Table 5.
Potential reference gene combinations (and number of genes involved in each comparison) used in gene expression normalization of glutamine-dependent asparagine synthetase (AS), with cDNAs of sugarcane accessions (root under drought stress, 24 h of continuous dehydration).
| Comparison | Gene combinations | Number of genes | Expression* value | P value | Regulation |
|---|---|---|---|---|---|
| 1 | αTUB, H1, and SAMDC | 3 | 1.431 | 0.112 | ns |
| 2 | GAPDH, 25S rRNA, and SAMDC | 3 | 1.482 | 0.009 | ns |
| 3 | αTUB, H1, GAPDH, 25S rRNA, and SAMDC | 5 | 1.496 | 0.113 | ns |
| 4 | αTUB, H1, UBQ, and SAMDC | 4 | 1.557 | 0.105 | ns |
| 5 | UBQ and SAMDC | 2 | 1.595 | 0.305 | ns |
| 6 | αTUB and H1 | 2 | 1.519 | 0.000 | UR |
| 7 | GAPDH and 25S rRNA | 2 | 1.600 | 0.017 | UR |
| 8 | αTUB, H1, GAPDH, and 25S rRNA | 4 | 1.559 | 0.011 | UR |
| 9 | αTUB, H1, and UBQ | 3 | 1.667 | 0.033 | UR |
| 10 | GAPDH, 25S rRNA, and UBQ | 3 | 1.725 | 0.017 | UR |
| 11 | αTUB, H1, GAPDH, 25S rRNA, and UBQ | 5 | 1.640 | 0.017 | UR |
*REST software analysis after the ΔΔCq method. UR: upregulated; ns: not significant at P < 0.05; αTUB: alpha-tubulin; H1: histone H1; SAMDC: S-adenosylmethionine decarboxylase; GAPDH: glyceraldehyde 3 phosphate dehydrogenase; 25S rRNA: 25S ribosomal RNA; UBQ: ubiquitin.