49种山茶在低温和盐胁迫下的双抗能力分析

根据杜鹃红山茶(Camellia azalea)抗坏血酸过氧化物酶(ascorbate peroxidase,APX)基因(CaAPX1,GenBank登录号:KP635267)序列,设计实时荧光定量PCR引物,并对4℃低温和200 mg·L~(-1)NaCl胁迫下杜鹃红山茶CaAPX1表达量进行分析,发现该基因能够在低温和NaCl胁迫下应激上调表达。实时荧光定量PCR分析发现,CaAPX1在49个山茶品种中均得到表达,但表达量有差异。通过田间抗寒耐盐指数和APX1表达量隶属函数值对49个山茶品种抗寒和耐盐双抗能力进行分析,其中Ⅰ类抗寒和耐盐能力强的有4个品种,Ⅱ类抗寒和耐盐能力中等的有11个品种,Ⅲ类抗寒和耐盐能力弱的有34个品种。

Analysis of Potential Double Resistances for 49 Camellia Cultivars Under Low Temperature and Salt Stress

AIM:To explore the expression level of interleukin-1 receptor-associated kinase-1 (IRAK-1) and the secretion function of pulmonary artery smooth muscle cells (PASMCs) in chronic obstructive pulmonary disease (COPD) rats.METHODS:A rat model of COPD was established. Image analysis was used to calculate the ratio of thickness to outside diameter of pulmonary arterioles (WT%) and the ratio of vessel wall area to total vessel area (WA%). The PASMCs from COPD rats were digested, isolated and purified, and the cells were randomly divided into control group, lipopolysaccharide (LPS) group, IRAK-1/4 inhibitor group and LPS + IRAK-1/4 inhibitor group. The protein levels of p-IRAK-1 and IRAK-1 were determined by Western blot. The levels of platelet-derived growth factor-AB (PDGF-AB) and interleukin-6 (IL-6) in the culture supernatant of PASMCs in each group were measured by ELISA. The correlation between p-IRAK-1 level and the concentrations of the secretion factors in the PASMCs was analyzed. RESULTS:The WT% and WA% in COPD model group were higher than those in control group (P<0.01). Under the optical microscope, the PASMCs showed in spindle in shape, and their α-smooth muscle actin was stained red under fluorescence microscope. Compared with control group, LPS up-regulated the protein level of phosphorylated IRAK-1 (p-IRAK-1) and the levels of PDGF-AB and IL-6 (P<0.05). IRAK-1/4 inhibitor was capable of suppressing the effects of LPS (P<0.05). The protein level of p-IRAK-1 was positively correlated with the concentrations of PDGF-AB and IL-6 in the PASMCs. CONCLUSION:IRAK-1 participates in the regulation of PASMCs to secrete PDGF-AB and IL-6, which provided a new target for the early intervention of COPD.