Musella lasiocarpa (MLA, 2n = 18, Musaceae) is an endangered species native to south-western China. We assembled its haplotype-resolved, telomere-to-telomere genomes with a genome size of 503.6 Mb consisting of 52.8% repetitive DNA. A 134 bp tandem repeat, Mlcen, was identified at all centromeres, and telomere sequences were present at 30 of 36 assembled pseudo-chromosome ends. The distal gene-rich regions display high synteny, whereas retrotransposon polymorphisms between haplotypes occurred throughout chromosomes, contributing to diversity. Phylogenetic analysis shows MLA diverged from Ensete 42 million years ago, and together they share a common ancestor with Musa. Among 35,312 protein-coding genes, 14 up-regulated and 34 down-regulated transcription factors were identified under cold treatment. This high-quality genomic resource advances our understanding of MLA chromosomal evolution characterized by structural variations, repetitive DNA dynamics, and cold-responsive genes at both haplotype and species levels; and enables genome-assisted improvement of more resilient crops such as bananas and Ensete.
Liu et al. (Wed,) studied this question.