Zilov Danil, Mandáková Terezie, Popova Marina, Lysak Martin A, Windham Michael D, Brukhin Vladimir
Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SA, UK.
ITMO University, ChemBio Cluster Lomonosova 9, Saint Petersburg 197101, Russia.
G3 (Bethesda). 2025 Jul 9;15(7). doi: 10.1093/g3journal/jkaf117.
Boechera falcata (Turcz.) Al-Shehbaz, previously known as Arabis turczaninowii Ledeb., is a herbaceous perennial of the East Siberian, boreal-steppe ecotype. It is the sole species of the diverse genus Boechera found on the Eurasian continent, with all other species endemic to North America and Greenland. Likely migrating from North America to Eastern Siberia via the Bering Land Bridge during the Pleistocene glaciation, B. falcata presents a unique case for genomic study. The genus Boechera is notable for its many allodiploid and triploid apomicts, which have arisen through complex hybridization of sexual species and ecotypes. To date, only the genomes of 2 American Boechera species, B. stricta and B. retrofracta, have been sequenced and analyzed. In this study, we sequenced, assembled to the chromosome level, and analyzed the highly homozygous 189.36 Mb genome of B. falcata (2n = 14). Molecular phylogenetic analysis of nuclear and organelle genomes revealed a high degree of relatedness to North American relatives. Cytogenetic analysis identified all 22 genomic blocks of crucifers, showing that 5 of the 7 B. falcata chromosomes are collinear with their ancestral counterparts, while 2 have undergone inversions. Allelic analysis of the apomixis marker APOLLO gene revealed that B. falcata contains only sex alleles. The availability of the B. falcata genome will advance studies of the evolution and phylogeny of Brassicaceae species and the mechanisms of apomixis, providing a crucial resource for future research in plant genetics and breeding.
镰叶岩荠（Boechera falcata (Turcz.) Al-Shehbaz），以前被称为图氏岩荠（Arabis turczaninowii Ledeb.），是一种具有东伯利亚寒温带草原生态型的多年生草本植物。它是在欧亚大陆发现的多歧岩荠属（Boechera）中唯一的物种，该属的所有其他物种都分布于北美和格陵兰岛。在更新世冰川期，镰叶岩荠可能通过白令陆桥从北美迁移到东西伯利亚，这为基因组研究提供了一个独特的案例。岩荠属以其众多的异源二倍体和三倍体无融合生殖体而闻名，这些无融合生殖体是通过有性物种和生态型的复杂杂交产生的。迄今为止，仅对2种美洲岩荠属物种，即坚挺岩荠（B. stricta）和反折岩荠（B. retrofracta）的基因组进行了测序和分析。在本研究中，我们对镰叶岩荠（2n = 14）高度纯合的189.36 Mb基因组进行了测序、组装到染色体水平并进行了分析。对核基因组和细胞器基因组的分子系统发育分析揭示了与北美亲缘种的高度相关性。细胞遗传学分析确定了十字花科植物的所有22个基因组块，表明镰叶岩荠的7条染色体中有5条与其祖先对应染色体是共线的，而另外2条发生了倒位。对无融合生殖标记APOLLO基因的等位基因分析表明，镰叶岩荠仅含有性等位基因。镰叶岩荠基因组的可得性将推动十字花科物种进化和系统发育以及无融合生殖机制的研究，为未来植物遗传学和育种研究提供关键资源。
