Search Results (3)

B-box (BBX) genes, as zinc finger transcription factors (TFs), play essential roles in regulating plant growth and development. In this study, we identified 23 BBX genes in the pomegranate (Punica granatum L.) genome. These genes were classified into five groups based on the distribution of conserved domains and phylogenetic relationships. Each PgBBX group exhibited similar molecular weights, theoretical isoelectric points (pI), gene structures, and conserved motif distributions compared with BBX members in Arabidopsis and Chinese white pear in corresponding groups. Syntenic analysis revealed segmental duplications of eight PgBBX gene pairs within the pomegranate genome. Additionally, twenty-seven and thirty-one orthologous BBX pairs were identified between PgBBX and AtBBX, and PgBBX and PbBBX, respectively. Promoter analysis revealed the presence of five types of cis-acting elements responding to light, phytohormones, stress, developmental signaling, and potential transcription factors (TFs). GO enrichment analysis confirmed that most PgBBX genes function as TF involved in plant growth and development. RNA-seq data indicated that PgBBX5 was primarily expressed in leaves and flowers, with increased expression in different fruit tissues during ripening. Moreover, PgBBX5 showed a high degree of sequence similarity with anthocyanin-related homologs, including AtBBX24, PhBBX24, FaBBX24, MdCOL4, and PyBBX24. During the ripening of ‘Tunisia’ fruits, PgBBX5 expression was positively correlated with the dynamic changes in anthocyanin content and the expression of key anthocyanin biosynthetic and transport genes. Furthermore, subcellular localization suggested that PgBBX5 encodes a nuclear-localized protein. This study provides a comprehensive characterization of the PgBBX family, offering valuable insights into the mechanisms underlying anthocyanin accumulation during pomegranate fruit ripening. Full article

In recent years, there has been a growing interest in plant pigments as readily available nutraceuticals. Photosynthetic pigments, specifically chlorophylls and carotenoids, renowned for their non-toxic antioxidant properties, are increasingly finding applications beyond their health-promoting attributes. Consequently, there is an ongoing need for cost-effective methods of isolation. This study employs a co-precipitation method to synthesize magnetic iron oxide nanoparticles. Scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS) confirms that an aqueous environment and oxidizing conditions yield nanosized iron oxide with particle sizes ranging from 80 to 140 nm. X-ray photoelectron spectroscopy (XPS) spectra indicate the presence of hydrous iron oxide FeO(OH) on the surface of the nanosized iron oxide. The Brunauer–Emmett–Teller (BET) surface area of obtained nanomaterial was 151.4 m² g⁻¹, with total pore volumes of pores 0.25 cm³ g⁻¹ STP. The material, designated as iron oxide nanoparticles (IONPs), serves as an adsorbent for magnetic solid phase extraction (MSPE) and isolation of photosynthetic pigments (chlorophyll a, lutein) from extracts of higher green plants (Mentha piperita L., Urtica dioica L.). Sorption of chlorophyll a onto the nanoparticles is confirmed using UV–vis spectroscopy, Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS), and high-performance liquid chromatography (HPLC). Selective sorption of chlorophyll a requires a minimum of 3 g of IONPs per 12 mg of chlorophyll a, with acetone as the solvent, and is dependent on a storage time of 48 h. Extended contact time of IONPs with the acetone extract, i.e., 72 h, ensures the elimination of remaining components except lutein, with a spectral purity of 98%, recovered with over 90% efficiency. The mechanism of chlorophyll removal using IONPs relies on the interaction of the pigment’s carbonyl (C=O) groups with the adsorbent surface hydroxyl (–OH) groups. Based on molecular dynamics (MD) simulations, it has been proven that the selective adsorption of pigments is also influenced by more favorable dispersion interactions between acetone and chlorophyll in comparison with other solutes. An aqueous environment significantly promotes the removal of pigments; however, it results in a complete loss of selectivity. Full article

Columnar apple was an important germplasm resource to develop compact cultivars for labor-saving cultivation and to study fruit tree architecture. MdCoL is a strong candidate gene for controlling the columnar phenotype in apple. In this study, a 2000 bp upstream region of MdCoL was cloned as a full-length promoter, named MdCoLp1. To gain a better understanding of the characterization of the MdCoL promoter, cis-acting elements and the binding sites of transcription factors were predicted and analyzed, and four binary expression vectors consisting of the GUS reporter gene under the control of the MdCoL promoter was transformed into Arabidopsis thaliana to analyze the response to abscisic acid (ABA), brassinosteroid (BR) and gibberellic acid (GA₃) of MdCoL promoters. Multiple transcription factors involving TCP, BEL1 and BES1/BZR1 and other transcription factor (TF) binding sites were predicted on the promoter of MdCoL. Histochemical staining showed that both full-length and 5′ truncated promoters could initiate GUS expression. The GUS activity was the most in leaf and stem, and mainly concentrated in the fibrovascular tissue, followed by root, and the least activity was observed in silique and flower. In addition, MdCoL expression was mainly localized in the quiescent center (QC) and lateral root growing point of root tip and the vascular tissue of stem and leaf by in situ hybridization. The results of exogenous hormones treatment showed that ABA and BR could activate the activity of the MdCoL promoter, while GA₃ had opposite effects. In columnar apple seedlings, ABA treatment could upregulate the expression of MdCoL, but GA₃ and BR restrained the transcription level of MdCoL. These results provide the foundation for deciphering the regulatory network of hormones affecting MdCoL transcription. Full article