Submitted to: Plant Molecular Biology Reporter
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2012
Publication Date: 4/10/2012
Citation: Wen, Z., Gao, M., Wang, Q., Xu, H., Walter, M., Xu, W., Bassett, C.L., Wang, X. 2012. Characterization and expression analysis of a Retinoblastoma-related gene from Chinese wild Vitis pseudoreticulata. Plant Molecular Biology Reporter. DOI: 10.1007/s11105-011-0410-6. Interpretive Summary: A family of retinoblastoma-related genes associated with critical cell functions in animals is found in all higher forms of life, but their role in plants is not understood. The current manuscript describes the isolation and characterization of such a gene from grape. Based on comparison of expression of this gene in resistant and susceptible lines of grape, the authors conclude that this gene contributes to some aspect of powdery mildew resistance and could be used in novel ways to prevent infection of important crops.
Technical Abstract: Retinoblastoma-related (RBR) genes, a conserved gene family in higher eukaryotes, plays an important role in cell differentiation, development and mammalian cell death in animals; however, little is known about its function in plants. In this study, an RBR gene was isolated from the Chinese wild grape, Vitis pseudoreticulata W. T. Wang, clone ‘Baihe-35-1’, and designated as VpRBR. The cDNA sequence of VpRBR was 3030 bp and contained an open reading frame of 3024 bp. Conceptual translation of this gene indicated a composition of 1007 amino acids with a predicted molecular mass of 117.3 kDa. The predicted protein showed a retinoblastoma-associated protein domain A from amino acid residues 416 to 579, and domain B from residues 726 to 855. The result of expression analysis indicated that VpRBR was expressed in tissues, leaves, stem, tendrils, flower and grape skin at different expression levels. Further quantitative Reverse Transcription-PCR (qRT-PCR) data indicated that VpRBR levels were higher in Erysiphe necator-treated ‘Baihe-35-1’ and ‘Baihe-13-1’, two resistant clones of Chinese wild Vitis, than in E. necator-treated ‘Hunan-1’, a susceptible clone of V. pseudoreticulata. Furthermore, the expression of VpRBR in response to salicylic acid (SA), methyl jasmonate (MeJA) and ethylene (Eth) in grape leaves was also investigated. Taken together, these data indicate that VpRBR may contribute to some aspect of powdery mildew resistance in grape.