New genes often acquire male-specific functions but rarely become essential in Drosophila
- Shu Kondo1,7,
- Jeffrey Vedanayagam2,7,
- Jaaved Mohammed2,3,4,
- Sogol Eizadshenass5,
- Lijuan Kan2,
- Nan Pang2,
- Rajaguru Aradhya2,
- Adam Siepel6,
- Josefa Steinhauer5 and
- Eric C. Lai2
- 1Invertebrate Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan;
- 2Department of Developmental Biology, Sloan-Kettering Institute, New York, New York 10065, USA;
- 3Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York 14853, USA;
- 4Tri-Institutional Training Program in Computational Biology and Medicine, New York, New York 10021, USA;
- 5Department of Biology, Yeshiva University, New York, New York 10033, USA;
- 6Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
- Corresponding authors: skondo{at}nig.ac.jp, laie{at}mskcc.org
-
↵7 These authors contributed equally to this work.
Abstract
Relatively little is known about the in vivo functions of newly emerging genes, especially in metazoans. Although prior RNAi studies reported prevalent lethality among young gene knockdowns, our phylogenomic analyses reveal that young Drosophila genes are frequently restricted to the nonessential male reproductive system. We performed large-scale CRISPR/Cas9 mutagenesis of “conserved, essential” and “young, RNAi-lethal” genes and broadly confirmed the lethality of the former but the viability of the latter. Nevertheless, certain young gene mutants exhibit defective spermatogenesis and/or male sterility. Moreover, we detected widespread signatures of positive selection on young male-biased genes. Thus, young genes have a preferential impact on male reproductive system function.
Keywords
Footnotes
-
Supplemental material is available for this article.
-
Article is online at http://www.genesdev.org/cgi/doi/10.1101/gad.303131.117.
- Received June 11, 2017.
- Accepted September 12, 2017.
This article is distributed exclusively by Cold Spring Harbor Laboratory Press for the first six months after the full-issue publication date (see http://genesdev.cshlp.org/site/misc/terms.xhtml). After six months, it is available under a Creative Commons License (Attribution-NonCommercial 4.0 International), as described at http://creativecommons.org/licenses/by-nc/4.0/.
