Callicarpa americana L. is a member of the Lamiaceae family with important ornamental and medicinal value. Although the chloroplast genome of Lamiaceae has been extensively studied, its mitochondrial genome remains unreported, limiting a comprehensive understanding of the phylogeny and genome evolution of Lamiaceae. In this study, the complete mitochondrial genome of C. americana was successfully assembled for the first time. The genome is 499,565 bp in length, showing a complex multi-branched closed-loop structure that contains 37 protein-coding genes, 23 tRNA genes, and 4 rRNA genes. The difference in mitochondrial genome size is relatively large compared to Orobanchaceae species, but the difference in GC content is not obvious. The expansion of genome size was mainly due to the accumulation of non-coding regions and repetitive sequences. Meanwhile, two pairs of long repetitive sequences (LR3 and LR5) mediated homologous recombination. The mitogenome was also identified; there were a total of 494 C-to-U RNA editing sites in protein-coding genes. In addition, 42 mitochondrial plastid DNA fragments (MTPTs) were detected, with a total length of 21,464 bp, accounting for 4.30% of the genome. Repeat sequence analysis showed that tetranucleotide SSR was the most abundant repeat type in the mitochondria of Lamiaceae. Phylogenetic analysis based on the alignment of 32 protein-coding gene sequences showed that Callicarpa is sister to the other eight species of Lamiaceae. This work fills an important gap by presenting the first complete mitochondrial genome of C. americana, providing an important data resource for further understanding the structural evolution, dynamic recombination mechanism, and phylogeny of the mitochondrial genome of Lamiaceae.

Apostasioideae, the early divergent subfamily of Orchidaceae, comprises Apostasia and Neuwiedia genera with approximately 20 species. Despite extensive research on Apostasioideae, previous studies have struggled to resolve taxonomic issues, particularly concerning the position of species within this subfamily. Here, we sequenced and annotated plastomes of Apostasia fujianica and Neuwiedia malipoensis, unveiling their phylogenetic relationships and shared plastome features with the other five published plastomes. We identified and analyzed the length, GC content, repeat sequences, and RSCU values of the chloroplast genomes. It is noteworthy that the chloroplast genome of N. malipoensis stands out as the largest among all known chloroplast genomes within the Apostasioideae subfamily, primarily due to contributions from both the LSC and SSC regions. Furthermore, our analysis revealed three unique structural rearrangements located approximately 10k–47k bp (ycf3–trnS-GCU) and 58k–59k bp(accD) in the LSC region and 118k–119k (ndhI) bp in the SSC region of the chloroplast genomes across all five species within the Apostasia genus, which presents a potential avenue for identifying distinctive chloroplast genetic markers, setting them apart from other orchid plants. And a total of four mutational hotspots (rpoC2, atpH, rps4, ndhK, and clpP) were identified. Moreover, our study suggested that Apostasia and Neuwiedia formed a monophyletic group, with Apostasia being sister to Neuwiedia. Within the Apostasia genus, five species were classified into two major clades, represented as follows: (A. odorata (A. shenzhenica and A. fujianica) (A. ramifera and A. wallichii)). These findings hold significance in developing DNA barcoding of Apostasioideae and contribute to the further phylogenetic understanding of Apostasioideae species.

Corolla movement is a typical plant movement behavior that enables plants to optimize pollination and adapt to environmental changes. Nevertheless, its molecular mechanism remains poorly understood. In the present study, we conduct a comprehensive transcriptome analysis of Mirabilis jalapa (Nyctaginaceae) corolla at five stages (AG-EG) to elucidate the regulatory networks underlying movement. The results showed that the differentially expressed genes (DEGs) were mainly associated with cellular processes, catalytic activity, MAPK signaling, plant hormone signal transduction, and photosynthesis-related pathways, highlighting their involvement in corolla dynamics. Transcriptome profiling further demonstrated that auxin, ethylene, and abscisic acid signaling pathways were key hormonal regulators of corolla movement. Moreover, Ca²⁺ transport genes (CNGCs and CMLs) and respiratory burst oxidase homologs (RBOHs) were significantly enriched, indicating that Ca²⁺–ROS signaling oscillations also play an important role in driving differential cell expansion and turgor changes. Transcription factor analysis also revealed the upregulation of WRKY2, WRKY22, and WRKY33, suggesting that WRKYs act as the critical transcriptional regulators linking ROS–Ca²⁺ signals with downstream gene expression. The reliability of RNA-Seq data was confirmed by RT-qPCR, which showed high consistency with transcriptome profiles. These findings suggested that corolla movement in M. jalapa is carried through the integration of hormonal pathways, Ca²⁺–ROS signaling, and WRKY-mediated transcriptional regulation. This research provided novel insights into the molecular basis of plant movement and established a foundation for further study on floral dynamics and adaptive strategies in angiosperms.