[Effects of crude toxin from Alternaria alternata on the growth and physiological metabolism of chrysanthemum 'Jinba' seedlings]. / é“¾æ ¼å­¢èŒç²—æ¯’ç´ å¯¹èŠèŠ±'神马'幼苗生长及生理代谢的影响.

The chrysanthemum black spot caused by Alternaria alternata significantly reduced the quality and yield of chrysanthemum. The crude toxin secreted by A. alternata in the metabolic process have elopathic effects on plants, which is the main pathogenic factor for the occurrence of chrysanthemum black spot. The pathogenic fungi A. alternate was isolated from chrysanthemum black spot leaves, The effects of crude toxin on plant height, stem diameter, root length, resistant material content, membrane relative permeability, polyphenol oxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL) in different treatments of chrysanthemum 'Jinba' seedlings were investigated. The results showed that the crude toxin of A. alternata had an inhibition effect on plant height, stem diameter and root length. The toxin concentration was positively correlated with the inhibitory effect. 14 days after crude toxin treatment, plant height, stem diameter and root length were significantly inhibited, with an reduction of 28.9%, 21.4% and 23.3%, respectively. The cell membrane permeability of leaf increased with the toxin concentration. Under the same toxin concentration, the cell membrane permeability first increased and then decreased with the treatment duration. The contents of soluble protein, malondialdehyde (MDA) and proline in leaves were significantly increased after treatment with the toxin solution. The increases of PAL, POD and PPO were the most significant in 10 times A. alternatacrude toxin treatment. The pathogenicity of A. alternate crude toxin to the chrysanthemum 'Jinba' seedlings was mainly through inhibi-ting the normal growth of roots and stems, destructing the root cell membrane permeability and increasing the contents of MDA, normal soluble sugar and proline, and promoting the activities of PAL, POD, PPO in leaf tissues.

Identification of PA28ß as a potential novel biomarker in human esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is one of the most common and serious malignancies in China. However, the exact mechanisms of tumor formation and progression are unclear. As late diagnosis and poor therapeutic efficacy result in lower survival rates, identifying biomarkers for early detection, prognostic evaluation, and recurrence monitoring of ESCC is necessary. Here we analyzed 10 protein expression profiles of ESCC core tissues and paired normal esophageal epithelial tissues using two-dimensional gel electrophoresis. We excised 29 protein spots with two-fold or greater differential expression between cancer and normal tissues and identified them using matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight mass spectrometry. The role of PA28ß in ESCC cell was confirmed using cell growth, colony formation and soft agar in TE-1 cells pre- and post- PA28ß transfection. Compared to their expression in the adjacent normal epithelia, 12 proteins, including transgelin (TAGLN), were upregulated in ESCC tissues; 17 proteins, including proteasome activator 28-beta subunit (PA28ß), were downregulated (p < 0.05). Western blotting and immunohistochemistry confirmed that PA28ß was significantly underexpressed in ESCC tissues. The functional assays demonstrate that PA28ß inhibited cell growth, proliferation and malignancy of TE-1 cells. Among the differentially expressed proteins, PA28ß is a potential tumor inhibitor.