Frontiers in Plant Science (Nov 2023)

Telomere-to-telomere and haplotype-resolved genome assembly of the Chinese cork oak (Quercus variabilis)

  • Longxin Wang,
  • Lei-Lei Li,
  • Li Chen,
  • Ren-Gang Zhang,
  • Shi-Wei Zhao,
  • Han Yan,
  • Jie Gao,
  • Xue Chen,
  • Yu-Jun Si,
  • Zhe Chen,
  • Haibo Liu,
  • Xiao-Man Xie,
  • Wei Zhao,
  • Biao Han,
  • Xiaochun Qin,
  • Kai-Hua Jia

DOI
https://doi.org/10.3389/fpls.2023.1290913
Journal volume & issue
Vol. 14

Abstract

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The Quercus variabilis, a deciduous broadleaved tree species, holds significant ecological and economical value. While a chromosome-level genome for this species has been made available, it remains riddled with unanchored sequences and gaps. In this study, we present a nearly complete comprehensive telomere-to-telomere (T2T) and haplotype-resolved reference genome for Q. variabilis. This was achieved through the integration of ONT ultra-long reads, PacBio HiFi long reads, and Hi-C data. The resultant two haplotype genomes measure 789 Mb and 768 Mb in length, with a contig N50 of 65 Mb and 56 Mb, and were anchored to 12 allelic chromosomes. Within this T2T haplotype-resolved assembly, we predicted 36,830 and 36,370 protein-coding genes, with 95.9% and 96.0% functional annotation for each haplotype genome. The availability of the T2T and haplotype-resolved reference genome lays a solid foundation, not only for illustrating genome structure and functional genomics studies but also to inform and facilitate genetic breeding and improvement of cultivated Quercus species.

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