Digestion and detoxification are the two most important functions of the liver, and liver cells always keep a high metabolism level and active vesicular traffic. The malfunction of the vesicular traffic system might be a cause of the abnormal biological behavior of cancerous liver cells. The Ras superfamily is known to regulate various steps of vesicular traffic in eukaryotic cells. It would be significant to determine the change of vesicular transport molecules such as the members of Ras superfamily in carcinogenesis of liver cells. In the present study, we have cloned nine novel genes encoding human small GTPases: RAB1B, RAB4B, RAB10, RAB22A, RAB24, RAB25 ARL5, SARA1, and SARA2, among which the former six belong to the RAB family and the latter three belong to the ARF/SAR1 family. The identification of these new genes has greatly enlarged the pool of the Ras superfamily. It is interesting to find that they are upregulated in most of the 11 hepatocellular carcinoma and 1 cholangiohepatoma cases. Furthermore, the expression in 16 normal human adult tissues, the chromosome loci, and the gene structures of the nine genes are also described. The above findings could be valuable for understanding the vesicular transport system and elucidating the molecular basis of liver cancer carcinogenesis. RABARF/SAR1 Cloning Expression Liver cancer

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In vivo all-trans-retinoic acid (ATRA), a differentiation inducer, is capable of causing clinical remission in about 90% of patients with acute promyelocytic leukemia (APL). The molecular basis for the differentiation ofAPL cells after treatment with ATRA remains obscure and may involve genes other than the known retinoid nuclear transcription factors. We report here the ATRA-induced gene expression in a cell line (NB4) derived from a patient with APL. By differential display-PCR, we isolated and characterized a novel gene (RIG-E) Bands demonstrating reproducible differences were excised from the dried gel. The DNAs were recovered and reamplified by PCR under the conditions as described above with the exception that no radioisotope was used (6). Reamplified PCR products were subcloned into the pGEM-T vector (Promega) according to the manufacturer's instruction.cDNA Library Construction and Isolation of RIG-E cDNA Clone. Oligo(dT)-primed cDNAs were synthesized and size selected by using NB4 cell poly(A) RNA. The cDNAs were introduced into the EcoRI/XhoI site of the Uni-ZAP XR vector to construct library with a ZAP-cDNA synthesis kit (Stratagene). The human adult ventricular muscle cDNA library, prepared in AZAPII (Stratagene) by combined random priming and oligo(dT)-tailed mRNA, was described (8). Libraries were screened by hybridization using 32P-labeled

Wolbachia are maternally inherited, intracellular a-proteobacteria that infect a wide range of arthropods. They manipulate the reproduction of hosts to facilitate their spread into host populations, through ways such as cytoplasmic incompatibility (CI), parthenogenesis, feminization and male killing. The influence of Wolbachia infection on host populations has attracted considerable interest in their possible role in speciation and as a potential agent of biological control. In this study, we used both microinjection and nested PCR to show that the Wolbachia naturally infecting Drosophila simulans can be transferred into a naturally Wolbachiainfected strain of the small brown planthopper Laodelphax striatellus, with up to 30% superinfection frequency in the F 12 generation. The superinfected males of L. striatellus showed unidirectional CI when mated with the original single-infected females, while superinfected females of L. striatellus were compatible with superinfected or single-infected males. These results are, to our knowledge, the first to establish a superinfected horizontal transfer route for Wolbachia between phylogenetically distant insects. The segregation of Wolbachia from superinfected L. striatellus was observed during the spreading process, which suggests that Wolbachia could adapt to a phylogenetically distant host with increased infection frequency in the new host population; however, it would take a long time to establish a highfrequency superinfection line. This study implies a novel way to generate insect lines capable of driving desired genes into Wolbachia-infected populations to start population replacement.

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