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Title: Evolution of l ‐ DOPA 4,5‐dioxygenase activity allows for recurrent specialisation to betalain pigmentation in Caryophyllales
Summary

The evolution oflDOPA4,5‐dioxygenase activity, encoded by the geneDODA, was a key step in the origin of betalain biosynthesis in Caryophyllales. We previously proposed thatlDOPA4,5‐dioxygenase activity evolved via a single Caryophyllales‐specific neofunctionalisation event within theDODAgene lineage. However, this neofunctionalisation event has not been confirmed and theDODAgene lineage exhibits numerous gene duplication events, whose evolutionary significance is unclear.

To address this, we functionally characterised 23 distinctDODAproteins forlDOPA4,5‐dioxygenase activity, from four betalain‐pigmented and five anthocyanin‐pigmented species, representing key evolutionary transitions across Caryophyllales. By mapping these functional data to an updatedDODAphylogeny, we then explored the evolution oflDOPA4,5‐dioxygenase activity.

We find that lowlDOPA4,5‐dioxygenase activity is distributed across theDODAgene lineage. In this context, repeated gene duplication events within theDODAgene lineage give rise to polyphyletic occurrences of elevatedlDOPA4,5‐dioxygenase activity, accompanied by convergent shifts in key functional residues and distinct genomic patterns of micro‐synteny.

In the context of an updated organismal phylogeny and newly inferred pigment reconstructions, we argue that repeated convergent acquisition of elevatedlDOPA4,5‐dioxygenase activity is consistent with recurrent specialisation to betalain synthesis in Caryophyllales.

 
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NSF-PAR ID:
10456853
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
227
Issue:
3
ISSN:
0028-646X
Page Range / eLocation ID:
p. 914-929
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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