Table 3.
Relative mRNA levels of representative defense- and stress-responsive genes that are two-fold up-regulated in sugarcane after treatment with the pathogen Sorghum mosaic virus (SrMV) or the stress-regulated hormones, salicylic acid (SA) and methyl jasmonate (MeJA), as detected by microarray and qRT-PCR analyses.
| Fold induction or repression | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Putative function | Accession no. | Stem/Leaf | SrMV | SA (h) | MeJA (h) | ||||||
| Microarray | qRT-PCR | Microarray | qRT-PCR | ||||||||
| 24 | 48 | 24 | 48 | 24 | 48 | 24 | 48 | ||||
| (1) Genes coding for antimicrobial proteins | |||||||||||
| Chitinase | AW746272 | 1.48 | 0.98 | 1.2 | 9.28 | 1.82 | 12.36 | 1.27 | 0.31 | 1.87 | 1.56 |
| (2) Genes coding for proteins involved in secondary metabolism | |||||||||||
| O -methyltransferase | NM_001155649 | 3.2 | 1.03 | 0.67 | 2 | 1.01 | 3.52 | 3.99 | 2.53 | 2.53 | 0.3 |
| Dirigent-SoDIR1 | AY421731 | ||||||||||
| DIR1 | 2.4 | 1.1 | 1.23 | 17.21 | 1.84 | 32.41 | 1.68 | 0.62 | 1.99 | 1.18 | |
| DIR3 | 2.54 | 1.02 | 1.24 | 9.09 | 1.79 | 14.05 | 2.25 | 0.34 | 4.26 | 1.75 | |
| DIR8 | 2.18 | 0.98 | 0.99 | 5.27 | 1.89 | 8.89 | 1.75 | 0.64 | 1.96 | 1.61 | |
| DIR9 | 2.3 | 1.11 | 1.42 | 1.02 | 1.97 | 1.97 | 3.05 | 0.79 | 7.98 | 1.79 | |
| DIR10 | 3.58 | 0.96 | 1.43 | 21.66 | 2.56 | 30.33 | 2.17 | 0.29 | 3.65 | 0.97 | |
| DIR27 | 2.62 | 1.1 | 0.97 | 6.93 | 1.75 | 10.06 | 1.42 | 0.54 | 1.98 | 1.36 | |
| DIR32 | 2.96 | 1.03 | 1.16 | 7.73 | 1.99 | 11.04 | 1.14 | 0.43 | 1.96 | 1.06 | |
| DIR34 | 2.3 | 1.04 | 1.4 | 0.7 | 1.88 | 1.09 | 3.08 | 1.06 | 6.27 | 1.97 | |
| DIR44 | 7.84 | 0.89 | 1.24 | 19.22 | 1.94 | 29.18 | 4 | 0.79 | 9.03 | 1.74 | |
| Dirigent-SoDIR2 | AJ626722 | ||||||||||
| DIR11 | 4.83 | 0.91 | 1.33 | 20.96 | 1.08 | 5.3 | 6.45 | 1.98 | 7.21 | 2.23 | |
| DIR37 | 2.62 | 1.01 | 1.04 | 11.32 | 2.12 | 19.24 | 1.32 | 0.35 | 1.98 | 0.88 | |
| Dirigent-like | AY781903 | ||||||||||
| DIR12 | 3.97 | 0.99 | 1.01 | 15.81 | 1.97 | 26.09 | 3.16 | 0.2 | 6.04 | 1.45 | |
| DIR13 | 3.25 | 1.13 | 1.25 | 18.19 | 2.02 | 30.56 | 2.25 | 0.24 | 5.12 | 1.87 | |
| DIR16 | 3.08 | 0.94 | 1.01 | 19.64 | 2.02 | 19.86 | 8.67 | 1.16 | 9.97 | 2.99 | |
Relative abundance of mRNA transcripts of the cDNAs was determined in sugarcane stem, leaf, and root as well as in stem of plants infected with SrMV or treated with SA or MeJA. Values of each transcript were normalized to that of the sugarcane constitutive ubiquitin gene. Values represent the average normalized ratios of transcripts obtained: (1) from stems to those obtained from leaves, and (2) from stems at the indicated time of treatment to those obtained from the untreated (0 time or no infection). Data are representative of two biological samples and three technical repetitions. Values for cDNAs that are two-fold up-regulated are in bold.