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PubMed1992

The structure of variation in affect among depressed and nondepressed elders.

The intraindividual variability of self-ratings of 10 affects was studied in 69 older residents of a long-term care facility. Each person rated his or her affective state over 30 days. P-technique factor analysis was applied to each subject's ratings. In general, the expected two-factor structure showing one positive and one negative factor emerged from both traditional R-analysis and from "chain P-analysis" (all subjects' ratings pooled after standardizing within subjects). Because many subjects gave invariant ratings on one or more affect terms, only 28 P-analyses could be performed, of which 12 yielded one-factor solutions, 16 yielded two-factor solutions (10 the expected two factors), and 5 failed to converge. Possible reasons for the only partial intraindividual replication of the interindividual factors are discussed.

Affect↗
PubMed1997

Simulation of alternative binding modes in a structure-based QSAR study of HIV-1 protease inhibitors.

We have used a published set of inhibitors of HIV-1 protease to build a COMBINE-type structure-based QSAR model with good predictive ability (r2 = 0.90, q2 = 0.69). Since the compounds in the training series exhibit most of their structural variability on one-half of the pseudosymmetrical binding cavity and only one binding orientation was explored for each molecule, the model describes mainly the effect of the structural changes on interactions involving only one-half of the binding cavity (pockets S1' and S2'). Thus, the model cannot be expected to give accurate predictions for new compounds exhibiting structural variation in both halves. The model does in fact show a tendency to underpredict slightly the biological activity of the molecules in the external test set. In an attempt to improve the quality of the model, both possible orientations of the ligands are now considered so that structural variation takes place in all binding pockets. One possibility would have been to build an additional set of complexes with the inhibitors docked in a reversed orientation. The alternative we have explored, however, consists of manipulating the data matrix describing the interaction energies so that each row is duplicated and the order of the variables in the duplicated rows is swapped between subunits. This simple approach has produced a new model that is similar in quality to the original model (r2 = 0.89, q2 = 0.64) but lacks the tendency to underpredict the activity of the compounds in the external set. Moreover, since equivalent residues are assigned equivalent weights, the model is insensitive to ligand orientation and is easier to interpret.

Artificial Intelligence↗
PubMed2000

Sequence variation and structural conservation in the D-loop region and flanking genes of mitochondrial DNA from Japanese pond frogs.

The nucleotide sequences of the D-loop region and its flanking genes of the mitochondrial DNA (mtDNA) from Japanese pond frogs were determined by the methods of PCR, cloning, and sequencing. The frogs belonged to two species, one subspecies, and one local race. The gene arrangements adjacent to the D-loop region were analyzed. The frogs shared a unique mitochondrial gene order that was found in Rana catesbeiana; i.e., cyt b--D-loop region--tRNA(Leu(CUN))--tRNA(Thr)--tRNA(Pro)--tRNA(Phe)--12S rRNA. The arrangements of the three tRNA genes of these frogs were different from those of X. laevis, a species which has the same overall structure as in mammals. Highly repetitive sequences with repeat units (16-bp or 17-bp sequence specific for each taxon) were found in the D-loop region. The length of repetitive sequences varied from 0.6 kbp to 1.2 kbp, and caused the extensive size variation in mtDNA. Several short sequence elements such as putative TAS, OH, CSB-1, and CSB-2 were found in the D-loop region of these frogs. The sequences of these short regulatory elements were conserved in R. catesbeiana, X. laevis, and also in human. The comparison of sequence divergences of the D-loop region and its adjacent genes among various taxa revealed that the rates of nucleotide substitutions depend on genes. The nucleotide sequences of the 3'-side segment of the D-loop region were the most variable among taxa, whereas those of the tRNA and 12S rRNA genes were the most conservative.

Animals↗
PubMed2005

Angulation, length, and morphology of the styloid process of the temporal bone analyzed by multidetector computed tomography.

PURPOSE: To investigate the angulation, length, and structural variations of the styloid process (SP) by multidetector computed tomography (MDCT). MATERIAL AND METHODS: MDCT scans were performed in 283 cases (127 M and 156 F, age range 18-77 years). The length of the SP and its angulation on the transverse and sagittal planes were measured. Structural variations of the SP were observed by means of three-dimensional (3D) and multiplanar reconstruction (MPR) images. RESULTS: The length of the bony SP on both sides varied from 0 to 62 mm (mean 26.8 +/- 10.0 mm). Angulation ranged between 55 degrees and 90.5 degrees (7 2.7 +/- 6.6) in the transversal plane and between 76 degrees and 110 degrees (93.5 +/- 6.9) in the sagittal plane. Morphologically, the SP showed a considerable amount of variation. A solitary SP was present in 168 individuals (59.4%). In 9 individuals (3.1%), the SP was duplicated (4 unilateral and 5 bilateral). Sixty-one persons (21.6%) showed an incomplete ossified SP (42 unilateral and 19 bilateral), whereas in 7 individuals (2.5%) a bony SP was absent entirely (7 unilateral). In 38 individuals (13.4%), the stylohyoid ligament was ossified (16 entirely, 22 partial). In all individuals, 3D and MPR images showed the SP in its entire length. CONCLUSION: MDCT with 3D CT and MPR of SP may show further detailed information related to SP. Not only the length of the SP, but also its 3D orientation, should be in focus in anatomical and clinical studies.

