A China Agricultural University-led team has generated a telomere-to-telomere genome assembly of the maize genome. The maize genome is known to be highly repetitive — it is estimated to contain with more than 80 percent repetitive sequences — making it a model for complex genomes as well as a key crop. As they report in Nature Genetics, the researchers used a combination of ultralong Oxford Nanopore Technology and PacBio HiFi reads to put together their assembly of the 10 chromosomes of the Mo17 inbred maize line. In all, the assembly generated is 2,178.6 Mb in size with a high base accuracy, the researchers report. In particular, they note that they were able to disentangle various highly repetitive sequences. For instance, they generated complete assemblies for all the centromeres as well as for the entire nucleolus organizer region, which contains some 3,000 rDNA copies. With this assembly, the researchers write in their paper that they "[aimed] to uncover the complex genomic 'dark matter' and to decode the extraordinary repetitive regions of higher plant genomes.
Maize Assembly Goes Telomere to Telomere
Jun 16, 2023