Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2015 Dec 29;112(52):15976-81. doi: 10.1073/pnas.1510461112. Epub 2015 Nov 23.

Evidence for extensive horizontal gene transfer from the draft genome of a tardigrade.

Author information

1
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599; tboothby@gmail.com.
2
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599;
3
Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599; Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599;
4
Eccles Institute of Human Genetics, University of Utah, Salt Lake City, UT 84112;
5
Cofactor Genomics, St. Louis, MO 63110.

Abstract

Horizontal gene transfer (HGT), or the transfer of genes between species, has been recognized recently as more pervasive than previously suspected. Here, we report evidence for an unprecedented degree of HGT into an animal genome, based on a draft genome of a tardigrade, Hypsibius dujardini. Tardigrades are microscopic eight-legged animals that are famous for their ability to survive extreme conditions. Genome sequencing, direct confirmation of physical linkage, and phylogenetic analysis revealed that a large fraction of the H. dujardini genome is derived from diverse bacteria as well as plants, fungi, and Archaea. We estimate that approximately one-sixth of tardigrade genes entered by HGT, nearly double the fraction found in the most extreme cases of HGT into animals known to date. Foreign genes have supplemented, expanded, and even replaced some metazoan gene families within the tardigrade genome. Our results demonstrate that an unexpectedly large fraction of an animal genome can be derived from foreign sources. We speculate that animals that can survive extremes may be particularly prone to acquiring foreign genes.

KEYWORDS:

genome; horizontal gene transfer; lateral gene transfer; stress tolerance; tardigrade

PMID:
26598659
PMCID:
PMC4702960
DOI:
10.1073/pnas.1510461112
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center