Gene duplication is one of the major sources for the origin of new genes and new functions. However, how a new duplicate gene acquires functions by integrating into a pathway and results in adaptively important phenotypes has remained largely unknown.

Recently, WANG Wen and his colleagues from Kunming Institute of Zoology,Chinese Academy of Sciences, has systematically investigated the biological roles and the underlying molecular mechanism of the young kep1 gene family in the Drosophila melanogaster species subgroup to understand the origin and evolution of new genes with new functions. Sequence and expression analysis demonstrates that one of the new duplicates, nsr (novel spermatogenesis regulator), exhibits positive selection signals and novel subcellular localization pattern. Targeted mutagenesis and whole-transcriptome sequencing analysis provide evidence that nsr is required for male reproduction associated with sperm individualization, coiling, and structural integrity of the sperm axoneme via regulation of several Y chromosome fertility genes post-transcriptionally. The absence of nsr-like expression pattern and the presence of the corresponding cis-regulatory elements of the parental gene kep1 in the pre-duplication species Drosophila yakuba indicate that kep1 might not be ancestrally required for male functions and that nsr possibly has experienced the neofunctionalization process, facilitated by changes of trans-regulatory repertories.

These findings have been published on the famous genetic magazine PLoS Genetics and recommended as Featured Research. Once published, Nature Reviews Genetics has written a highlight to introduce it in the title of “young genes are essential too”, and regarded it has changed the traditional wisdom that essential genes are usually the older ones and revealed that “in fact essential genes are just as likely to be young, and that new genes can quickly integrate themselves into key pathways to take on essential roles.”

Link of Paper: http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1001255

Link of the Report of Nature Reviews Genetics: http://www.nature.com/nrg/journal/v12/n2/full/nrg2945.html