Figure 1.
Structural classification of OsGH9 family in rice.
(A) Phylogenetic tree of OsGH9 family proteins: Clustal X program and tree construction using MEGA3.1 used for multiple alignment analysis of 25 rice GH9 family proteins. (B) Exon-intron comparison of OsGH9 family genes: GSDS http://gsds.cbi.pku.edu.cn/ was used for analysis of the exon-intron structures. (C) Motif distributions of OsGH9 family proteins. The 25 motifs of OsGH9 family proteins annotated in Table S8 using the interProScan search program http://www.ebi.ac.uk/Tools/InterProScan/, and then identified using the MEME program (version 4.0) http://meme.sdsc.edu/meme/cgi-bin/meme.cgi.
Figure 2.
Co-expression profiling among OsGH9 and OsCESA in rice.
The cDNA chip data of 66 tissues obtained from two rice var. ZS97 and MH63 at CREP database http://crep.ncpgr.cn/cgi/home.pI website, and the transcription profiling of OsGH9 and OsCESA family genes performed by the hierarchical cluster method.
Table 1.
Correlation coefficients between OsGH9A3/B5 and OsCESA1/3/8 in 66 rice tissues (n = 66).
Table 2.
Correlation coefficient among OsGH9B1, 2, 3 and B16 in 66 rice tissues (n = 66).
Figure 3.
Morphological observation and carbohydrate analysis of two rice mutants.
(A) Phenotypes of two rice mutants (Osfc4, Osfc11) and wild type (NPB): upper panel, rice growth at mature stage; middle panel, manual bending of mature culms; down panel, stem dissection under light microscope. (B) Cell wall composition of mutants and wild type in the mature stems: Cellulose, hemicelluloses and lignin (% DW, dry weight) contents expressed as means ± SD (n = 3). (C) Diagram of four internodes at booting stage. (D) Cellulose contents (% DW, dry weight) of four internodes as shown in (C): Data as means ± SD (n = 3).
Figure 4.
Correlation analysis among cellulase activity, lignocellulose crystallinity index and OsGH9 gene expression in four internodes of mutants (fc4 and fc11) and wild type (NPB) at booting stage.
(A) Observation of cellulase activity in situ of the 3rd internode tissues: The detection of cellulase activity in situ, and the bar indicated 50 µm. (B) Assay of in vitro cellulase specific activity (U. mg−1 protein) in four internodes tissues: Total proteins of four different internodes were used for in vitro cellulase assay by Markergene fluorescent Cellulase Assay Kit. (C) Lignocellulose crystallinity index (CrI) of four internodes tissues. (D) Correlation (n = 12) between cellulase specific activity and lignocellulose CrI among 12 internode samples of four stems in mutants (fc4 and fc11) and wild type (NPB). (E) Correlation coefficients (n = 12) between OsGH9B1, 3, and 16 transcript levels and cellulase specific activity or lignocellulose CrI.
Table 3.
Comparison of gene functional patterns in rice and Arabidopsis based on the co-expression profiling data in Figure 2 and Figure S3.