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One of the main limitations of cereal breeding is the lack of genetic variability within cultivated crops. Hordeum chilense is a wild relative of Hordeum vulgare, which has been successfully used in the synthesis of amphiploids by crossing with Triticum spp. Among the agronomic traits of these new amphiploids, the allelic variation in the endosperm storage proteins and their influence on breadmaking and malting quality are of special interest. B-hordeins are sulfur rich prolamins, which account for 70-80% of the total hordein fraction in barley. In this work, rapid amplification of cDNA ends by PCR (RACE-PCR) has been used for the cloning of the full-length open reading frame (ORF) of six sequences of B3-hordeins from two lines of H. chilense. Two consensus sequences of 813 and 822 bp for the H1 and H7 lines, respectively, were determined by alignment of all the sequences generated. Between both lines, differences involving single base changes, which could correspond to single nucleotide polymorphisms (SNP), insertions and deletions were observed. Of these differences, only six out of the 13 within the ORF caused a change of amino acid. Two insertions/deletions of 9 and 12 bp were also observed between both lines. The derived amino acid sequences showed a similar structure to the B-hordeins from cultivated barley and other prolamins. The repetitive region is based on the repetition of the motif PQQPFPQQ. The copy number of the B3-hordeins was estimated as a minimum of nine and five copies for the H1 and H7 lines, respectively. The expression profile of the B-hordeins through the developing endosperm is also described in this work. This study of the storage proteins of H. chilense is a useful contribution to the knowledge of the genetic diversity available in wild relatives of cultivated barley. In addition, the origin of the different prolamins can be better understood with an in-depth knowledge of its wild equivalent.

Hordeum chilense is a wild relative of H. vulgare, cultivated barley, that has been successfully used in the synthesis of amphiploids by crossing with Triticum spp. These amphiploids-named generically x Tritordeum-have been tested under field conditions, and one of them, the hexaploid tritordeum obtained following chromosome doubling of the hybrid H. chilense x T. turgidum, shows traits of interest inherited from the barley parent. Of great interest is the allelic variation observed in the endosperm storage proteins and their influence on the breadmaking and malting quality of tritordeum. We report here two mRNA (cDNA) sequences for a gamma-3 hordein from two accession lines of H. chilense, H1 and H7, and their characterization by quantitative real time (QRT)-PCR in the developing endosperm. Sequences were obtained by rapid amplification of cDNA ends and "edge-to-edge" amplification of open reading frames from cDNA of H. chilense. Eight putative single nucleotide polymorphisms and one codon insertion were identified in the sequences of the H1 and H7 gamma-3 hordeins. The deduced amino acid sequences showed similar features to that of the gamma-3 hordein and gamma-gliadins from barley and wheat, respectively. While the repetitive motif (PQQQPF) is similar to that of the gamma-3 hordein from H. vulgare, there are 19 motif repeats in H. vulgare, whereas H. chilense shows 15 tandem repeats. The transcription of the genes encoding for the gamma-3 hordein were monitored by QRT-PCR: in both lines maximum transcription occurred 12 days after flowering.

[EN] A range of single tagged site (STS), simple sequence repeat (SSR), and sequence-characterized amplified region (SCAR) markers were screened for their utility in detecting Hordeum vulgare and H. chilense chromosomes in a wheat background. PCR conditions were optimized for specific amplification of the targeted sequences and to avoid cross-species amplification. Two H. vulgare derived STSs, six H. vulgare derived SSRs, and nine H. chilense derived SCARs were usable for the detection of five H. vulgare and three H. chilense chromosomes by direct ethidium bromide staining of the PCR products in test tubes, avoiding the more costly and time-consuming DNA electrophoresis step. The practical application of the method is illustrated by the identification of a monotelosomic substitution of H. vulgare chromosome 6HS in tritordeum and a monosomic addition of H. chilense chromosome 6Hch in durum wheat.Key words: GISH, Hordeum chilense, Hordeum vulgare, marker-assisted selection, SSR, Tritordeum., [FR] Un ensemble de marquers de type STS (« single-tagged-site »), microsatellite (SSR) et SCAR (« sequence-characterized amplified region ») ont été examinés quant à leur utilité potentielle pour la détection de chromosomes duHordeum vulgareet duH. chilensedans un fond génétique du blé. Les conditions PCR ont été optimisées pourl’amplification spécifique des séquences ciblées et pour éviter l’amplification croisée entre espèces. Deux marqueursSTS dérivés duH. vulgare, six microsatellites dérivés duH. vulgareet neuf SCAR dérivés duH. chilensepermettaientde détecter cinq chromosomes duH. vulgareet trois chromosomes duH. chilensepar simple détection des ampliconsau bromure d’éthidium dans des tubes réactionnels, évitant ainsi l’étape plus longue et coûteuse de l’électrophorèse.L’intérêt pratique de cette méthode est illustré via l’identification d’une substitution monotélosomique du chromosome6HS duH. vulgarechez une lignée issue d’un croisement blé-orge (tritordeum) ainsi que par l’identification d’une ad-dition monosomique du chromosome 6HchduH. chilensechez le blé durum., Financial support from the Minesterio de Ciencia y Tecnologia, Spain, the Comisión Interministerial de Ciencia yTecnologia (CICYT), Spain (project numbers AGF98-0945-CO2-01 and AGF99-1036-CO2-02), and the Spanish–British Acciones Integradas program (concerted action HB1998-0199) is acknowledged.

