Mycotoxins are secondary metabolites with potential dangers for animal and human health. In parti... more Mycotoxins are secondary metabolites with potential dangers for animal and human health. In particular, maize (Zea mays L.) infection caused by Fusarium and the consequent fumonisin contamination is widespread in several countries such as Italy. We developed six maize populations differing in their constitution of regulatory genes able to accumulate respectively anthocyanins in the aleurone layer (r1 gene), pericarp (b1 and pl1 genes) and phlobaphene in the pericarp (p1 gene). These coloured populations, with the related control colourless populations were analysed for mycotoxin content in the kernels during three field seasons with the aim of understanding if there were any correlations with their ability to accumulate flavonoids in kernel tissues. Our results indicate that accumulation of flavonoid pigments in the seeds, in particular phlobaphenes, is able to reduce the level of fumonisin B1. This finding could be used to minimize kernel mycotoxin contamination in this crop, in particular, the development of sweet, pop and polenta coloured corn varieties will help the farmer to keep the level of fumonisin under the threshold of contamination established for human corn consumption.
The completion of the entire Arabidopsis genome sequence has been recently achieved. Approximatel... more The completion of the entire Arabidopsis genome sequence has been recently achieved. Approximately 30% of the predicted genes encode for proteins of unknown function, and only 9% of the genes have been characterized experimentally. Different genetic and molecular tools have been developed to address the functional significance of the genes discovered in EST and genome sequencing programs. Bioinformatic studies can assign putative functions by homology to known genes, while microarray technology can examine global and detailed gene expression patterns. Nevertheless, the identification and characterization of loss-of-function mutations remains a primary tool in functional genomics studies. Insertional mutagenesis approaches are well suited for large-scale functional analysis. Insertions of transposons or T-DNA in specific target genes can be easily detected by reverse genetic PCR-assisted screens. The molecular and phenotypic characterization of the insertional alleles provide vital d...
The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosyntheti... more The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosynthetic pathway, encoding tissue-specific products that are homologous to the helix-loop-helix transcriptional activators. Sn determines the pigmentation of the mesocotyl, leaf basis and pericarp, while R determines pigmentation in various tissues, but not in the mesocotyl. In the progeny derived from test-crosses of R/Sn heterozygous plants, a high frequency of R plants exhibiting mesocotyl pigmentation was observed; these derivatives were defined as R*. In R* plants, the presence of this novel trait was not accompanied by the acquisition of Sn or by gross DNA rearrangements in the R profile. Accordingly, RT-PCR analysis showed that mesocotyl pigmentation in R* was attributable to the resident R gene. The occurrence of R* was observed with all R alleles tested, and was enhanced when a P component was present. The heritability of R* was shown only in the case of the standard R-r allele, which ...
The present invention relates to the expression of recombinant nucleic acids in plants. More spec... more The present invention relates to the expression of recombinant nucleic acids in plants. More specifically the invention provides a promoter for the selective expression of genes in stomatal guard cells, gene constructs containing said promoter, expression vectors thereof and plants transformed therewith. The selective expression of genes in stomatal guard cells allows the regulation of their opening/closing states thereby modulating, e.g. increasing, the plant ability to resist to adverse environmental or climatic conditions
Several tools for genome-wide expression studies have been developed in the recent years, which l... more Several tools for genome-wide expression studies have been developed in the recent years, which led to the identification of many plant genes and proteins involved in different developmental and physiological processes. Yet, the specificity of information derived ...
The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosyntheti... more The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosynthetic pathway, encoding tissue-speci®c products that are homologous to the helix-loop-helix transcriptional activators. Sn determines the pigmentation of the mesocotyl, leaf basis and pericarp, while R determines pigmentation in various tissues, but not in the mesocotyl. In the progeny derived from test-crosses of R/Sn heterozygous plants, a high frequency of R plants exhibiting mesocotyl pigmentation was observed; these derivatives were de®ned as R*. In R* plants, the presence of this novel trait was not accompanied by the acquisition of Sn or by gross DNA rearrangements in the R pro®le. Accordingly, RT-PCR analysis showed that mesocotyl pigmentation in R* was attributable to the resident R gene. The occurrence of R* was observed with all R alleles tested, and was enhanced when a P component was present. The heritability of R* was shown only in the case of the standard R-r allele, which car...
