Transcription analysis of apple fruit development using cDNA microarrays

The knowledge of the molecular mechanisms underlying fruit quality traits is fundamental to devise efficient marker-assisted selection strategies and to improve apple breeding. In this study, cDNA microarray technology was used to identify genes whose expression changes during fruit development and maturation thus potentially involved in fruit quality traits. The expression profile of 1,536 transcripts was analysed by microarray hybridisation. A total of 177 genes resulted to be differentially expressed in at least one of the developmental stages considered. Gene ontology annotation was employed to univocally describe gene function, while cluster analysis allowed grouping genes according to their expression profile. An overview of the transcriptional changes and of the metabolic pathways involved in fruit development was obtained. As expected, August and September are the two months where the largest number of differentially expressed genes was observed. In particular, 85 genes resulted to be up-regulated in September. Even though most of the differentially expressed genes are involved in primary metabolism, several other interesting functions were detected and will be presented

Activity of wild-type and hybrid Bacillus thuringiensis delta-endotoxins against Agrotis ipsilon

Twelve Cry1 and two Cry9 ?-endotoxins fromBacillus thuringiensis were tested for their activity against black cutworm (Agrotis ipsilon).A. ipsilon was not susceptible to many toxins, but three toxins had significant activity. Cry9Ca was the most toxic, followed by Cry1Aa and Cry1Fb. Hybrids between these three active proteins were made by in vivo recombination and analyzed for activity againstA. ipsilon. Analysis of hybrids between Cry1Aa and Cry1Fb indicated that domain I of Cry1Aa protein was involved in its higher activit

A novel Cry9Aa with increased toxicity for Spodoptera exigua (Hübner)

Cry9Aa, produced by Bacillus thuringiensis is reported to be not active against Spodoptera exigua (beet armyworm). In this study we have cloned a new cry9Aa5 gene encoding a protoxin with increased activity against S. exigua as compared to Cry9Aa1. When aligned to Cry9Aa1, four amino acid substitutions in domain I and one substitution in the C-terminal protein extension of Cry9Aa5 were identified. Toxicity of Cry9Aa5, produced in recombinant Escherichia coli was assessed and compared to the activity of Cry9Aa1, produced under the same conditions