Heterologous overexpression of PfBBX8 in Arabidopsis thaliana significantly promoted flowering, whereas a natural C/T mutation substantially delayed flowering.
The construction of a high-density genetic map and identification of PfBBX8 provides valuable insights into the flowering regulation and molecular breeding of Perilla frutescens.
Perilla frutescens (L.) is an important plant in traditional Chinese medicine and ornamental horticulture. However, classical genetic studies in this species remain limited. To perform QTL mapping for its important traits, the whole-genome resequencing of an F2 segregating population (n = 140) was conducted to construct a high-density genetic map. The sequencing generated 2,865.46 Gb of clean data. And the resulting high-density genetic map comprised 1,321.55 cM across 20 linkage groups, consisting of 2,289 recombination bins that integrated 9,599,671 SNP markers. The map exhibited an average interval of 0.58 cM per marker. To identify candidate genes associated with flowering traits, integrative QTL analysis delineated four consensus QTL regions associated with flower bud differentiation and initial flowering time. The 122 candidate genes were identified in these regions, including PfBBX8, a member of the CCT domain-containing family. Gene Ontology (GO) enrichment analysis suggested that PfBBX8 may serve as a key regulator in photoperiod-mediated flowering pathways. Heterologous overexpression of PfBBX8 in Arabidopsis thaliana significantly promoted flowering, whereas a natural C/T mutation in PfBBX8 resulted in substantially delayed flowering relative to transgenic lines overexpressing the wild-type allele. Moreover, overexpression of PfBBX8 upregulated downstream flowering integrators such as CO and FT, indicating its role in activating flowering pathways. These findings provide valuable high-density genetic map and flowering regulation for molecular breeding in Perilla.
Zou et al. (Mon,)は、シソ（Perilla frutescens）の開花特性に関する別の研究を行いました（n=140）。PfBBX8の過剰発現と野生型アレル/Natural C/T変異が開花時間および花芽分化に与える影響を評価しました。アラビドプシス（Arabidopsis thaliana）におけるPfBBX8の異種過剰発現は開花を有意に促進しましたが、自然のC/T変異は開花を大幅に遅延させました。