Adolescent↗
PubMed2026

Plastid genome evolution and phylogenomics with broad taxon sampling: insights into intrafamilial classification of Hamamelidaceae.

Hamamelidaceae, within the order Saxifragales, comprises 27 genera and approximately 120 species. The family has a pantropical and temperate distribution across the Americas, Asia, Africa, and Australia. Previous molecular investigations, constrained by limited taxon sampling and inadequate genetic markers, supported a five-subfamily classification system. However, these studies predominantly focused on Asian taxa, resulting in poor resolution of the evolutionary relationships among American, African, and Australian genera. To address these sampling gaps, we employed near-complete generic sampling (26 of 27 genera) to investigate plastome architecture, structural variation, and phylogenetic relationships. We newly sequenced and assembled 15 plastid genomes representing geographically and taxonomically underrepresented genera and analyzed them alongside 59 publicly available plastomes retrieved from GenBank. Plastid genomes exhibited conserved quadripartite architecture with sizes ranging from 158, 076 bp to 160, 814 bp, minimal structural variation, consistent GC content (37.7-38.2%), and identical gene order. Inverted repeat (IR) regions had limited size variation (26, 211-26, 429 bp). Simple sequence repeat (SSR) distribution (2, 219 loci) showed no clear correlation with the genus-level phylogenetic relationships. We identified ten hypervariable regions, including coding sequences (accD, ycf1, clpP, ndhF, and rpl22) and intergenic spacers (rpl33-rps18, the trnG-UCC intron, trnH-GUG-psbA, accD-psaI, and petA-psbJ), as promising candidate regions for future applications in species delimitation and phylogenetic studies. Phylogenetic analyses revealed largely congruent topologies across datasets and methods, providing improved resolution and strong support for most subfamilial and tribal relationships compared with previous studies. This study highlights the utility of plastid genome data for resolving deep-level phylogenetic relationships within Hamamelidaceae. The genome architecture reflects the high conservation of plastid genomes, while the identified mutation hotspots represent potential resources for future taxonomic and phylogenetic studies. Our results support the existing subfamily classification while improving geographical coverage and generic representation, providing a robust framework for future taxonomic and evolutionary studies of this globally distributed and taxonomically complex family.

Hamamelidaceae↗
PubMed2004

Influence of growth temperature on lipid and phosphate contents of surface polysaccharides from the antarctic bacterium Pseudoalteromonas haloplanktis TAC 125.

The chemical structural variations induced by different growth temperatures in the lipooligosaccharide and exopolysaccharide components extracted from the Antarctic bacterium Pseudoalteromonas haloplanktis TAC 125 are described. The increase in phosphorylation with the increase in growth temperature seems to be general, because it happens not only for the lipooligosaccharide but also for the exopolysaccharide. Structural variations in the lipid components of lipid A also occur. In addition, free lipid A is found at both 25 and 4 degrees C but not at 15 degrees C, which is the optimal growth temperature, suggesting a incomplete biosynthesis of the lipooligosaccharide component under the first two temperature conditions.

Antarctic Regions↗
PubMed2005

Characteristic fragmentation behavior of some glucuronide-type triterpenoid saponins using electrospray ionization tandem mass spectrometry.

The fragmentation behavior of some glucuronide-type triterpenoid saponins from Symplocos chinensis, and their analogues escin Ia and Ib, were investigated by positive ion electrospray ionization tandem mass spectrometry using a quadrupole linear ion trap mass spectrometer. The fragmentation patterns of these saponins significantly changed in accordance with structural variations in the glucuronyl residue of the oligosaccharide chain. It was found that the carboxyl group and hydroxyl group at the C-3' position of the glucuronyl residue were the key sites for determining the fragmentation behavior of these compounds. When the carboxyl group was esterified, only the C(2alpha) ion, and no B(2alpha) ion, and cationized aglycone were observed. When the hydroxyl group at C-3' was acylated, the inherent cross-ring cleavage was hindered. However, glycosidic cleavages always occurred, regardless of the crucial structural variations. The results of the present studies can benefit the determination of trace triterpenoid saponins of this type in crude plant extracts, and also provide background information to aid the structural investigations of similar glycoconjugates.

Escin↗
PubMed1981

A possible variant of thyroxine-binding globulin in Australian Aborigines.

