The genome of the Hi5 germ cell line from Trichoplusia ni, an agricultural pest and novel model for small RNA biology
- Boston University, United States
- University of Massachusetts Medical School, United States
Abstract
We report a draft assembly of the genome of Hi5 cells from the lepidopteran insect pest, Trichoplusia ni, assigning 90.6% of bases to one of 28 chromosomes and predicting 14,037 protein-coding genes. Chemoreception and detoxification gene families reveal T. ni-specific gene expansions that may explain its widespread distribution and rapid adaptation to insecticides. Transcriptome and small RNA data from thorax, ovary, testis, and the germline-derived Hi5 cell line show distinct expression profiles for 295 microRNA- and >393 piRNA-producing loci, as well as 39 genes encoding small RNA pathway proteins. Nearly all of the W chromosome is devoted to piRNA production, and T. ni siRNAs are not 2´-O-methylated. To enable use of Hi5 cells as a model system, we have established genome editing and single-cell cloning protocols. The T. ni genome provides insights into pest control and allows Hi5 cells to become a new tool for studying small RNAs ex vivo.
Article and author information
Author details
Funding
National Institutes of Health (GM65236)
- Phillip D Zamore
Howard Hughes Medical Institute (none)
- Phillip D Zamore
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Fu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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