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Title: Evolution and expression of core SWI / SNF genes in red algae

Red algae are the oldest identifiable multicellular eukaryotes, with a fossil record dating back more than a billion years. During that time two major rhodophyte lineages, bangiophytes and florideophytes, have evolved varied levels of morphological complexity. These two groups are distinguished, in part, by different patterns of multicellular development, with florideophytes exhibiting a far greater diversity of morphologies. Interestingly, during their long evolutionary history, there is no record of a rhodophyte achieving the kinds of cellular and tissue‐specific differentiation present in other multicellular algal lineages. To date, the genetic underpinnings of unique aspects of red algal development are largely unexplored; however, they must reflect the complements and patterns of expression of key regulatory genes. Here we report comparative evolutionary and gene expression analyses of core subunits of theSWI/SNFchromatin‐remodeling complex, which is implicated in cell differentiation and developmental regulation in more well studied multicellular groups. Our results suggest that a single, canonicalSWI/SNFcomplex was present in the rhodophyte ancestor, with gene duplications and evolutionary diversification ofSWI/SNFsubunits accompanying the evolution of multicellularity in the common ancestor of bangiophytes and florideophytes. Differences in howSWI/SNFchromatin remodeling evolved subsequently, in particular gene losses and more rapid divergence ofSWI3 andSNF5 in bangiophytes, could help to explain why they exhibit a more limited range of morphological complexity than their florideophyte cousins.

 
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PAR ID:
10077985
Author(s) / Creator(s):
 ;  ;  ;  ;  ;
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Journal of Phycology
Volume:
54
Issue:
6
ISSN:
0022-3646
Page Range / eLocation ID:
p. 879-887
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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