Transcription profiling of soybean nodulation by Bradyrhizobium japonicum.
Legumes interact with nodulating bacteria that convert atmospheric nitrogen into ammonia for plant use. This nitrogen fixation takes place within root nodules that form after infection of root hairs by compatible rhizobia. Using cDNA microarrays, we monitored gene expression in soybean (Glycine max) inoculated with the nodulating bacterium Bradyrhizobium japonicum 4, 8, and 16 days after inoculation, timepoints that coincide with nodule development and the onset of nitrogen fixation. This experiment identified several thousand genes that were differentially expressed in response to B. japonicum inoculation. Expression of 27 genes was analyzed by quantitative reverse transcriptase-polymerase chain reaction, and their expression patterns mimicked the microarray results, confirming integrity of analyses. The microarray results suggest that B. japonicum reduces plant defense responses during nodule development. In addition, the data revealed a high level of regulatory complexity (transcriptional, post-transcriptional, translational, post-translational) that is likely essential for development of the symbiosis and adjustment to an altered nutritional status.
Brechenmacher
Laurent
L
National Center for Soybean Biotechnology, Divisions of Plant Sciences and Biochemistry, University of Missouri, Columbia, MO 65211, USA.
Kim
Moon-Young
MY
Benitez
Marisol
M
Li
Min
M
Joshi
Trupti
T
Calla
Bernarda
B
Lee
Mei Phing
MP
Libault
Marc
M
Vodkin
Lila O
LO
Xu
Dong
D
Lee
Suk-Ha
SH
Clough
Steven J
SJ
Stacey
Gary
G
D020369:Bradyrhizobium / Q000254:growth & development*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053204:Root Nodules, Plant / Q000235:genetics* / Q000382:microbiology; D030262:Soybean Proteins / Q000235:genetics; D013025:Glycine max / Q000235:genetics* / Q000382:microbiology; D014158:Transcription, Genetic
D030262:Soybean Proteins