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Background The NAC (NAM, ATAF1/2 and CUC2) domain protein plays an important role in plant growth and development. The function of members of NAC gene family has been deeply studied in many plants. However, the evolutionary relationships and characteristics of NAC family genes in Dendrobium catenatum (D.candidum) unclear. Results In this study, we identified 33 NAC genes in D.catenatum, all contain NAM conservative domain. Subcellular localization predictions indicated that all the DcNAC proteins are localized to the nucleus. Phylogenetic analysis suggested that the DcNAC gene family could be divided into four groups. Then, the amino-acid composition, physicochemical properties, gene structure, motif, and promoter cis-acting elements were analyzed, the evolutionarily conservative gene DcNAC043 was found. Using qRT-PCR, DcNAC043 was proved to respond to drought stress induction in D.catenatum. At the same time, phloroglucinol staining proved that the expression of DcNAC043 in the plant was up-regulated, which could increase the lignin content in the plant. Conclusions We identified 33 NAC genes in D.catenatum, which supplemented the relevant information of NAC gene family in D.catenatum. At the same time, the gene function of DcNAC043 and its contribution to the response of Dendrobium to drought stress were verified. These results provide a comprehensive evolutionary history of NAC genes in D.catenatum, and insight into the biological functions of DcNAC043 genes in response to drought stress.

Additional file 1: Table S1. Polymorphic residues in the E protein among Chongming Tembusu virus strains, FX2010 strain, and the live attenuated vaccine strain FX2010-180P derived from FX2010. Table S2. Seroprevalence of Tembusu virus antibodies in different poultries and directions in Chongming Island in 2021.

Bone regeneration is a coordinated process involving connections between blood vessels and osteocytes. Angiogenesis and osteogenesis are tightly connected throughout the progression of bone regeneration. This study aimed to explore the underlying mechanism of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)-regulated angiogenesis during bone regeneration. Gene and protein expression was detected by quantitative real-time PCR and western blot assay. Vascular endothelial growth factor (VEGFA) secretion was assessed by enzyme-linked immunosorbent assay. To evaluate the effect of osteogenic differentiation, alkaline phosphatase (ALP) and alizarin red staining assays were performed. Proliferation was detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Migration and angiogenesis were measured using Transwell and tube formation assays. A dual luciferase reporter assay was performed to confirm the binding relationship among MALAT1, miR-494, and specificity protein 1 (SP1). Expression levels of MALAT1, SP1, and VEGFA were elevated and miR-494 was suppressed in MC3T3-E1 cells after culture in osteogenic medium. MALAT1 knockdown suppressed the osteogenic differentiation of MC3T3-E1, since ALP activity, mineralized nodules, and expression of the osteodifferentiated markers runt-related transcription factor 2 and osterix were restrained. In addition, MALAT1 silencing inhibited angiogenesis during bone regeneration, as the proliferation, migration, and capillary tube formation of human umbilical vein endothelial cells were blocked. Furthermore, miR-494 was directly targeted by MALAT1 and regulated the SP1/Toll-like receptor 2 (TLR2)/bone morphogenetic protein 2 (BMP2) axis by targeting SP1. Furthermore, miR-494 overexpression inhibited angiogenesis and osteogenic differentiation. Moreover, SP1 overexpression or miR-494 inhibition rescued the regulatory effect of sh-MALAT1 on angiogenesis and osteogenic differentiation. Taken together, these findings indicate that MALAT1 promotes angiogenesis and osteogenic differentiation by targeting miR-494 and activating the SP1/TLR2/BMP2 pathway, suggesting a novel target for bone regeneration therapy by promoting angiogenesis.

Driven by the massive demand in recent years, the production of β-alanine has significantly progressed in chemical and biological ways. Although the chemical method is relatively mature compared to biological synthesis, its high cost of waste disposal and environmental pollution does not meet the environmental protection standard. Hence, the biological method has become more prevalent as a potential alternative to the chemical synthesis of β-alanine in recent years. As a result, the aspartate pathway from L-aspartate to β-alanine (the most significant rate-limiting step in the β-alanine synthesis) catalyzed by L-aspartate-α-decarboxylase (ADC) has become a research hotspot in recent years. Therefore, it is vital to comprehensively understand the different enzymes that possess a similar catalytic ability to ADC. This review will investigate the exploratory process of unique synthesis features and catalytic properties of ADC/ADC-like enzymes in particular creatures with similar catalytic capacity or high sequence homology. At the same time, we will discuss the different β-alanine production methods which can apply to future industrialization.

The novel amphiphilic acylated dextran-g-polyisobutylene (AcyDex-g-PIB) graft copolymers with different branch lengths (Mn,PIB, 2600–5800 g/mol) and grafting numbers (GN, 5–28 per 1000 Dex monosaccharide) were successfully synthesized via the nucleophilic substitution of the hydroxyl (―OH) side groups along AcyDex backbone by the living PIB-THF4+ chains prepared through cationic polymerization. The crystallization of AcyDex backbone in AcyDex-g-PIB graft copolymers was confined due to the presence of PIB branches and the morphology changed from short rod-like crystals to fragment-like crystals with increasing Mn,PIB and GN. The obvious microphase separation occurred due to the incompatibility between hard AcyDex backbone and soft PIB branches. AcyDex-g-PIB graft copolymers exhibit excellent biocompatibility towards HeLa cells and good hemocompatibility with red blood cells (RBCs), both of which increase with increasing GN. The increases of water contact angle and roughness on the surface of the graft copolymers with increasing Mn,PIB and GN manifest the anti-protein adsorption performance. The amphiphilic AcyDex-g-PIB graft copolymers could self-assemble in aqueous solution into nanospheres, which can be used as pH-sensitive drug carriers and can release 100% of the loaded drug within 72 h at pH=7.4. AcyDex-g-PIB graft copolymers bearing silver nanoparticles (Ag-NPs, 0.8 wt%–3.9 wt%, 4.5–9.5 nm) show good antibacterial properties. This kind of amphiphilic graft copolymer would have a promising prospect in biological and medical fields.