Flavonoid compounds play important roles in the modern diet, and pear fruits are an excellent dietary source of these metabolites. However, information on the regulatory network of flavonoid biosynthesis in pear fruits is rare. In this work, 18 putative flavonoid-related MYB transcription factors (TFs) were screened by phylogenetic analysis and four of them were correlated with flavonoid biosynthesis patterns in pear fruits. Among these MYB-like genes, the specific functions of two novel MYB TFs, designated as PbMYB10b and PbMYB9, were further verified by both overexpression and RNAi transient assays. PbMYB10b, a PAP-type MYB TF with atypical motifs in its conserved region, regulated the anthocyanin and proanthocyanidin pathways by inducing the expression of PbDFR, but its function could be complemented by other MYB TFs. PbMYB9, a TT2-type MYB, not only acted as the specific activator of the proanthocyanidin pathway by activating the PbANR promoter, but also induced the synthesis of anthocyanins and flavonols by binding the PbUFGT1 promoter in pear fruits. The MYBCORE-like element has been identified in both the PbUFGT1 promoter and ANR promoters in most species, but it was not found in UFGT promoters isolated from other species. This finding was also supported by a yeast one-hybrid assay and thus enhanced the likelihood of the interaction between PbMYB9 and the PbUFGT1 promoter.

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Vascularization and bone regeneration are two closely related processes during bone reconstruction. A three-dimensional (3D) scaffold with porous architecture provides a suitable microenvironment for vascular growth and bone formation. Here, we present a simple and general strategy to construct a nanofibrous poly( l -lactide)/poly(ε-caprolactone) (PLLA/PCL) scaffold with interconnected perfusable microchannel networks (IPMs) based on 3D printing technology by combining the phase separation and sacrificial template methods. The regular and customizable microchannel patterns within the scaffolds (spacings: 0.4 mm, 0.5 mm, and 0.6 mm; diameters: 0.8 mm, 1 mm, and 1.2 mm) were made to investigate the effect of microchannel structure on angiogenesis and osteogenesis. The results of subcutaneous embedding experiment showed that 0.5/0.8-IPMs (spacing/diameter = 0.5/0.8) and 0.5/1-IPMs (spacing/diameter = 0.5/1) scaffolds exhibited more vascular network formation as compared with other counterparts. After loading with vascular endothelial growth factor (VEGF), VEGF@IPMs-0.5/0.8 scaffold prompted better human umbilical vein endothelial cells (HUVECs) migration and neo-blood vessel formation, as determined by Transwell migration, scratch wound healing, and chorioallantoic membrane (CAM) assays. Furthermore, the microangiography and rat cranial bone defects experiments demonstrated that VEGF@IPMs-0.5/0.8 scaffold exhibited better performance in vascular network formation and new bone formation compared to VEGF@IPMs-0.5/1 scaffold. In summary, our results suggested that the microchannel structure within the scaffolds could be tailored by an adjustable caramel-based template strategy, and the combination of interconnected perfusion microchannel networks and angiogenic factors could significantly enhance vascularization and bone regeneration.

Three-dimensional (3D) printed scaffolds provide promising perspective in bone tissue engineering. 3D printed scaffolds with micro- and nano-fibrous structure that facilitates the cell adhesion and migration, and combined vascularization and...

Black carrots are characterized by a significant amount of anthocyanins, which are not only a good source of natural food colorant, but can also provide many health benefits to humans. In the present work, taproots of different carrot genotypes were used to identify the candidate genes related to anthocyanin synthesis, with particular a focus on R2R3MYB, bHLH transcription factors, and glutathione S-transferase gene (GST). The RNA-sequencing analysis (RNA-Seq) showed that DcMYB6 and DcMYB7 had a genotypic dependent expression and they are likely involved in the regulation of anthocyanin biosynthesis. They were specifically upregulated in solid black taproots, including both black phloem and xylem. DcbHLH3 (LOC108204485) was upregulated in all black samples compared with the orange ones. We also found that GST1 (LOC108205254) might be an important anthocyanin transporter, and its upregulated expression resulted in the increasing of vacuolar anthocyanin accumulation in black samples. Moreover, high performance liquid chromatographic (HPLC) analysis and liquid chromatography coupled to mass spectrometry (LC-MS) were used to identify the individual anthocyanin in the purple tissues of two carrot cultivars. The results showed that five main anthocyanin compounds and the most abundant anthocyanin were the same in different tissues, while the second-highest anthocyanin between three tissues was different, even in the same cultivar. In conclusion, this study combined anthocyanin profiles and comparative transcriptomic analysis to identify candidate genes involved in anthocyanin biosynthesis in carrots, thus providing a better foundation for improving anthocyanin accumulation in carrots as a source of colorants.

A new type of amphiphilic pillar[5]arene with excellent surface activity was designed and synthesized successfully. Interestingly, this pillar[5]arene shows controllable self-assembly behaviour in water and can be applied in white-light-emitting systems.

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The adrenal gland protein AD-004 like protein (ADLP) from Caenorhabditis elegans was cloned and expressed in Escherichia coli. Enzyme assays showed that ADLP has special adenylate kinase (AK) properties, with ATP and dATP as the preferred phosphate donors. In contrast to all other AK isoforms, AMP and dAMP were the preferred substrates of ADLP; CMP, TMP and shikimate acid were also good substrates. Subcellular localization studies showed a predominant nuclear localization for this protein, which is different from AK1-AK5, but similar to that of human AK6. These results suggest that ADLP is more likely a member of the AK6 family. Furthermore, RNAi experiments targeting ADLP were conducted and showed that RNAi treatment resulted in the suppression of worm growth.