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51.
Analyses of wheat/rye addition lines by Southern blotting confirmed the presence of sequences related to theSec 1, Sec 2, andSec 3 loci on chromosomes 1R and 2R. Comparison of the 1R and 2R addition lines allowed the identification of -secalin genes atSec 1 andSec 2, respectively, while -secalin and -secalin genes atSec 1 were discriminated by comparative hybridization with three probes: -secalin, total -secalin, and 3 -secalin. The high molecular weight (HMW) secalin genes atSec 3 were identified using a homologous HMW subunit probe from wheat. Gene copy numbers were estimated as about 40–60 for -secalins, 5–10 for -secalins, and 2 for HMW secalins. Comparison of individual plants of cv. Gazelle showed a high degree of polymorphism, particularly for sequences related to -secalins and HMW secalins. 相似文献
52.
Zora Svab Elisabeth C Harper Jonathan D. G. Jones Pal Maliga 《Plant molecular biology》1990,14(2):197-205
The bacterial gene aad A encodes the enzyme aminoglycoside-3-adenyltransferase that confers resistance to spectinomycin and streptomycin in Escherichia coli. Chimeric genes have been constructed for expression in plants, and were introduced into Nicotiana tabacum by Agrobacterium binary transformation vectors. Spectinomycin or streptomycin in selective concentrations prevent greening of N. tabacum calli. Transgenic clones, however, formed green calli on selective media containing spectinomycin, streptomycin, or both drugs. Resistance was inherited as a dominant Mendelian trait in the seed progeny. Resistance conferred by the chimeric aad A gene can be used as a color marker similar to the resistance conferred by the streptomycin phosphotransferase gene to streptomycin. 相似文献
53.
ABSTRACT. A new species of Amblyospora , a parasite found in wild populations of the predacious Australian mosquito Culex halifaxi , was investigated with light and electron microscopy. This species was found to be heterosporous with two concurrent sporulation sequences in the host larvae, both arising from diplokaryotic meronts and ending with haploid spores. One sequence was dominant and involved meiosis to produce eight thick-walled, broadly oval meiospores in a sporophorous vesicle (SV). The other sequence involved nuclear dissociation to produce lanceolate, thin-walled spores in a subpersistent SV. Horizontal transmission to the mosquito host, by one or both of two distinctly different pathways (one via an intermediate host, the other by cannibalism of infected individuals) and by vertical transmission, are postulated but have not been demonstrated. A new species, Amblyospora trinus , is proposed and its affinities to other heterosporous microsporidia in mosquitoes are discussed. 相似文献
54.
Patricia A. McLenachan Peter J. Lockhart H. Rick Faber Brian C. Mansfield 《Journal of molecular evolution》1996,42(2):273-280
The pregnancy-specific 1-glycoproteins (PSG) form a large family of closely related proteins. Using newly developed methods of sequence analysis, in combination with protein modeling, we provide a framework for investigating the evolution and biological function of genes like the PSG. Evolutionary trees, based on C-terminal sequence, group PSG genes in a manner consistent with their genomic organization. Trees constructed using the N-terminal domain sequences are unreliable as an indicator of phylogeny because of non-neutral processes of sequence change. During duplication of the PSG genes, evolutionary pressures have resulted in a gradient of constrained change across each gene. The N-terminal domains show a nonrandom pattern of amino acid substitutions clustered in the immunoglobulin complementarity-determining region (CDR)-like regions, which appear to be important in the function of the protein. 相似文献
55.
La-orsri Sanoamuang 《Hydrobiologia》1996,339(1-3):23-25
Lecane segersi n.sp. collected from a swamp in Udornthani province, northeastern part of Thailand, is described and figured. It is closely related to the common, warm-stenotherm Lecane papuana (Murray), but distinguished by the presence of inwardly directed antero-lateral spines. 相似文献
56.
Three new Longidorus species, L. alaskaensis n. sp., L. paralaskaensis n. sp., and L. bernardi n. sp., are described from specimens collected near Fairbanks, Alaska. Longidorus alaskaensis differs from all species of Longidorus by the presence of a caecum-like structure situated at the reflex of the oviduct. Longidorus paralaskaensis most closely resembles L. alaskaensis n. sp., L. crassus Thorne, L. picenus Roca, Lamberti &Agostinelli, and L. silvae Roca, differing from the last three of these species by having a parallel vs. a tapered lip region, and from all four by having a more narrowly rounded tail tip. Longidorus paralaskaensis differs from L. alaskaensis by having a longer odontostyle (119-128 vs. 110-118 μm) and by lacking the caecum-like structure found at the reflex of the oviduct. Longidorus bernardi n. sp. most closely resembles L. mirus Khan, Chawla &Seshadri, from which it differs by having a longer tail with a more acutely rounded tip, a longer body length (3.5-4.6 vs. 3.0-3.6 μm), and a larger c'' value (1.6-1.8 vs. 1.3-1.6). Longidorus bernardi differs from L. sylphus Thorne, L. africanus Merny, L. auratus Jacobs &Heyns, and L. conicaudatus Khan by having a slightly expanded lip region vs. a lip region with parallel body walls and a more finely rounded tail tip. 相似文献
57.
