Two families of non-LTR retrotransposons, Syrinx and Daphne, from the Darwinulid ostracod, Darwinula stevensoni
Two families of non-LTR retrotransposons, Syrinx and Daphne, from the Darwinulid ostracod, Darwinula stevensoni
Date
2005-12-15
Authors
Schon, Isabelle
Arkhipova, Irina R.
Arkhipova, Irina R.
Linked Authors
Alternative Title
Citable URI
As Published
Date Created
Location
DOI
Related Materials
Replaces
Replaced By
Keywords
Mobile genetic elements
Asexual reproduction
Asexual reproduction
Abstract
Two novel families of non-LTR retrotransposons, named Syrinx and Daphne, were cloned and
characterized in a putative ancient asexual ostracod Darwinula stevensoni. Phylogenetic analysis reveals
that Daphne is the founding member of a novel clade of non-LTR retroelements, which also contains newly
described families from the sea urchin and the silkworm and forms a sister clade to L2-like elements. The
Syrinx family of non-LTR retrotransposons exhibits evidence of relatively recent activity, manifested in high
levels of sequence similarity between individual copies and a three- to ten-fold excess of synonymous
substitutions, which is indicative of purifying selection. The Daphne family may have very few copies with
intact open reading frames, and exhibits neutral within-family ratio of non-synonymous to synonymous
substitutions. It can additionally be characterized by formation of inverted truncated head-to-head
structures. All of these features make recent activity less likely than in the Syrinx family. Our results are
discussed in light of the evolutionary consequences of long-term asexuality in general and in Darwinula
stevensoni in particular.
Description
Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Gene 371 (2006): 296-307, doi:10.1016/j.gene.2005.12.007.