TY - JOUR
T1 - Genome sequences of five Sitopsis species of Aegilops and the origin of polyploid wheat B subgenome
AU - Li, Lin-Feng
AU - Zhang, Zhi-Bin
AU - Wang, Zhen-Hui
AU - Li, Ning
AU - Sha, Yan
AU - Wang, Xin-Feng
AU - Ding, Ning
AU - Li, Yang
AU - Zhao, Jing
AU - Wu, Ying
AU - Gong, Lei
AU - Mafessoni, Fabrizio
AU - Levy, Avraham A
AU - Liu, Bao
PY - 2022/3/7
Y1 - 2022/3/7
N2 - Common wheat (Triticum aestivum, BBAADD) is a major staple food crop worldwide. The diploid progenitors of the A and D subgenomes have been unequivocally identified; that of B, however, remains ambiguous and controversial but is suspected to be related to species of Aegilops, section Sitopsis. Here, we report the assembly of chromosome-level genome sequences of all five Sitopsis species, namely Aegilops bicornis, Ae. longissima, Ae. searsii, Ae. sharonensis, and Ae. speltoides, as well as the partial assembly of the Amblyopyrum muticum (synonym Aegilops mutica) genome for phylogenetic analysis. Our results reveal that the donor of the common wheat B subgenome is a distinct, and most probably extinct, diploid species that diverged from an ancestral progenitor of the B lineage to which the still extant Ae. speltoides and Am. muticum belong. In addition, we identified interspecific genetic introgressions throughout the evolution of the Triticum/Aegilops species complex. The five Sitopsis species have various assembled genome sizes (4.11–5.89 Gb) with high proportions of repetitive sequences (85.99%–89.81%); nonetheless, they retain high collinearity with other genomes or subgenomes of species in the Triticum/Aegilops complex. Differences in genome size were primarily due to independent post-speciation amplification of transposons. We also identified a set of Sitopsis genes pertinent to important agronomic traits that can be harnessed for wheat breeding. These newly assembled genome resources provide a new roadmap for evolutionary and genetic studies of the Triticum/Aegilops complex, as well as for wheat improvement.
AB - Common wheat (Triticum aestivum, BBAADD) is a major staple food crop worldwide. The diploid progenitors of the A and D subgenomes have been unequivocally identified; that of B, however, remains ambiguous and controversial but is suspected to be related to species of Aegilops, section Sitopsis. Here, we report the assembly of chromosome-level genome sequences of all five Sitopsis species, namely Aegilops bicornis, Ae. longissima, Ae. searsii, Ae. sharonensis, and Ae. speltoides, as well as the partial assembly of the Amblyopyrum muticum (synonym Aegilops mutica) genome for phylogenetic analysis. Our results reveal that the donor of the common wheat B subgenome is a distinct, and most probably extinct, diploid species that diverged from an ancestral progenitor of the B lineage to which the still extant Ae. speltoides and Am. muticum belong. In addition, we identified interspecific genetic introgressions throughout the evolution of the Triticum/Aegilops species complex. The five Sitopsis species have various assembled genome sizes (4.11–5.89 Gb) with high proportions of repetitive sequences (85.99%–89.81%); nonetheless, they retain high collinearity with other genomes or subgenomes of species in the Triticum/Aegilops complex. Differences in genome size were primarily due to independent post-speciation amplification of transposons. We also identified a set of Sitopsis genes pertinent to important agronomic traits that can be harnessed for wheat breeding. These newly assembled genome resources provide a new roadmap for evolutionary and genetic studies of the Triticum/Aegilops complex, as well as for wheat improvement.
UR - http://www.scopus.com/inward/record.url?scp=85123737133&partnerID=8YFLogxK
U2 - 10.1016/j.molp.2021.12.019
DO - 10.1016/j.molp.2021.12.019
M3 - Article
C2 - 34979290
SN - 1674-2052
VL - 15
SP - 488
EP - 503
JO - Molecular Plant
JF - Molecular Plant
IS - 3
ER -