The first genetic map of the wild South Ameri- can barley species Hordeum chilense is presented. The map, based on an F2 population of 114 plants, contains 123 markers, including 82 RAPDs, 13 SSRs, 16 RFLPs, four SCARs, two seed storage proteins and two STS markers. The map spans 694 cM with an average distance of 5.7 cM between markers. Six additional SSRs and seven additional SCARs which were not polymorphic were assigned to chromosomes using wheat/H. chilense addition lines. Polymorphisms were revealed by 50% of the RAPD amplifications, 13% of wheat and barley SSR primers, and 78% of the Gramineae RFLP anchor probes. The utility of SSR and RFLP probes from other Gramineae species shows the usefulness of a comparative approach as a source of markers and for aligning the genetic map of H. chilense with other species. This also indicates that the overall structure of the H. chilense linkage groups is probably similar to that of the B and D genomes of wheat and the H genome of barley. Applications of the map for tritordeum and wheat breeding are discussed., Financial support from the Spanish-Britishconcerted action, HB1998–0199, and from the CICYT, Spain (Project number AGF98–0945-CO2–01), is gratefully acknowl-edged.

We have isolated and characterized 47 ultraviolet light-induced hprt mutants from a simian virus 40-transformed excision-repair-deficient xeroderma pigmentosum cell line (complementation group A). Twenty-one independent mutations were found, of which the majority were point mutations. Eleven of these were identified as base changes, nine of which could be attributed to ultraviolet damage on the transcribed DNA strand. Both transitions and transversions were found among the single base changes. A large proportion of the mutations ( 13 21 ) resulted in aberrant splicing of the hprt gene, suggesting that the target size for mutations resulting in aberrant splicing must be quite large. A small number of spontaneous mutations were identified, most of which were large deletions. Our data provide a spectrum for the intrinsic mutations resulting from ultraviolet damage in human cells in the absence of repair.

Homozygous AdhF AdhF and Adhs Adhs lines, collected from the same D. melanogaster winery polymorphic population, were submitted to stress by environmental ethanol. The responses of each of the FF, FS and SS genotypes, for both control and selected lines were analysed in normal and ethanol supplemented medium, in relation to three fitness components: egg-to-adult viability, developmental time and ethanol utilisation. Ethanol selection has resulted in a higher ethanol tolerance, a shorter developmental time and a better ability to use ethanol as food, showing the AdhF AdhF genotype to be that with the highest relative fitness.

The forward mutation assay to L-arabinose resistance (Ara test) in Salmonella typhimurium detected a Spanish red table wine (Rioja) as a direct-acting mutagen. The best mutagenic response was obtained by preincubating strain BA13 with the wine sample in the presence of sodium phosphate buffer and in the absence of any external metabolic activation. In fact, the S9 mixture abolished most of the mutagenic activity of red wine in the Ara test. Such an inactivating capacity seems to be independent of microsomal enzymes and mediated through some kind of heat-stable component(s) in the S9 fraction. Both regular wine (directly from the bottle) and lyophilized wine were strong mutagens in the Ara test, inducing 4914 and 2739 AraR mutants/ml. Both pKM101 and delta uvrB were critical factors in the detection of the mutagenicity of wine, exhibiting a synergic effect in strain BA13. The mutagenicity of red wine was somehow pH-dependent, increasing with the pH value of the preincubation mixture. In comparison with the Ara test, the His reverse mutation assay (Ames test) was much less sensitive to the mutagenicity of lyophilized red wine, TA102 being the most (448 His+/ml) and TA98 the least (38 His+/ml) sensitive strain. TA100, TA104 and TA97 manifested intermediate mutagenicities to red wine. Previous reports have identified strain TA98 as the His strain most sensitive to the apolar fraction (e.g. XAD-2-bound) of red wine. Based on these results we propose that TA98 mainly detects glycosides of mutagenic flavonols present in red wine (quercetin, rutin, etc.), which do not constitute the major direct-acting mutagens detected with the Ara test.(ABSTRACT TRUNCATED AT 250 WORDS)