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Title: Comparative DNA sequence analyses of Pyramimonas parkeae (Prasinophyceae) chloroplast genomes

Prasinophytes form a paraphyletic assemblage of early diverging green algae, which have the potential to reveal the traits of the last common ancestor of the main two green lineages: (i) chlorophyte algae and (ii) streptophyte algae. Understanding the genetic composition of prasinophyte algae is fundamental to understanding the diversification and evolutionary processes that may have occurred in both green lineages. In this study, we sequenced the chloroplast genome ofPyramimonas parkeaeNIES254 and compared it with that ofP. parkeaeCCMP726, the only other fully sequencedP. parkeaechloroplast genome. The results revealed thatP. parkeaechloroplast genomes are surprisingly variable. The chloroplast genome ofNIES254 was larger than that ofCCMP726 by 3,204 bp, theNIES254 large single copy was 288 bp longer, the small single copy was 5,088 bp longer, and theIRwas 1,086 bp shorter than that ofCCMP726. Similarity values of the two strains were almost zero in four large hot spot regions. Finally, the strains differed in copy number for three protein‐coding genes:ycf20,psaC, andndhE. Phylogenetic analyses using 16S and 18SrDNAandrbcLsequences resolved a clade consisting of these twoP. parkeaestrains and a clade consisting of these plus otherPyramimonasisolates. These results are consistent with past studies indicating that prasinophyte chloroplast genomes display a higher level of variation than is commonly found among land plants. Consequently, prasinophyte chloroplast genomes may be less useful for inferring the early history of Viridiplantae than has been the case for land plant diversification.

 
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NSF-PAR ID:
10026649
Author(s) / Creator(s):
 ;  ;
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Journal of Phycology
Volume:
53
Issue:
2
ISSN:
0022-3646
Page Range / eLocation ID:
p. 415-424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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