.lift2021-08-01
local.embargo.terms2021-08-01
thesis.degree.collegeCollege of Natural Sciences and Mathematics
thesis.degree.departmentChemistry
thesis.degree.disciplineChemistry
thesis.degree.grantorUniversity of Houston
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Philosophy

Files

Original bundle

Now showing 1 - 1 of 1
Thumbnail Image
Name:
YANG-DOCTORALTHESISEDD-2019.pdf
Size:
5.27 MB
Format:
Adobe Portable Document Format
Download

License bundle

Now showing 1 - 2 of 2
No Thumbnail Available
Name:
PROQUEST_LICENSE.txt
Size:
4.43 KB
Format:
Plain Text
Description:
Download
No Thumbnail Available
Name:
LICENSE.txt
Size:
1.81 KB
Format:
Plain Text
Description:
Download

Collections

Published ETD Collection