Mycotoxins are secondary metabolites with potential dangers for animal and human health. In parti... more Mycotoxins are secondary metabolites with potential dangers for animal and human health. In particular, maize (Zea mays L.) infection caused by Fusarium and the consequent fumonisin contamination is widespread in several countries such as Italy. We developed six maize populations differing in their constitution of regulatory genes able to accumulate respectively anthocyanins in the aleurone layer (r1 gene), pericarp (b1 and pl1 genes) and phlobaphene in the pericarp (p1 gene). These coloured populations, with the related control colourless populations were analysed for mycotoxin content in the kernels during three field seasons with the aim of understanding if there were any correlations with their ability to accumulate flavonoids in kernel tissues. Our results indicate that accumulation of flavonoid pigments in the seeds, in particular phlobaphenes, is able to reduce the level of fumonisin B1. This finding could be used to minimize kernel mycotoxin contamination in this crop, in particular, the development of sweet, pop and polenta coloured corn varieties will help the farmer to keep the level of fumonisin under the threshold of contamination established for human corn consumption.
The completion of the entire Arabidopsis genome sequence has been recently achieved. Approximatel... more The completion of the entire Arabidopsis genome sequence has been recently achieved. Approximately 30% of the predicted genes encode for proteins of unknown function, and only 9% of the genes have been characterized experimentally. Different genetic and molecular tools have been developed to address the functional significance of the genes discovered in EST and genome sequencing programs. Bioinformatic studies can assign putative functions by homology to known genes, while microarray technology can examine global and detailed gene expression patterns. Nevertheless, the identification and characterization of loss-of-function mutations remains a primary tool in functional genomics studies. Insertional mutagenesis approaches are well suited for large-scale functional analysis. Insertions of transposons or T-DNA in specific target genes can be easily detected by reverse genetic PCR-assisted screens. The molecular and phenotypic characterization of the insertional alleles provide vital d...
The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosyntheti... more The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosynthetic pathway, encoding tissue-specific products that are homologous to the helix-loop-helix transcriptional activators. Sn determines the pigmentation of the mesocotyl, leaf basis and pericarp, while R determines pigmentation in various tissues, but not in the mesocotyl. In the progeny derived from test-crosses of R/Sn heterozygous plants, a high frequency of R plants exhibiting mesocotyl pigmentation was observed; these derivatives were defined as R*. In R* plants, the presence of this novel trait was not accompanied by the acquisition of Sn or by gross DNA rearrangements in the R profile. Accordingly, RT-PCR analysis showed that mesocotyl pigmentation in R* was attributable to the resident R gene. The occurrence of R* was observed with all R alleles tested, and was enhanced when a P component was present. The heritability of R* was shown only in the case of the standard R-r allele, which ...
The present invention relates to the expression of recombinant nucleic acids in plants. More spec... more The present invention relates to the expression of recombinant nucleic acids in plants. More specifically the invention provides a promoter for the selective expression of genes in stomatal guard cells, gene constructs containing said promoter, expression vectors thereof and plants transformed therewith. The selective expression of genes in stomatal guard cells allows the regulation of their opening/closing states thereby modulating, e.g. increasing, the plant ability to resist to adverse environmental or climatic conditions
Several tools for genome-wide expression studies have been developed in the recent years, which l... more Several tools for genome-wide expression studies have been developed in the recent years, which led to the identification of many plant genes and proteins involved in different developmental and physiological processes. Yet, the specificity of information derived ...
The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosyntheti... more The duplicated R and Sn genes are involved in the regulation of the maize anthocyanin biosynthetic pathway, encoding tissue-speci®c products that are homologous to the helix-loop-helix transcriptional activators. Sn determines the pigmentation of the mesocotyl, leaf basis and pericarp, while R determines pigmentation in various tissues, but not in the mesocotyl. In the progeny derived from test-crosses of R/Sn heterozygous plants, a high frequency of R plants exhibiting mesocotyl pigmentation was observed; these derivatives were de®ned as R*. In R* plants, the presence of this novel trait was not accompanied by the acquisition of Sn or by gross DNA rearrangements in the R pro®le. Accordingly, RT-PCR analysis showed that mesocotyl pigmentation in R* was attributable to the resident R gene. The occurrence of R* was observed with all R alleles tested, and was enhanced when a P component was present. The heritability of R* was shown only in the case of the standard R-r allele, which car...
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