Programmed cell death in Laminaria japonica(Phaeophyta) tissues infected with alginic acid decomposing bacterium  

作　　者：WANGGaoge LINWei ZHANGLijing YANXiaojun DUANDelin 

机构地区：[1]InstituteofOceanology,ChineseAcademyofSciences,Qingdao266071,China [2]YellowSeaFisheriesResearchInstitute,ChineseAcademyofFisherySciences,Qingdao266071,China

出　　处：《Progress in Natural Science:Materials International》2004年第12期1064-1068,i009,共6页自然科学进展·国际材料（英文版）

基　　金：SupportedbytheMajorStateBasicResearchDevelopmentProgramofChina(GrantNo.G1999012004)andShangdongScienceandTechonologyCommittee(GrantNo.20032418)

摘　　要：TdT mediated dUTP biotin nick end labeling (TUNEL) is a sensitive and valid method for detecting DNA cleavage in programmed cell death (PCD). Using this method, DNA cleavage was observed in Laminaria japonica sporophytic tissues, which were infected with alginic acid decomposing bacterium. It was found that DNA cleavage occurred 5 min after the infection, the fragments with 3′ OH groups of cleaved nuclear DNA increased with time of infection and spread from the infection site. Although no typical DNA ladder (200 bp/180 bp) was detected by routine agarose gel electrophoresis, the cleavage of nuclear DNA fragments of 97～48.5 kb could be detected by pulsed field gel electrophoresis (PFGE). By using CaspGLOW TM fluorescein active caspase 3 staining method, caspase 3 activity has been detected in response to the infection of alginic acid decomposing bacterium. Our results are similar to the observations in hypersensitive response (HR) of higher plant, suggesting that the rapid cell death of L. japonica infected by alginic acid decomposing bacterium might be involved in PCD, and indicating that the occurrence of PCD is an active defense process against the pathogen’s infection.TdT mediated dUTP biotin nick end labeling (TUNEL) is a sensitive and valid method for detecting DNA cleavage in programmed cell death (PCD). Using this method, DNA cleavage was observed in Laminaria japonica sporophytic tissues, which were infected with alginic acid decomposing bacterium. It was found that DNA cleavage occurred 5 min after the infection, the fragments with 3′ OH groups of cleaved nuclear DNA increased with time of infection and spread from the infection site. Although no typical DNA ladder (200 bp/180 bp) was detected by routine agarose gel electrophoresis, the cleavage of nuclear DNA fragments of 97～48.5 kb could be detected by pulsed field gel electrophoresis (PFGE). By using CaspGLOW TM fluorescein active caspase 3 staining method, caspase 3 activity has been detected in response to the infection of alginic acid decomposing bacterium. Our results are similar to the observations in hypersensitive response (HR) of higher plant, suggesting that the rapid cell death of L. japonica infected by alginic acid decomposing bacterium might be involved in PCD, and indicating that the occurrence of PCD is an active defense process against the pathogen's infection.

关 键 词：alginic acid decomposing bacterium caspase-3 Laminaria japonica hypersensitive reaction (HR) programmed cell death (PCD) TUNEL. 

分 类 号：Q949.28[生物学—植物学] Q942