Carbon catabolite repressor gene BbCre1 influences carbon source uptake but does not have a big impact on virulence in Beauveria bassiana.
A gene (BbCre1, GenBank accession number EF108309) encoding a carbon catabolite repressor (CreA) with two Cys(2)His(2) zinc finger regions and a nuclear localization signal was cloned from the entomopathogenic fungus Beauveria bassiana. Overexpression and antisense strategies were used to investigate the biological functions of this gene. Compared with the wild type, the conidial yield and colony growth of BbCre1-overexpression transformants were significantly decreased on the plates with xylose or ethanol as the sole carbon source. With glucose as the sole carbon source, a significant difference was observed in the activity of Pr1A-like protease among BbCre1-overexpression transformants, antisense-BbCre1 transformants and the wild type. However, bioassays showed that knockdown or overexpression of BbCre1 did not have a significant impact on the virulence of B. bassiana to aphids. These results imply that the fungus remains virulent, even when simpler, less expensive nutrients are available, i.e. glucose.
Key Laboratory of Biotechnology and Crop Quality Improvement of Ministry of Agriculture of China, Biotechnology Research Center, Southwest University, Chongqing 400716, PR China.
Kai
K
Jin
Zhibing
Z
Luo
Xiaodong
X
Jiang
Yongjun
Y
Zhang
Yonghong
Y
Zhou
Yan
Y
Pei
D000818:Animals; D001042:Aphids / Q000382:microbiology; D052982:Beauveria / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D002244:Carbon / Q000378:metabolism*; D057465:Catabolite Repression / Q000235:genetics; D003001:Cloning, Molecular; D000431:Ethanol / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000502:physiology; D005947:Glucose / Q000378:metabolism; D008969:Molecular Sequence Data; D012097:Repressor Proteins / Q000235:genetics* / Q000502:physiology; D016415:Sequence Alignment; D014774:Virulence / Q000235:genetics; D014994:Xylose / Q000378:metabolism
D005656:Fungal Proteins; D012097:Repressor Proteins; D000431:Ethanol; D002244:Carbon; D014994:Xylose; D005947:Glucose