Transcriptome Analysis of Apples in High-Temperature Treatments Reveals a Role of MdLBD37 in the Inhibition of Anthocyanin Accumulation.

Coloring in apple fruit due to anthocyanin accumulation is inhibited by high temperature; however, the underlying mechanism remains unclear. In the present study, total anthocyanin and cyanidin 3-galactoside contents were determined and compared between cv. 'Redchief Delicious' apple fruits at 25 °C and 35 °C treatments. The high temperature (35 °C) treatment substantially decreased total anthocyanin and cyanidin 3-galactoside contents. The transcriptomes of 25 °C- and 35 °C-treated apples were analyzed by high-throughput RNA sequencing. A total of 8354 differentially expressed genes (DEGs) were detected at four time points corresponding to the two temperature treatments. The up-regulated DEGs were annotated using GO as well as KEGG databases. A network module of 528 genes (including 21 transcription factors) most associated with the total anthocyanin and cyanidin 3-galactoside contents was constructed by weighted correlation network analysis (WGCNA). In the WGCNA module, we unearthed a LOB domain-containing gene designated as MdLBD37. The expression of MdLBD37 was sharply up-regulated by high temperature and negatively correlated with the total anthocyanin and cyanidin 3-galactoside contents. Overexpression of MdLBD37 in apple fruit and calli decreased the expression of anthocyanin biosynthetic genes, such as MdCHI, MdCHS, MdF3H, MdANS, MdDFR, and MdUFGT, along with anthocyanin accumulation. Our results suggested that MdLBD37 significantly influenced the high-temperature inhibition of anthocyanin accumulation in apples. The findings shed more light on the mechanism of anthocyanin inhibition during high-temperature stress in apples.

[Exploration of the correlation between Chinese medicine syndrome types of verrucous gastritis and the pressions of gastric mucosal hypoxia-inducible factor-1alpha as well as downstream molecules].

OBJECTIVE: To study the expressions changes of gastric mucosal hypoxia-inducible factor-1alpha (HIF-1alpha) and downstream molecules [such as vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2)] of verrucous gastritis (VG) patients of different Chinese medicine (CM) syndrome types and their clinical significance. METHODS: Totally 94 VG patients were assigned to Gan-Wei disharmony group (GWDG, 28 cases), the damp-heat in Pi-Wei group (DHPWG, 17 cases), the blood stasis in Wei-collateral group (BSWCG, 20 cases), and the insufficiency of Pi-yang group (IPYG, 29 cases). Another 30 patients with chronic mild non-active superficial gastritis patients accompanied with negative Hp infection were recruited as the control group. The Hp infection was detected using 14C-labeled urea breath test. The expressions of HIF-1alpha, VEGF, and COX-2 in the gastric mucosal tissue were detected using immunohistochemical EnVision two-step test. RESULTS: The positive Hp infection rate in VG patients was 37.23% (35/94 cases). The positive Hp infection rate in patients of DHPWG (76. 47%) was significantly higher than the other three groups (32.14% in GWDG, 31.03% in IPYG, and 20.00% in BSWCG, P < 0.01). The expressions of HIF-1alpha and COX-2 in VG patients of different syndrome types were obviously higher than those of the control group (P < 0.01, P < 0.05). Of them, the expression of HIF-1alpha was the highest in BSWCG and the expression of COX-2 was the highest in DHPWG. The expression of VEGF was higher in DHPWG and IPYG than in the control group and the GWDG (P < 0.01, P < 0.05). CONCLUSIONS: The expressions of HIF-1alpha, VEGF, COX-2, and Hp infection showed certain changes in VG patients of different syndrome types. The expression of HIF-1alpha was the strongest in BSWCG. The expressions of VEGF and COX-2 as well as Hp infection were the highest in DHPWG. All showed the specificity of CM syndromes.