The cauliflower mosaic virus translational transactivator interacts with the 60S ribosomal subunit protein L18 of Arabidopsis thaliana

The cauliflower mosaic virus (CaMV) open reading frame VI product (P6) is involved in several aspects of the infectious cycle. P6 specifically controls the synthesis of other CaMV proteins by transactivating their expression from the polycistronic 35S RNA. By far-Western assays, we have demonstrated that P6 interacts with proteins from both healthy and CaMV-infected leaves of Arabidopsis thaliana. These proteins are found in ribosome-enriched extracts, suggesting that they participate in the translation process. One of these proteins, identified by microsequencing, corresponds to the 60S ribosomal subunit protein L18 (RPL18). Its cDNA was cloned and expressed in Escherichia coli, and the resulting RPL18 protein was shown to interact with the minimal region required for translational transactivation, designated the miniTAV domain of P6.     

Lack of association between serotonin transporter gene promoter variants and autistic disorder in two ethnically distinct samples

Family-based studies performed to date provide conflicting evidence of linkage/association between autistic disorder and either the "short" [Cook et al., 1997: Mol Psychiatry 2:247-250] or the "long" [Klauck et al., 1997: Hum Mol Genet 6:2233-2238] allele of a polymorphic repeat located in the serotonin transporter (5-HTT) gene promoter region, affecting 5-HTT gene expression [Lesch et al., 1996: Science 274:1527-1531]. The present study was designed to assess linkage and linkage disequilibrium in two new ethnically distinct samples of families with primary autistic probands. The 5-HTT promoter repeat was genotyped in 54 singleton families collected in Italy and in 32 singleton and 5 multiplex families collected in the U.S.A., yielding a total sample of 98 trios. Linkage/association between 5-HTT gene promoter alleles and autistic disorder was assessed using the transmission/disequilibrium test (TDT) and the haplotype-based haplotype relative risk (HHRR). Both the Italian and the American samples, either singly or combined, displayed no evidence of linkage/association between 5-HTT gene promoter alleles and autistic disorder. Our findings do not support prominent contributions of 5-HTT gene variants to the pathogenesis of idiopathic infantile autism. Heterogeneity in pathogenetic mechanisms underlying the disease may require that linkage/association studies be targeted toward patient subgroups isolated on the basis of specific biochemical markers, such as serotonin (5-HT) blood levels. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:123-127, 2000.     

Analysis with solid phase reagent carriers

Solid-phase chemistry is a category of analytical techniques characterized by three features: dry reagents fixed on or in an inert carrier; they are transformed into a liquid state of reactivity solely by fluid from the sample, movement of fluid in the carrier happens through capillary surface forces. A number of industrial laboratories have adapted these technologies to a majority of parameters of blood or serum respectively. The most frequently used measuring devices are new developed reflectometers; in one system (Ektachem) disposable ion selective electrodes have been newly developed in addition. The most important systems on the market are Ektachem (Kodak), Reflotron (Boehringer, Mannheim) and Seralyzer (Ames). These systems differ with respect to the construction of the reagent carriers and of the reflectometers. Solid-phase chemistry has the following advantages over the conventional analytical techniques: The sample volume is small, and the instrumentation is not complicated. The reagents are ready for use, and one system permits the use of whole blood without centrifugation. In this way it is possible to perform decentralized analyses at the patient's bedside, or in the physician's office. The disadvantages are the complete dependency of the user on the manufacturer with respect to the methodology and the quality of the reagents and instrumentation, the relative high price of the test-elements, and the limited possibility for the processing of long series. Additional problems are associated with quality control and drug interference. Nevertheless it can be expected that in the future increasing numbers of clinical chemical analyses will be performed by solid-phase chemistry, especially in general practice.     

Concurrence of fragile X syndrome and 47, XYY in an individual with a Prader-Willi-like phenotype

We report on a 34-year-old developmentally disabled man referred to our clinic for evaluation of possible Prader-Willi syndrome on the basis of obesity and voracious appetite. Cytogenetic and molecular analysis revealed a 47, XYY karyotype and the presence of a trinucleotide repeat expansion resulting in fragile X syndrome. To our knowledge, this is the first report of concurrence of XYY and fragile X syndrome in the medical literature. Review of sex chromosome abnormalities associated with fragile X syndrome and phenotypic considerations are presented.     

Untersuchungen über den Kohlenhydrat- und Fettstoffwechsel bei körperlicher Arbeit

Ohne Zusammenfassung     

Gene transfer by adenovirus-mimetic peptides in the presence of a cationic lipid and/or adenovirus. Analysis of the contribution of the viral and nonviral components

Summary.  Peptide and cationic lipid-based gene transfer vectors have shown promise for gene therapy but are still less efficient than viral gene transfer vectors. We have examined the mechanism of gene transfer of different adenovirus-mimetic peptides in the presence and absence of a cationic lipid, lipofectamine and/or adenovirus with the aim of improving the design of nonviral vectors for efficient gene transfer. Three polylysine-adenovirus-mimetic peptides were synthesised and examined for their efficacy for gene transfer. Transfection levels in four cell lines: adenovirus permissive human tracheal epithelial (56FHTE8o⁻), human lung carcinoma (A549), human colon carcinoma (Caco-2) cells, and adenovirus low-permissive Chinese hamster ovary (CHO) cells, were examined. The polylysine-adenovirus-mimetic peptides increased the level of transfection of a reporter transgene in all cell lines. Transfection was substantially increased when an adenovirus was added to cells after pre-incubation with the vector complexes. Formulation of the peptide vector complexes with lipofectamine increased their transfection efficacy and the subsequent addition of an adenovirus increased transfection levels even further but only in permissive cells. Pre-incubation of cells with lipofectamine-peptide vector complexes increased cell binding of the adenovirus but uptake was only increased in intermediate- or non-permissive cells. The addition of lipofectamine increased transgene expression of a recombinant adenovirus in non-permissive cells but not in permissive cells. Enhancement with an adenovirus of peptide vector gene transfer is probably due to more efficient endosome escape while enhancement of gene transfer by peptide vectors complexed to lipofectamine is due to an increase in cellular binding and/or internalisation of the adenovirus. Received February 8, 2002; accepted August 23, 2002