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131.
Genomes of three alloplasmic wheat lines obtained on the basis of barley--wheat hybrid Horderum geniculatum All. (2n = 28) x Triticum aestivum L. (2n = 42)(Pyrotrix 28) were examined using random amplified polymorphic DNA (RAPD) analysis. Line L-29 was obtained after first backcross of the initial hybrid with the wheat variety Pyrotrix 28 and ten subsequent self-pollinating generations. This line was represented by euploid plants with typical to the common wheat chromosome number (2n = 42), as well as by aneuploids, which contained an additional telocentric chromosome in the main karyotype (2n = 42 + t). Lines L-26 and L-27 were obtained by two backcrosses of one BC1 plant with the wheat variety Novosibirskaya 67 and one subsequent self-polination of one BC3 plant. Chromosome number in all these plants corresponded to 2n = 40 + 4t. RAPD analysis was carried out using seven primers, which were previously proved to be effective for identification of the barley genome fragments within hybrid genomes of alloplasmic lines. The presence of barley genome fragments in line L-29 was revealed by use of five primers, while in lines L-26 and L-27 these fragments were detected by use of one primer. The significant difference in the number of barley RAPD fragments in the genomes of alloplasmic lines obtained at different backcrossing stages suggests more intense displacement of barley genome during backcrossing compared to self-pollination in BC1 plants. 相似文献
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133.
Multiple isoforms of UDP-GalNAc:polypeptide N-acetylgalactosaminyl-
transferase (ppGaNTase) have been cloned and expressed from a variety of
organisms. In general, these isoforms display different patterns of
tissue-specific expression, but exhibit overlapping substrate
specificities, in vitro . A peptide substrate, derived from the sequence of
the V3 loop of the HIV gp120 protein (HIV peptide), has previously been
shown to be glycosylated in vitro exclusively by the ppGaNTase-T3 (Bennett
et al. , 1996). To determine if this isoform- specificity is maintained in
vivo , we have examined the glycosylation of this substrate when it is
expressed as a reporter peptide (rHIV) in a cell background (COS7 cells)
which lacks detectable levels of the ppGaNTase-T3. Glycosylation of rHIV
was greatly increased by coexpression of a recombinant ppGaNTase-T3.
Overexpression of ppGaNTase- T1 yielded only partial glycosylation of the
reporter. We have also determined that the introduction of a proline
residue at the +3 position flanking the potential glycosylation site
eliminated ppGaNTase- T3 selectivity toward rHIV observed both in vivo and
in vitro .
相似文献
134.
MANUEL B. CRESPO ANTONIO DE LA TORRE JOSE L. SOLANAS 《Botanical journal of the Linnean Society. Linnean Society of London》1994,116(2):135-144
Linaria arabiniana sp. nov. is described from coastal sand dunes of a very reduced area in Alicante Province (south-eastern part of the Iberian Peninsula). It is a perennial herb characterized by its 3–4-verticillate leaves, glabrous stems, large violet or rarely yellow flowers, and bicoloured usually flat seeds. Morphological characteristics and taxonomic affinities of this taxon are discussed, as are data on its ecology, phytosociology, and eventual conservation features. 相似文献
135.
Bulbs were obtained on onion plants cultured in vitro. No bulbinghappened under long days with fluorescent light and 3040g l1 sucrose. Bulb formation was mainly dependent eitheron sucrose concentration in the culture medium, or on lightspectral composition. Raising the sucrose concentration from40 to 120 g l1 increased plant basal swelling and stoppedfurther vegetative development. These plants were not dormant.When fluorescent light was enriched in incandescence duringa long day period, bulbs were obtained in two months and underwenta consecutive dormancy. Bulb, dormancy, light spectral quality, photoperiod, R: FR ratio, sugar, tissue culture 相似文献
136.
The first Australian record of the lily thrips, Liothrips vaneeckei Priesner, is reported from a bulb farm in Warragul South, Victoria. It is an occasional pest of Lilium bulbs, both in the field and in storage, particularly in the USA and several European countries, and is also infrequently found in considerable numbers on the corms of orchids. 相似文献
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