Use this URL to cite or link to this record in EThOS:
Title: A transcriptomics approach to understanding polymorphic and transcript level differences linked to isoquinoline alkaloid production in triploid varieties of Narcissus pseudonarcissus
Author: Pulman, Jane
ISNI:       0000 0004 5362 9806
Awarding Body: University of Liverpool
Current Institution: University of Liverpool
Date of Award: 2014
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Thesis embargoed until 01 Aug 2018
Access from Institution:
The Amaryllidaceae have characteristic isoquinoline alkaloids including galanthamine that is approved for treatment of Alzheimer’s disease. The daffodil (Narcissus pseudonarcissus) is an industrial source of this alkaloid. This project undertook analysis of the daffodil transcriptome as an approach to understanding this alkaloid biosynthetic pathway. Material from the basal plate of var. Carlton was analysed using the Roche 454 GS FLX Titanium and Illumina HiSeq platforms to assemble reference transcripts (45324 transcripts from 454, 165065 from Illumina). Annotation was via a bespoke BLAST pipeline utilizing UniProt, TAIR, Rfam and RefSeq. Further functional annotation and enrichment studies were carried out using the DAVID platform encompassing KEGG, GO and EC annotations. Illumina HiSeq sequencing of a second variety, Andrew’s Choice, was used alongside the reference transcripts to identify SNPs and transcript level differences. A bioinformatics method to determine ploidy indicated both varieties were triploid, in agreement with microscopy results. The level of selected transcripts was also assessed using qPCR. Several transcripts putatively involved in alkaloid biosynthesis were identified. Comp75950_c0_s1 showed homology to a C4H gene from peppers and could be involve in protocatechuic acid biosynthesis in daffodils. Two transcripts, Daff106212 and Contig1404, were predicted to catalyse the synthesis of norbelladine from protocatechuic acid and tyramine, and its subsequence conversion to 4’-O-methylnorbelladine. Finally, transcripts HDA57HA0AK3FX and Daff88927 were suggested for the final step in galanthamine biosynthesis, an intermolecular phenol coupling. This is the first transcriptomic comparison of two daffodil varieties and is an important resource for further investigation into genes involved in Amaryllidaceae alkaloid biosynthesis.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: Q Science (General)