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International audience; Currently, the most widely used strategies for molecular cloning are sticky-end ligation-based cloning, TA cloning, blunt-end ligation-based cloning and ligase-independent cloning. In this study we have developed a novel mini-vector pANY1 which can simultaneously meet the requirements of all these cloning strategies. In addition, the selection of appropriate restriction digestion sites is difficult in some cases because of the presence of internal sites. In this study, an annealing of PCR products (APP)-based sticky-end cloning strategy was introduced to avoid this issue. Additionally, false positives occur during molecular cloning, which increases the workload of isolating positive clones. The plasmid pANY1 contains a ccdB cassette between multiple cloning sites, which efficiently avoids these false positives. Therefore, this mini-vector should serve as a useful tool with wide applications in biosciences, agriculture, food technologies, etc.

International audience; Rat mast cell protease of type 1 (RMCP1) is a specific marker of connective tissue mast cells selectively occurring in some tissues, e.g., the tongue. Its amino acid sequence is known (Le Trong et al., Biochem. 1987, 26, 6988-6994) but not the corresponding nucleotide sequence. Amplification of mRNAs from rat tongue was performed by reverse transcriptase-polymerase chain reaction (RT-PCR) using oligonucleotide primers corresponding to the translated region of rat mast cell protease 2 (RMCP2) gene. The cDNA obtained was subcloned and sequenced, leading to an amino acid sequence which matched the known 227 amino acid sequence. In addition there was, however, two sequences of 11 amino acids at the N-terminus and 13 amino acids at the C-terminus. The amino acid identity was of 74% with RMCP2, and of 76%, 65% and 90% with the mouse proteases MMCP1, MMCP2 and MMCP4, respectively. Based on the sequence of RMCP1 or RMCP2 cDNAs, selective oligoprobes were designed and their specificity established by Northern blot analysis of mRNAs purified from tongue and jejunum, two tissues containing selectively type 1 and 2 protease, respectively. Single 1.2 and 1.0 kb transcripts were evidenced in tongue and jejunum, respectively. In addition, a RT-PCR method was developed to amplify selectively each transcript which may serve as reliable markers in the analysis of mast cell heterogeneity, differentiation and function.

International audience; c-Rmil is the cellular allele of the v-Rmil oncogene, transduced during in vitro passaging of Rous associated virus type 1 in chicken embryonic neuroretina (NR) cells. The c-Rmil proto-oncogene is the avian homolog of the mammalian B-raf gene and belongs to the mil/raf oncogene family of serine/threonine protein kinases. We recently reported that the avian c-Rmil gene encodes two proteins of 94 and 95 kDa, resulting from an alternative splicing mechanism. We describe here the exon-intron organization of the coding region of the chicken c-Rmil locus. We show that c-Rmil proteins are encoded by 19 exons lying within about 100 kbp of genomic DNA. Comparison of the organization of this gene with those of the other mil/raf genes shows strong similarities within three conserved domains previously identified in mil/raf protein kinases. However, c-Rmil contains two additional 5' coding exons that are not present in the other mil/raf genes.

International audience; Using a strategy based upon nucleotide sequence homology and starting from the sequence of the rat histamine H2 receptor (Ruat et al., Biochem. Biophys. Res. Commun. 1991, 179, 1470-1478), we have cloned a rat cDNA encoding a functional serotonin receptor (5-HT6). Its coding sequence corresponds to a glycoprotein of 436 amino acids displaying significant homology with other cloned monoaminergic receptors, e.g., various serotonin receptors. Genomic analysis of its gene indicated the presence of at least one intron. The major transcript of the 5-HT6 receptor gene has a size of approximately 4.1 kb but another minor 3.2 kb transcript was also evidenced. The highest expression, detected by Northern blot analysis as well as by in situ hybridization occurs in various serotoninergic areas of rat or guinea pig brain such as striatum, olfactory tubercle, nucleus accumbens and hippocampus, but a faint expression is also detectable in rat stomach. When transiently expressed in transfected COS-7 cells the 5-HT6 receptor appears to be positively coupled to cyclic AMP production.

International audience; We have screened a rat genomic library using DNA probes derived from the sequence of a recently cloned canine histamine H2 receptor (Gantz et al., Proc. Natl. Acad. Sci. USA 1991, 88, 429-433). An intronless gene, encoding a 358 amino acid protein displaying all major features of G protein-coupled receptors and a 82% overall homology with the canine histamine H2 receptor, was isolated. Northern blot analysis, performed with a probe derived from the rat sequence, revealed a single approximately 6.0 kb transcript in various rat tissues. In the brain, this transcript is highly expressed in brainstem and, to a lesser extent, cerebral cortex, striatum, hippocampus and hypothalamus. These localizations are consistent with the distribution of the H2 receptor in this species. Among peripheral tissues, the stomach highly expresses the transcript which could not be detected in various other organs. All these features, together with the expression of the cloned gene in mammalian cells (Traiffort et al., submitted), are consistent with the idea that a single rat H2 receptor is encoded by the cloned gene.