Exocyst subunit BcSec3 regulates growth, development and pathogenicity in Botrytis cinerea

Botrytis cinerea is a saprophytic plant pathogenic fungus that can infect a variety of crops and cause gray mold,which leads to huge losses worldwide. The role of exocyst in fungal pathogenicity is being revealed. In thisstudy, homologous recombination technology was used to knock out the exocyst subunit BcSec3 of B. cinerea,and it was found that the BcSec3 subunit plays a crucial role in the growth and pathogenicity of B. cinerea.Compared with the wild-type strain B05.10, the mycelial growth ability of the BcSec3 deletion strain wasreduced by up to 49.8%, the conidia production capacity of the deletion strain was severely lost, and nosclerotia was formed. The polygalacturonase, is one of plant cell wall hydrolases, whose activity in BcSec3deletion strain was significantly reduced. In the tomato leaves infection assay in vitro, the lesion area caused bythe BcSec3 deletion strain was only 20% of the wild type after 5 days of infection. Observation by lightmicroscope showed that the morphology of BcSec3 deletion strain mycelium was significantly changed, themycelium became thinner and deformed, and the polarity growth was not obvious. Further observation withlaser confocal microscopy and transmission electron microscopy was conducted. It was found that comparedwith the wild type, the number of vesicles in BcSec3 deleted cells reduced and localization and distribution ofvesicles changed. In mutant cell, vesicles relatively concentrated in the cytoplasm, while in wild-type cellmainly concentrated inside the cell membrane. These evidences indicate that the exocyst subunit BcSec3 playsan important role in the growth, development and pathogenicity of B. cinerea.

Growth Suppression of Human Lung Cancer Cells and Implanted Tumors by Adenovirus-mediated Transfer of the PTEN Gene / 华中科技大学学报（医学）（英德文版）

This study examined the effects of a recombinant adenovirus Ad-PTEN-EGFP on the proliferation of A549 cells,a human lung carcinoma cell line,in vitro and on the growth of the implanted tumors in the nude mice in vivo,explored the underlying mechanisms and evaluated the in vitro transfection efficiency of Ad-PTEN-EGFP into A549 cells.The expression of Ad-PTEN-EGFP in the A549 cells was determined.The proliferation and the apoptosis rates of the A549 cells with Ad-PTEN-EGFP transfection or not was detected by MTT and flow cytometry.Ad-PTEN-EGFP at different doses was injected intratumorally to the tumor-bearing mice induced by the A549 cells.Tumor sizes were measured on an altemate day.After all the mice were sacrificed,the implanted tumors were removed for routine histological examination,weight test,HE staining and immunohistochemical staining.The expressions of Bax,P16 and P53 in the tumor tissues and those of caspase-3,CD34and VEGF in the mouse sera were detected.Tumor cell apoptosis was measured by TUNEL method.The results showed that the vitality of the A549 cells after transfection with Ad-PTEN-EGFP declined.The expression of green fluorescent protein was observed under fluorescent microscope.The transfection rate was in excess of 50%.The mRNA and protein expression of PTEN in the transfected cells was confirmed.The proliferation rate of the transfected cells was significantly decreased when compared with that of the non-transfected cells(P<0.05).The number of the apoptosis cells was increased in the transfected cells(P<0.05).The models of implanted tumors were successfully established by injection of the A549 cells in the flank of Balb/c nude mice.Administration of Ad-PTEN-EGFP to the tumor-bearing nude mice resulted in a suppression of tumor growth.There were statistically significant differences in the tumor weight and tumor volume between the Ad-PTEN-EGFP-treated group and the control groups(P<0.05).In contrast to those in the control groups,tumor tissues in the Ad-PTEN-EGFP-treated group were shown to have typical extensive vacuolar degeneration and massive hemorrhagic necrosis.Apoptotic bodies were also observed in the tumor cells.The expressions of Bax,caspase-3 and P16 were increased(P<0.05)while those of CD34,VEGF and P53 decreased(P<0.05)in the Ad-PTEN-EGFP-treated group.It is concluded that Ad-PTEN-EGFP could induce the apoptosis of the A549 cells and inhibit their proliferation.And it could also substantially suppress the tumor growth in the tumor-bearing nude mice and induce apoptosis of the tumor cells as well.These findings carry significant implications for adenovirus vector-based PTEN gene therapies for lung cancers.

Correlation and Expression of COX-2 and P53 Protein in Basal Cell Carcinoma of Eyelid / 华中科技大学学报（医学）（英德文版）

.01). Spearman rank correlation analysis demonstrated a positive correlation between the expression of COX-2 and p53 (r=0.113, P=0.421). It was concluded that COX-2 can increase the expression of p53 protein, therefore suppressing apop-tosis.