Over the last few years, a lot of information has been produced on grapevine genome structure and genetic variation within different cultivars. However, little is known on how these sequence variations influence the gene expression and the phenotypes of different cultivars. The family of Wuschel-related Homeobox (WOX) genes is a class of transcription factors involved in the early stages of embryogenesis and organ development in plants. In a previous study conducted in Vitis vinifera some of these genes showed different transcription levels in callus tissues originated from two cultivars characterized by a different embryogenic aptitude (high in 'Chardonnay' and low in 'Cabernet Sauvignon'). Therefore, we are investigating the genetic basis responsible for these differences by cloning and sequencing the promoter region (~2000 bp) proximal to the 5'-end of each VvWOX gene from 'Chardonnay' and 'Cabernet Sauvignon'. The sequences were analysed in silico to identify the nucleotide differences between the promoters isolated from the two cultivars and the cis-acting elements present in these regions. In some of these promoters, we observed several differences between 'Chardonnay' and 'Cabernet Sauvignon' characterized by the absence of some cis-acting elements potentially important for the gene regulation. Therefore, these promoters were introduced in Arabidopsis thaliana for the expression pattern characterization using the GUS reporter gene. Interestingly two promoters (pVvWOX13C and pVvWOX6), having differences in few nucleotides between the sequences isolated from 'Chardonnay' and 'Cabernet Sauvignon', induced different levels of GUS expression in the homozygous F3 generations of transgenic Arabidopsis. These results were further confirmed in transient expression assays using the agroinfiltration approach in grapevine leaves collected from young in vitro plantlets. Therefore, these systems appear to be effective to explore gene modulation linked to intervarietal sequence variation in grapevine.
Cultivar-specific gene regulation in grapevine: analysis of the promoters using heterologous and homologous systems
Boccacci P;Perrone I;Chitarra W;Gribaudo I;Gambino G
2016
Abstract
Over the last few years, a lot of information has been produced on grapevine genome structure and genetic variation within different cultivars. However, little is known on how these sequence variations influence the gene expression and the phenotypes of different cultivars. The family of Wuschel-related Homeobox (WOX) genes is a class of transcription factors involved in the early stages of embryogenesis and organ development in plants. In a previous study conducted in Vitis vinifera some of these genes showed different transcription levels in callus tissues originated from two cultivars characterized by a different embryogenic aptitude (high in 'Chardonnay' and low in 'Cabernet Sauvignon'). Therefore, we are investigating the genetic basis responsible for these differences by cloning and sequencing the promoter region (~2000 bp) proximal to the 5'-end of each VvWOX gene from 'Chardonnay' and 'Cabernet Sauvignon'. The sequences were analysed in silico to identify the nucleotide differences between the promoters isolated from the two cultivars and the cis-acting elements present in these regions. In some of these promoters, we observed several differences between 'Chardonnay' and 'Cabernet Sauvignon' characterized by the absence of some cis-acting elements potentially important for the gene regulation. Therefore, these promoters were introduced in Arabidopsis thaliana for the expression pattern characterization using the GUS reporter gene. Interestingly two promoters (pVvWOX13C and pVvWOX6), having differences in few nucleotides between the sequences isolated from 'Chardonnay' and 'Cabernet Sauvignon', induced different levels of GUS expression in the homozygous F3 generations of transgenic Arabidopsis. These results were further confirmed in transient expression assays using the agroinfiltration approach in grapevine leaves collected from young in vitro plantlets. Therefore, these systems appear to be effective to explore gene modulation linked to intervarietal sequence variation in grapevine.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
