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Grapevine (Vitis vinifera) berry development involves a succession of physiological and biochemical changes reflecting the transcriptional modulation of thousands of genes. Although recent studies have investigated the dynamic transcriptome during berry development, most have focused on a single grapevine variety, so there is a lack of comparative data representing different cultivars. Here, we report, to our knowledge, the first genome-wide transcriptional analysis of 120 RNA samples corresponding to 10 Italian grapevine varieties collected at four growth stages. The 10 varieties, representing five red-skinned and five white-skinned berries, were all cultivated in the same experimental vineyard to reduce environmental variability. The comparison of transcriptional changes during berry formation and ripening allowed us to determine the transcriptomic traits common to all varieties, thus defining the core transcriptome of berry development, as well as the transcriptional dynamics underlying differences between red and white berry varieties. A greater variation among the red cultivars than between red and white cultivars at the transcriptome level was revealed, suggesting that anthocyanin accumulation during berry maturation has a direct impact on the transcriptomic regulation of multiple biological processes. The expression of genes related to phenylpropanoid/flavonoid biosynthesis clearly distinguished the behavior of red and white berry genotypes during ripening but also reflected the differential accumulation of anthocyanins in the red berries, indicating some form of cross talk between the activation of stilbene biosynthesis and the accumulation of anthocyanins in ripening berries.

Human herpesvirus 6 (HHV-6) has been frequently isolated from immunocompromised patients. To determine if a routine survey of HHV-6 infection is needed after organ transplantation, as is the case for human cytomegalovirus infection, we observed patients who had received kidney, liver, and kidney-liver transplants; these patients were followed up for the first 3 months after transplantation. HHV-6 infection was diagnosed by isolation of the virus and by the results of serological tests. Antibodies to HHV-6 were detected in 28 (87.5%) of the 32 recipients, before the transplant, whereas only 4 (12.5%) of the 32 recipients were seronegative for HHV-6. After en­ graftment, HHV-6 infection occurred in 10 (31%) of the 32 recipients; infection was diagnosed by isolation of the virus (6 of 32 recipients) or by the results of serological tests (4 of 32 recipients). Regardless of whether they had HHV-6 primary infection or reactivation, severe clinical manifesta­ tions were observed only in patients who had concomitant cytomegalovirus infection, and no correla­ tion could be found between graft rejection and HHV-6 infection. These results suggest that HHV-6 infection occurs frequently in organ transplant recipients and that it is usually not associated with severe clinical manifestations unless accompanied by a concomitant CMV infection. Human herpesvirus 6 (HHV-6) was isolated for the first time in 1986 from the blood of patients with lymphoproliferative disorders [1]. More than 80% ofthe adult population worldwide is infected with HHV-6. Primary infections occur early in child­ hood and may cause exanthema subitum. All other herpesvi­ ruses, and especially human cytomegalovirus (CMV), have been implicated as a primary cause of morbidity and mortality in immunosuppressed transplant recipients. HHV-6 infections have also been reported in organ transplant recipients [2,3]. To determine if HHV-6 could account for clinical manifestations observed in organ transplant recipients, we performed a longi­ tudinal study based on isolation of both HHV-6 and CMV.