Genome size and lifestyle in gnesiotrochan rotifers

• Published in: Hydrobiologia Vol. 844; no. 1; pp. 105 - 115
• Main Authors: Brown, Patrick D., Walsh, Elizabeth J.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-11-2019; Springer; Springer Nature B.V
• Subjects: Biomedical and Life Sciences; Ecology; Flow cytometry; Freshwater & Marine Ecology; Genera; Genetic research; Genomes; Genomics; Gnesiotrocha; Hexarthra fennica; Life Sciences; Marine invertebrates; Noncoding DNA; Phylogeny; Rotifera; Rotifera XV; Species; Swimming; Taxonomy; Zoology; Coloniality; Flow cytometry; Free-swimming; Sessile; value
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1007/s10750-018-3873-8

Gnesiotrochan rotifers display a variety of life styles ranging from taxa with free-swimming larval and sessile adult stages to those with motile adult stages and colonial habits. Several explanations for the
C
-value enigma posit that genome size is correlated with lifestyle. To investigate this, 13 gnesiotrochan species representing nine genera were measured by flow cytometry. Genome sizes (1C) within Gnesiotrocha ranged from 0.05 pg (
Hexarthra mira
and
Hexarthra fennica
) to 0.25 pg (
Sinantherina ariprepes
). Genome sizes varied within genera and species; e.g., the
H. fennica
(El Huérfano, Mexico) genome was estimated to be 15% larger than that of
H. mira
and
H. fennica
(Keystone Wetland, TX, USA). Gnesiotrochan genome sizes are similar to those reported within Ploima, which range from 0.06 pg (
Brachionus rotundiformis
,
B. dimidiatus
) to 0.46 pg (
B. asplanchnoidis
). Within Gnesiotrocha, genome size was found to be significantly smaller in sessile versus motile species as well as in solitary versus colonial species. To account for phylogenetic background, linear mixed models with hierarchical taxonomic ranks showed that there is a taxonomic component underlying genome size. This study provides the first estimates of genome size within the superorder, providing a baseline for genomic and evolutionary studies within the group.