J. G. M. van Nistelrooy J. M. van den Brink J. A. L. van Kan R. F. M. van Gorcom M. A. de Waard 《Molecular & general genetics : MGG》1996,250(6):725-733
TheCYP51 gene encoding eburicol 14-demethylase (P45014DM) was cloned from a genomic library of the filamentous fungal plant pathogenPenicillium italicum, by heterologous hybridisation with the corresponding gene encoding lanosterol 14-demethylase from the yeastCandida tropicalis. The nucleotide sequence of a 1739-bp genomic fragment and the corresponding cDNA clone comprises an open reading frame (ORF) of 1545 bp, encoding a protein of 515 amino acids with a predicted molecular mass of 57.3 kDa. The ORF is interrupted by three introns of 60, 72 and 62 bp. The C-terminal part of the protein includes a characteristic haem-binding domain, HR2, common to all P450 genes. The deducedP. italicum P45014DM protein and the P45014DM proteins fromCandida albicans, C. tropicalis andSaccharomyces cerevisiae share 47.2, 47.0 and 45.8% amino acid sequence identity. Therefore, the cloned gene is classified as a member of theCYP51 family. Multiple copies of a genomic DNA fragment ofP. italicum containing the cloned P450 gene were introduced intoAspergillus niger by transformation. Transformants were significantly less sensitive to fungicides which inhibit P45014DM activity, indicating that the cloned gene encodes a functional eburicol 14-demethylase. 相似文献
58.
59.
Trienoic fatty acids, namely -linolenic acid and hexadecatrienoic acid, present in leaf lipids are produced by -3 fatty acid desaturases located in the endoplasmic reticulum and plastid membranes. The changes in the level of trienoic fatty acids during leaf maturation were investigated in wild-type plants of Arabidopsis thaliana (L.) Heynh. and in the fad7 mutant deficient in the activity of a plastid -3 desaturase. The levels of trienoic fatty acids increased in 26 °C- and 15 °C-grown wild-type plants with maturation of leaves. The increase in trienoic fatty acids was mainly due to galactolipids enriched in plastid membranes. In addition, the relative levels of trienoic fatty acids in major glycerolipids, including phospholipids enriched in the endoplasmic reticulum membranes, also increased with leaf maturation. By contrast, when the fad7 mutant was grown at 26 °C, the relative levels of trienoic fatty acids in individual lipids decreased with leaf maturation. The decreases in the levels of trienoic fatty acids, however, were alleviated when the fad7 mutant was grown at 15 °C. These results suggest that the plastid -3 desaturase plays a major role in increasing the levels of trienoic fatty acids with leaf maturation.Abbreviations 163
hexadecatrienoic acid
- 183
-linolenic acid
- DGD
digalactosyldiacylglycerol
- MGD
monogalactosyldiacylglycerol
- PC
phosphatidylcholine
- PE
phosphatidylethanolamine
- TA
trienoic fatty acid
- WT
wild type
- -3
refers to the position of the double bond from the methyl end of a fatty acid
This research was supported in part by Grants-in-Aid for Scientific research (#07251214 and #06804050 to K.I.) from the Ministry of Education, Science and Culture, Japan, and by the research grant from Shorai Foundation. 相似文献
60.
A cDNA clone, pAUK1, with an open reading frame (ORF) coding for a hypothetical 164-amino-acid protein was isolated from an Arabidopsis thaliana (L.) Heynh cDNA library. The clone was attached, tail to tail, to the 3′ end of A. thaliana hexokinase cDNA. An almost identical sequence had been previously described as the 5′ untranslated region (5′ UTR) of A. thaliana calmodulin cDNA (ACaM-2). Sequence comparison with three additional A. thaliana truncated cDNA clones which appear in a database (GenBank) supports the conclusion that pAUKl is identical to the 5′ UTR of ACaM-2 and that the 5′ UTR of ACaM-2 is an independent cDNA artificially linked to A. thaliana calmodulin cDNA. 相似文献