Effect of phytoglobin1 (Pgb1) expression on the regeneration of maize (Zea mays L.) root quiescent centers (QCs) during hypoxia
| dc.contributor.author | Rathnayaka Pathiranage, Rajitha Gayan Lakmini | |
| dc.contributor.examiningcommittee | Hill, Robert D. (Plant Science) | en_US |
| dc.contributor.examiningcommittee | Renault, Sylvie (Biological Sciences) | en_US |
| dc.contributor.supervisor | Stasolla, Claudio | |
| dc.date.accessioned | 2023-06-01T20:04:39Z | |
| dc.date.available | 2023-06-01T20:04:39Z | |
| dc.date.copyright | 2023-05-19 | |
| dc.date.issued | 2023-05-19 | |
| dc.date.submitted | 2023-05-19T16:45:31Z | en_US |
| dc.degree.discipline | Plant Science | en_US |
| dc.degree.level | Master of Science (M.Sc.) | en_US |
| dc.description.abstract | Maize (Zea mays) root quiescent center (QC) cells deteriorate during hypoxic treatment, halting root growth. Over-expression of the Phytoglobin1 ZmPgb1.1 is known to alleviate these effects through the retention of the auxin flow along the root profile required for QC specification. To elucidate QC-specific hypoxia responses and whether ZmPgb1.1 exercises a direct role on QC stem cells, we performed a QC functionality test. This was done by estimating the ability of QCs to regenerate a root in-vitro in a hypoxic environment. Hypoxia decreased the functionality of the QCs by depressing the expression of several genes participating in the synthesis and response of auxin. This was accompanied by a decrease in DR5 signal in oxygen deprived QCs and a consequent suppression of QC markers and genes of jasmonic acid (JA) synthesis and signaling. Over-expression of ZmPgb1.1 mitigated all these responses. Through pharmacological alterations of auxin and JA (through 1-Naphthaleneacetic acid and methyl jasmonate, respectively), it is demonstrated that both compounds are required for QC functionality under hypoxia, and that JA acts downstream of auxin during QC regeneration. A model is proposed whereby the ZmPgb1.1 maintenance of auxin in hypoxic QCs is determinant for the retention of their functionality, with JA supporting the regeneration of roots from the QCs. | en_US |
| dc.description.note | October 2023 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/37371 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Waterlogging | en_US |
| dc.subject | Hypoxia | en_US |
| dc.subject | Maize | en_US |
| dc.subject | Phytoglobin | en_US |
| dc.title | Effect of phytoglobin1 (Pgb1) expression on the regeneration of maize (Zea mays L.) root quiescent centers (QCs) during hypoxia | en_US |
| dc.type | master thesis | en_US |
| local.subject.manitoba | no | en_US |
| oaire.awardNumber | 126542 | en_US |
| oaire.awardTitle | Discovery | en_US |
| oaire.awardURI | https://www.nserc-crsng.gc.ca/Professors-Professeurs/Grants-Subs/DGIGP-PSIGP_eng.asp | en_US |
| project.funder.identifier | http://dx.doi.org/10.13039/501100000038 | en_US |
| project.funder.name | NSERC | en_US |