Characterization of KPAP, a Novel Pokeweed Antiviral Protein Isoform

Simple item page
dc.contributor.advisorHudak, Katalin A.
dc.contributor.authorDe La Selle, Fernand Jean
dc.date.accessioned2022-12-14T16:39:54Z
dc.date.available2022-12-14T16:39:54Z
dc.date.copyright2022-09-07
dc.date.issued2022-12-14
dc.date.updated2022-12-14T16:39:54Z
dc.degree.disciplineBiology
dc.degree.levelMaster's
dc.degree.nameMSc - Master of Science
dc.description.abstractPhytolacca americana is a perennial plant that harbors the pokeweed antiviral protein (PAP) genes which belong to the N-glycosidase family. These proteins are called ribosome inactivating proteins (RIPs) which remove an adenine base from the sarcin/ricin loop (SRL) of the 28S rRNA in eukaryotes. This depurination results in protein translation inhibition leading to a concentration-dependent cytotoxic consequence. Many RIPs in the plant kingdom are being discovered with new genomic sequencing technologies but, many of them remain uncharacterized. Recently, our lab discovered a new RIP called Novel PAP/KPAP in the sequenced pokeweed genome. KPAP transcript levels did not behave the same way as other isoforms under phytohormone stimulated biotic stress, however, they showed a slight decrease in drought. In this study, I provide preliminary groundwork on the KPAP gene model, expression in abiotic stresses, protein structure, depurination activity and potential binding arrangement on the SRL. My results show the presence of predicted upstream open reading frames (uORFs) in the long leader intron, perhaps belonging to retrotransposons. The enzymatic activity recorded from KPAP in an in vitro translation assay resembles the activity of PAP-I. Moreover, the exclusive expression of KPAP in leaves compared to other isoforms and its downregulation in drought may indicate a function related to photosynthesis, carbon metabolism, plant growth or leaf expansion. Structurally the predicted protein was docked in silico to an adenine base and showed a similar disposition of the active site compared to PAP-I. Lastly, KPAP was docked in silico to the E.coli SRL and residue interactions are discussed in the context of other RIPs. This early research shows KPAP’s similarities and differences compared to the other isoforms, however, much remains to be learned from this isoform and RIPs in general.
dc.identifier.urihttp://hdl.handle.net/10315/40757
dc.languageen
dc.rightsAuthor owns copyright, except where explicitly noted. Please contact the author directly with licensing requests.
dc.subjectMolecular biology
dc.subjectBiochemistry
dc.subjectPlant biology
dc.subject.keywordsPokeweed antiviral protein
dc.subject.keywordsNovel pokeweed antiviral protein
dc.subject.keywordsRibosome inactivating protein
dc.subject.keywordsin vitro translation
dc.subject.keywordsAniline assay
dc.subject.keywordsSarcin-ricin loop
dc.subject.keywordsPhytohormones
dc.subject.keywordsPokeweed
dc.subject.keywordsPhytolacca americana
dc.subject.keywordsNovel PAP
dc.subject.keywordsKPAP
dc.subject.keywordsPAP-I
dc.subject.keywordsPAP-isoforms
dc.subject.keywordsAbscisic acid
dc.subject.keywordsTEDA assembly
dc.subject.keywordsSWISS-MODEL
dc.subject.keywordsHaddock2.4
dc.subject.keywordsAutodock4
dc.subject.keywordsProtein purification
dc.subject.keywordsActive site
dc.subject.keywordsCatalytic arginine
dc.subject.keywordsPyMol
dc.subject.keywordsLong intron
dc.subject.keywordsLarge intron
dc.subject.keywordsDisulfide bonds
dc.subject.keywordsRIP interaction with the SRL
dc.subject.keywordsRT-qPCR
dc.subject.keywordsHomology modelling
dc.subject.keywordsMolecular docking
dc.subject.keywordsHudak lab
dc.titleCharacterization of KPAP, a Novel Pokeweed Antiviral Protein Isoform
dc.typeElectronic Thesis or Dissertation

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
deLaSelle_Fernand_J_2022_Masters.pdf
Size:
2.93 MB
Format:
Adobe Portable Document Format
Download
License bundle
Now showing 1 - 2 of 2
No Thumbnail Available
Name:
license.txt
Size:
1.87 KB
Format:
Plain Text
Description:
Download
No Thumbnail Available
Name:
YorkU_ETDlicense.txt
Size:
3.39 KB
Format:
Plain Text
Description:
Download

Collections

Biology

All items in the YorkSpace institutional repository are protected by copyright, with all rights reserved except where explicitly noted.