Understanding the Posttranscriptional Regulation of Plant Responses to Abiotic Stress
Name:
PhD Dissertation_Sahar Abdul-Aziz AlShareef_Summer 2017.pdf
Size:
7.684Mb
Format:
PDF
Description:
PhD Dissertation_Sahar Abdul-Aziz AlShareef_Summer 2017
Type
DissertationAuthors
Alshareef, Sahar
Advisors
Mahfouz, Magdy M.
Committee members
Al-Babili, Salim
Pardo, Jose M.
Benhamed, Moussa

Ghaffour, NorEddine

Program
BioscienceDate
2017-06Embargo End Date
2018-06-20Permanent link to this record
http://hdl.handle.net/10754/625070
Metadata
Show full item recordAccess Restrictions
At the time of archiving, the student author of this dissertation opted to temporarily restrict access to it. The full text of this dissertation became available to the public after the expiration of the embargo on 2018-06-20.Abstract
Constitutive and alternative splicing of pre-mRNAs from multiexonic genes controls the diversity of the proteome; these precisely regulated processes also fine-tune responses to cues related to growth, development, and biotic and abiotic stresses. Recent work showed that AS is pervasive across plant species, with more than 60% of intron-containing genes producing different isoforms. Mammalian cell-based assays have discovered various AS small-molecule inhibitors that perturb splicing and thereby provide invaluable tools for use as chemical probes to uncover the molecular underpinnings of splicing regulation and as potential anticancer compounds. Here, I show that the macrolide Pladienolide B (PB) and herboxidiene (GEX1A) inhibits both constitutive and alternative splicing, mimics an abiotic stress signal, and activates the abscisic acid (ABA) pathway in plants. Moreover, PB and GEX1A activate genome-wide transcriptional patterns involved in abiotic stress responses in plants. PB and GEX1A treatment triggered the ABA signaling pathway, activated ABA-inducible promoters, and led to stomatal closure. Interestingly, PB and GEX1A elicited similar cellular changes, including alterations in the patterns of transcription and splicing, suggesting that these compounds might target the same spliceosome complex in plant cells. This work establishes PB and GEX1A as potent splicing inhibitors in plants that can be used to probe the assembly, dynamics, and molecular functions of the spliceosome and to study the interplay between splicing stress and abiotic stresses, as well as having potential biotechnological applications.ae974a485f413a2113503eed53cd6c53
10.25781/KAUST-1UZ75