The polymerase chain reaction (PCR) is an attractive technique for many genome mapping and characterization projects. One PCR approach which has been evaluated involves the use of randomly amplified ...polymorphic DNA (RAPD). An alternative to RAPDs is the sequence-tagged-site (STS) approach, whereby PCR primers are designed from mapped lowcopy-number sequences. In this study, we sequenced and designed primers from 22 wheat RFLP clones in addition to testing 15 primer sets that had been previously used to amplify DNA sequences in the barley genome. Our results indicated that most of the primers amplified sequences that mapped to the expected chromosomes in wheat. Additionally, 9 of 16 primer sets tested revealed polymorphisms among 20 hexaploid wheat genotypes when PCR products were digested with restriction enzymes. These results suggest that the STS-based PCR analysis will be useful for generation of informative molecular markers in hexaploid wheat.
The v‐cbl oncogene is the transforming gene of the murine Cas NS‐1 retrovirus which induces pre‐B cell lymphomas and myeloid leukaemias. Sequencing of c‐cbl has revealed that v‐cbl was generated by a ...large truncation that removed 60% of the C‐terminus of the corresponding protein. In this study we prepared antibodies to cbl and found that c‐cbl encodes a 120 kDa protein which is localized in the cytoplasm with a cytosolic and cytoskeletal distribution. Immunofluorescence studies show a striking pattern of brightly staining vesicles in mitotic cells similar to that observed with cytokeratin antibodies. In contrast to p120c‐cbl, which is exclusively cytoplasmic, the p100gag‐v‐cbl encoded by Cas NS‐1 is localized in both the cytoplasm and the nucleus. This redistribution to the nucleus correlates with the ability of cbl to induce acute transformation. Furthermore the truncated protein encoded by v‐cbl can bind DNA, unlike the full‐length protein. These results suggest that the C‐terminus of cbl is involved in the retention of p120c‐cbl in the cytoplasm and the inhibition of DNA binding. The findings also suggest that a truncated protein encoded by c‐cbl exists in the nucleus of normal cells.
Quantitative trait locus (QTL) main effects and QTL by environment (QTL x E) interactions for seven agronomic traits (grain yield, days to heading, days to maturity, plant height, lodging severity, ...kernel weight, and test weight) were investigated in a two-row barley (Hordeum vulgare L.) cross, Harrington/TR306. A 127-point base map was constructed from markers (mostly RFLP) scored in 146 random double-haploid (DH) lines from the Harrington/TR306 cross. Field experiments involving the two parents and 145 random DH lines were grown in 1992 and/or 1993 at 17 locations in North America. Analysis of QTL was based on simple and composite interval mapping. Primary QTL were declared at positions where both methods gave evidence for QTL. The number of primary QTL ranged from three to six per trait, collectively explaining 34 to 52% of the genetic variance. None of these primary QTL showed major effects, but many showed effects that were consistent across environments. The addition of secondary QTL gave models that explained 39 to 80% of the genetic variance. The QTL were dispersed throughout the barley genome and some were detected in regions where QTL have been found in previous studies. Eight chromosome regions contained pleiotropic loci and/or linked clusters of loci that affected multiple traits. One region on chromosome 7 affected all traits except days to heading. This study was an intensive effort to evaluate QTL in a narrow-base population grown in a large set of environments. The results reveal the types and distributions of QTL effects manipulated by plant breeders and provide opportunities for future testing of marker-assisted selection
Predictive inferencing was evaluated in 13 adults with right hemisphere damage (RHD) and 11 adults without brain damage (NBD). Brief narrative stimuli that strongly suggested a single outcome were ...constructed to vary recency of mention of inference-related information. Reading times were recorded for narrative-final sentences that disconfirmed the target inferences. Slowed reading time on the final sentences was an indicator of inference generation. Adults with RHD generated target predictive inferences in contexts with recent mention of strongly biasing inference-related information. This group also evidenced maintenance of inferences over time, but to a lesser degree than participants in the NBD group. Overall, individuals with better auditory comprehension or larger estimated working memory capacity tended to maintain inferences better than did the other participants. The results are discussed in relation to current hypotheses of inferencing and discourse comprehension in adults with RHD.
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