Molecular cloning and expression analysis of a RGA-like gene responsive to plant hormones in Brassica napus
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DELLA proteins are negative regulators of GA-induced growth. DELLA protein family is characterized by a DELLA domain essential for GA-dependent proteasomal degradation of DELLA repressors. A full-length cDNA encoding a putative DELLA protein with high sequence homology to Arabidopsis thaliana RGA (AtRGA), designated as BnRGA, was isolated from Brassica napus. The full-length cDNA of BnRGA contained a 1,740 bp open reading frame (ORF) encoding a precursor protein of 579 amino acid residues. Comparative and bioinformatics analyses revealed that BnRGA showed a high degree of homology with DELLA proteins and contained the DELLA domain, TVHYNP domain, VHIID domain and RVER domain. Using real-time PCR, the expression patterns of BnRGA and two our previously isolated genes, BnGID1a and BnSLY1 in B. napus, were analyzed by adding exogenous gibberellins acid-3 (GA3), GA biosynthetic inhibitor paclobutrazol (PAC) and abscisic acid (ABA). The results showed that the expression of BnGID1a and BnSLY1 was down-regulated after treated by GA3 and induced by PAC and ABA. These results suggest that the expression of BnGID1a and BnSLY1 may be negatively regulated by the level of endogenous GA in B. napus. Moreover, BnRGA was not significantly regulated by GA3, PAC and ABA in the low concentrations. These suggest that GA-GID1-SCF-DELLA complex may have a mechanism of self-regulation, thereby preserving the stability of the expression level of BnRGA in B. napus.
KeywordsDELLA protein Gene cloning Gibberellins Abscisic acid Expression Brassica napus
Gibberellin insensitive dwarf 1
This work was supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions, the National ‘863’ Program (SN: 2001AA241104) and the 10th ‘five-year’ key task project in crop breeding of Sichuan Province (SN: 200107001).
- 6.Ikeda A, Ueguchi-Tanaka M, Sonoda Y, Kitano H, Koshioka M, Futsuhara Y, Matsuoka M, Yamaguchi J (2001) S slender rice, a constitutive gibberellin response mutant, is caused by a null mutation of the SLR1 gene, an ortholog of the height-regulating gene GAI/RGA/RHT/D8. Plant Cell 13:999–1010PubMedGoogle Scholar
- 21.Zhao Y, Wang ML, Zhang YZ, Du LF, Pan T (2000) A chlorophyll-reduced seedling mutant in oilseed rape, Brassica napus, for utilization in F1 hybrid production. Plant Breed 119:131–135Google Scholar
- 23.Huapeng Li, Wang Yun, Xiaocheng Li, Gao Yong, Wang Zhijun, Zhao Yun, Wang Maolin (2011) A GA-insensitive dwarf mutant of Brassica napus L. correlated with mutation in pyrimidine box in the promoter of GID1. Mol Biol Rep 38:191–197Google Scholar
- 24.Alvey L, Harberd N (2005) DELLA proteins: integrators of multiple plant growth regulatory inputs? Physiol Plant 123:153–160Google Scholar