A new approach for comprehensively describing heterogametic sex chromosomes.

ABSTRACT: Notwithstanding the rapid developments in sequencing techniques, Y and W sex chromosomes have still been mostly excluded from whole genome sequencing projects due to their high repetitive DNA content. Therefore, Y and W chromosomes are poorly described in most species despite their biological importance. Several methods were developed for identifying Y or W-linked sequences among unmapped scaffolds. However, it is not enough to discover functional regions from short unmapped scaffolds. Here, we provide a new and simple strategy based on k-mer comparison for comprehensive analysis of the W chromosome in Bombyx mori. Using this novel method, we effectively assembled de novo 1281?W-derived genome contigs (totaling 1.9?Mbp), and identified 156?W-linked transcript RNAs and 345?W-linked small RNAs. This method will help in the elucidation of mechanisms of sexual development and exploration of W chromosome biological functions, and provide insights into the evolution of sex chromosomes. Moreover, we showed this method can be employed in identifying heterogametic sex chromosomes (W and Y chromosomes) in many other species where genomic information is still scarce.

SUBMITTER: Li S 

PROVIDER: S-EPMC6105102 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature