Long-read genome assemblies for the study of chromosome size expansion in four Drosophila species
The Muller F Element is unusual among the autosomes in Drosophila melanogaster - while the chromosome is mostly heterochromatic, the distal 1.3 Mb region contains approximately 80 protein-coding genes that show a range of expression levels similar to genes on the euchromatic regions of other autosomes. In at least four Drosophila species, the F Element has expanded compared to D. melanogaster. This study uses long read sequencing data from Pacific Biosciences and Nanopore in conjunction with Hi-C data to improve the genome assemblies of D. kikkawai, D. takahashii, and D. bipectinata in order to investigate the factors that have contributed to the chromosome expansion and to assess the impact of the expansion on gene characteristics.