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Updated: May 23, 2026
09:11
Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions
Published on: October 2, 2018
Historical shifts and ecological patterns: rethinking genome size evolution in Coffea L
Sara Gonçalves Barbosa1,2, Mariana Cansian Sattler3, Maicon Nardino1,4
1Graduate Program in Genetics and Breeding, Federal University of Viçosa (UFV), Viçosa, Brazil.
Journal of Evolutionary Biology
|May 22, 2026
Summary
Genome size (GS) in coffee plants (Coffea) is not generally adaptive. While GS correlates with caffeine content (CAF) in one lineage, this appears to be due to historical events, not direct selection.
Area of Science:
- Plant Biology
- Evolutionary Biology
- Genomics
Background:
- Genome size (GS) is typically decoupled from organismal complexity (C-value paradox).
- Previous hypotheses suggest GS may be adaptive when linked to ecological traits.
- Diploid Coffea species exhibit modest but measurable GS variation, suitable for hypothesis testing.
Purpose of the Study:
- To investigate the phylogenetic correlation between GS and ecological traits in Coffea.
- To test if GS is phylogenetically associated with latitudinal range, elevational distribution, thermal tolerance, and caffeine content (CAF).
- To explore the evolutionary drivers of GS and CAF variation in Coffea.
Main Methods:
- Phylogenetic comparative methods using a well-resolved Coffea phylogeny.
- Analysis of GS correlation with ecological traits: latitudinal range, elevational distribution, thermal tolerance, and CAF.
- Comparative genomic analysis of two sequenced Coffea genomes (C. canephora and C. eugenioides) to assess gene copy number variation related to CAF.
Main Results:
- GS in Coffea shows significant phylogenetic signal.
- A positive correlation was found between GS and CAF, driven by a single lineage-specific shift in a West/Central African clade.
- No phylogenetic association was detected between GS and latitudinal range, elevational distribution, or thermal tolerance.
- Gene copy number variation did not correlate with CAF levels, suggesting regulatory changes are key to caffeine production.
Conclusions:
- The findings do not support a generalized adaptive role for GS evolution in Coffea.
- The observed GS-CAF association is likely due to lineage-specific historical events, not direct adaptive responses.
- Caffeine production evolution in Coffea appears primarily regulated by genetic changes beyond gene duplication.
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