Multi-tissue transcriptome analysis of two Begonia species reveals dynamic patterns of evolution in the chalcone synthase gene family

Katie Emelianova, Andrea Martínez Martínez, Lucia Campos-Dominguez, Catherine Kidner, Work enabled by Edinburgh Genomics

Research output: Contribution to journalArticlepeer-review

Abstract

Begonia is an important horticultural plant group, as well as one of the most speciose Angiospermgenera, with over 2000 described species. Genus wide studies of genome size have shown that Begonia has a highly variable genome size, and analysis of paralog pairs has previously suggested that Begonia underwent a whole genome duplication. We address the contribution of gene duplication to the generation of diversity in Begonia using a multi-tissue RNA-seq approach. We chose to focus on chalcone synthase (CHS), a gene family having been shown to be involved in biotic and abiotic stress responses in other plant species, in particular its importance in maximising the use of variable light levels in tropical plants. We used RNA-seq to sample six tissues across two closely related but ecologically and morphologically divergent species, Begonia conchifolia and B. plebeja, yielding17,012 and 19,969 annotated unigenes respectively. We identified the chalcone synthase gene family members in our Begonia study species, as well as in Hillebrandia sandwicensis, the monotypicsister genus to Begonia, Cucumis sativus, Arabidopsis thaliana, and Zea mays. Phylogenetic analysis suggested the CHS gene family has high duplicate turnover, all members of CHS identified in Begonia arising recently, after the divergence of Begonia and Cucumis. Expression profiles were similar within orthologous pairs, but we saw high inter-ortholog expression variation. Sequence analysis showed relaxed selective constraints on some ortholog pairs, with substitutions at conserved sites. Evidence of pseudogenisation and species specific duplication indicate that lineage specific differences are already beginning to accumulate since the divergence of our study species. We conclude that there is evidence for a role of gene duplication in generating diversity through sequence and expression divergence in Begonia
Original languageEnglish
Article number17773
Number of pages12
JournalScientific Reports
Volume11
Issue number1
DOIs
Publication statusPublished - 7 Sep 2021

Fingerprint

Dive into the research topics of 'Multi-tissue transcriptome analysis of two Begonia species reveals dynamic patterns of evolution in the chalcone synthase gene family'. Together they form a unique fingerprint.

Cite this