ABSTRACT
'Zhizhang Guhong Chongcui' is a new cultivar of Prunus mume with cross-cultivar group characteristics. It has typical characteristics of cinnabar purple cultivar group and green calyx cultivar group. It has green calyx, white flower, and light purple xylem, but the mechanism remains unclear. In order to clarify the causes of its cross-cultivar group traits, the color phenotype, anthocyanin content and the expression levels of genes related to anthocyanin synthesis pathway of 'Zhizhang Guhong Chongcui', 'Yuxi Zhusha' and 'Yuxi Bian Lü'e' were determined. It was found that the red degree of petals, sepals and fresh xylem in branches was positively correlated with the total anthocyanin content. MYBɑ1, MYB1, and bHLH3 were the key transcription factor genes that affected the redness of the three cultivars of flowers and xylem. The transcription factors further promoted the high expression of structural genes F3'H, DFR, ANS and UFGT, thereby promoting the production of red traits. Combined with phenotype, anthocyanin content and qRT-PCR results, it was speculated that the white color of petals of 'Zhizhang Guhong Chongcui' were derived from the high expression of FLS, F3'5'H, LAR and ANR genes in other branches of cyanidin synthesis pathway, and the low expression of GST gene. The green color of sepals might be originated from the relatively low expression of F3'H, DFR and ANS genes. The red color of xylem might be derived from the high expression of ANS and UFGT genes. This study made a preliminary explanation for the characteristics of the cross-cultivar group of 'Zhizhang Guhong Chongcui', and provided a reference for molecular breeding of flower color and xylem color of Prunus mume.
Subject(s)
Animals , Anthocyanins , DNA Shuffling , Flowers/genetics , Porifera , Prunus/genetics , Glutamine/analogs & derivatives , Plant ExtractsABSTRACT
Objective:To investigate the expression levels and internal relations of matrix metalloproteinase-9(MMP-9), interleukin(IL)-1β and tissue inhibitor of metalloproteinase-1(TIMP-1) within 24 h after cerebral hypoxia and ischemia(HI) in neonatal rats.Methods:SD rats aged 7 days were randomly divided into HI group( n=40), and sham operation group(sham group, n=40). The HI models were established and divided into 5 subgroups with those at 8 cases in each group at 5 postoperative time points(0, 4, 8, 12, 24 h). Pathological changes of cerebral cortex were observed by HE staining, and the expressions of MMP-9, IL-1β and TIMP-1 were detected by Western blot and RT-PCR.In addition, the hypoxia models of mouse hippocampal neuron HT22 cells were established.With adding MMP-9 inhibitor and MMP-9 agonist, the relations among MMP-9, IL-1β and TIMP-1 were further confirmed. Results:Slight nuclear abnormalities and cell body swelling occurred in cerebral cortex at 4 h after HI, and neuronal eosinophilic changes were most obvious at 12 h. Compared with those at 8 h and 12 h, the expressions of MMP-9 and IL-1β at protein and mRNA level significantly increased at 24 h after HI( P<0.01). While MMP-9 inhibitor was added to HT22 cells under hypoxia at 4 h, IL-1β mRNA expression was down-regulated. Conclusion:In the early stage of hypoxic ischemic encephalopathy in newborn rats, the expressions of MMP-9 and TIMP-1 are time-dependent.Inhibition of MMP-9 expression could reduce the level of Interleukin-1β.