Identification of four novel small non-coding RNAs from Xanthomonas campestris pathovar campestris.
BACKGROUND
In bacteria, small non-coding RNAs (sRNAs) have been recognized as important regulators of various cellular processes. Approximately 200 bacterial sRNAs in total have been reported. However, very few sRNAs have been identified from phytopathogenic bacteria.


RESULTS
Xanthomons campestris pathovar campestris (Xcc) is the causal agent of black rot disease of cruciferous crops. In this study, a cDNA library was constructed from the low-molecular weight RNA isolated from the Xcc strain 8004 grown to exponential phase in the minimal medium XVM2. Seven sRNA candidates were obtained by sequencing screen of 2,500 clones from the library and four of them were confirmed to be sRNAs by Northern hybridization, which were named sRNA-Xcc1, sRNA-Xcc2, sRNA-Xcc3, and sRNA-Xcc4. The transcription start and stop sites of these sRNAs were further determined. BLAST analysis revealed that the four sRNAs are novel. Bioinformatics prediction showed that a large number of genes with various known or unknown functions in Xcc 8004 are potential targets of sRNA-Xcc1, sRNA-Xcc3 and sRNA-Xcc4. In contrast, only a few genes were predicted to be potential targets of sRNA-Xcc2.


CONCLUSIONS
We have identified four novel sRNAs from Xcc by a large-scale screen. Bioinformatics analysis suggests that they may perform various functions. This work provides the first step toward understanding the role of sRNAs in the molecular mechanisms of Xanthomonas campestris pathogenesis.
Jiang
Rui-Ping
RP
Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization, Guangxi University, 100 Daxue Road, Nanning, Guangxi 530004, China.
Tang
Dong-Jie
DJ
Chen
Xiao-Lin
XL
He
Yong-Qiang
YQ
Feng
Jia-Xun
JX
Jiang
Bo-Le
BL
Lu
Guang-Tao
GT
Lin
Min
M
Tang
Ji-Liang
JL
D015152:Blotting, Northern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D008970:Molecular Weight; D012329:RNA, Bacterial / Q000737:chemistry / Q000235:genetics; D022661:RNA, Untranslated / Q000737:chemistry / Q000235:genetics*; D016959:Xanthomonas campestris / Q000235:genetics*
D018076:DNA, Complementary; D012329:RNA, Bacterial; D022661:RNA, Untranslated