@article{Nozawa01112021,
author = {Nozawa, Masafumi and Minakuchi, Yohei and Satomura, Kazuhiro and Kondo, Shu and Toyoda, Atsushi and Tamura, Koichiro}, 
title = {Shared evolutionary trajectories of three independent neo-sex chromosomes in Drosophila},
volume = {31}, 
number = {11}, 
pages = {2069-2079}, 
year = {2021}, 
doi = {10.1101/gr.275503.121}, 
abstract ={Dosage compensation (DC) on the X Chromosome counteracts the deleterious effects of gene loss on the Y Chromosome. However, DC is not efficient if the X Chromosome also degenerates. This indeed occurs in Drosophila miranda, in which both the neo-Y and the neo-X are under accelerated pseudogenization. To examine the generality of this pattern, we investigated the evolution of two additional neo-sex chromosomes that emerged independently in D. albomicans and D. americana and reanalyzed neo-sex chromosome evolution in D. miranda. Comparative genomic and transcriptomic analyses revealed that the pseudogenization rate on the neo-X is also accelerated in D. albomicans and D. americana although to a lesser extent than in D. miranda. In males, neo-X-linked genes whose neo-Y-linked homologs are pseudogenized tended to be up-regulated more than those whose neo-Y-linked homologs remain functional. Moreover, genes under strong functional constraint and genes highly expressed in the testis tended to remain functional on the neo-X and neo-Y, respectively. Focusing on the D. miranda and D. albomicans neo-sex chromosomes that emerged independently from the same autosome, we further found that the same genes tend to become pseudogenized in parallel on the neo-Y. These genes include Idgf6 and JhI-26, which may be unnecessary or even harmful in males. Our results indicate that neo-sex chromosomes in Drosophila share a common evolutionary trajectory after their emergence, which may prevent sex chromosomes from being an evolutionary dead end.}, 
URL = {http://genome.cshlp.org/content/31/11/2069.abstract}, 
eprint = {http://genome.cshlp.org/content/31/11/2069.full.pdf+html}, 
journal = {Genome Research} 
}