We have recently described a major variation from the normal levels of serum thyroxine-binding globulin in many Australian Aborigines [1]. Subsequently we presented evidence that affected individuals were widely distributed throughout Australia, that "low values of thyroxine-binding globulin were not caused by environmental or health factors, but were inherited in an autosomal dominant fashion [2]. Refetoff [3] has shown that the cause of genetically determined low thyroxine-binding globulin levels in Caucasians is alteration in synthesis rate without any structural variation of the protein. Since however the "low" thyroxine-binding globulin of Aborigines is vastly more prevalent and genetically distinct from the X-linked type, we investigated the possibility that this may be a structural variant. Evidence suggestive of this includes results from heat inactivation, competitive binding of thyroxine to thyroxine-binding globulin to measure affinity, and use of a radioimmunoassay different from that used in the original work. The "Low thyroxine-binding globulin of Aborigines may be a protein with a structural variation at or near the binding site for thyroxine, resulting in low affinity for thyroxine and hence "low" results with assay methods which depend upon the thyroxine binding site. Since the Australoid peoples, to whom Australian Aborigines are racially related, are distributed widely throughout the southern hemisphere it is important to establish whether this variant is found outside Australia in order to avoid the likelihood of misdiagnosis of thyroid disease in such subjects.

Australia↗
PubMed1985

Structure and variation of the influenza C glycoprotein.

The amino acid sequence of the influenza C/JHB/1/66 glycoprotein was predicted from sequence analysis of cloned DNA. The glycoprotein exhibited several similarities to the haemagglutinin (HA) glycoproteins of influenza A and B viruses, although its overall homology to these glycoproteins was low. A comparison between the sequences of C/JHB/1/66 and C/Cal/78 strains revealed 96% homology. The nucleotide and amino acid changes appeared to be non-random, with a high proportion occurring between amino acid positions 182-212. A comparison between the JHB/1/66 glycoprotein and the influenza A/X31 HA sequence suggested that this region may be structurally analogous to the 'A' antigenic site of the HA glycoprotein.

Amino Acid Sequence↗
PubMed2025

Polyploidy-mediated variations in glutamate receptor proteins linked to Fusarium wilt resistance in upland cotton.

Cotton production in the US faces a serious threat from Fusarium oxysporum f. sp. vasinfectum race 4 (FOV4), a soil-borne fungus causing Fusarium wilt by infecting the roots and vascular system of susceptible cotton, leading to rapid wilting and death. Here, we investigate genetic mechanisms of resistance to FOV4 in the highly resistant upland cotton genotype "U1" using an early-generation segregating biparental population ("U1" × "CSX8308") with comprehensive genomic resources. Reference-grade genomic assemblies of the parents revealed minor structural variations between "U1" haplotypes, a high degree of collinearity at chromosome synteny and micro-synteny levels, and significant divergence from "CSX8308" with 8.9 million SNPs. QTL analysis identified significant markers on chromosomes D03 and A02 linked to reduced Fusarium wilt severity. Within these regions, two glutamate-receptor-like (GLR) genes showed structural variation and overlapped between translocated segments on A02 and D03, suggesting a rare but important reinforcing effect of parallel evolution between susceptible and resistant genotypes. Transcriptome profiles of "U1" under FOV4 infection reveal activation of calcium-binding proteins and transcription factors regulating plant hormones (ethylene, abscisic acid, jasmonic acid, and salicylic acid), along with enzymes involved in cell wall remodeling and phytoalexin production. Advancing cotton improvement depends on incorporating durable genetic disease resistance into high-yielding, high-quality cultivars.

Fusarium↗
PubMed2002

Evidence for facile atropisomerism and simple (non-nucleophilic) biradical-forming cycloaromatization within kedarcidin chromophore aglycon.

The kinetics and thermodynamics of atropisomerism within the protected kedarcidin chromophore aglycon 8, as well as a series of ansa-bridged synthetic intermediates leading to 8, were determined by 1H NMR spectroscopy. The data show that the ratio of atropisomeric forms of chloropyridine-bridged ansa intermediates is subject to wide variation with seemingly subtle structural variation. The vinyl bromide 4, for example, in the first X-ray structure determination of a kedarcidin ansa-bridged system, was found to exist as a single atropisomer in the solid state, but a nearly equal mixture (K = 0.70) of isomers in solution (t1/2 for isomer interconversion approximately 0.2 s at 20 degrees C). The aglycon 8, a 2.2:1 mixture of atropisomers, was found to undergo direct unimolecular biradical-forming cycloaromatization at ambient temperature in a mixture of 1,4-cyclohexadiene-benzene, without nucleophilic activation. The product 9 was formed as a single atropisomer (k = 2 x 10-4 s-1, t1/2 = 58 min, 81% yield), suggesting that the rate of atropisomerism within 8 is rapid with respect to cycloaromatization. The rate of cycloaromatization of 8 was found to be highly solvent-dependent, being more rapid in the presence of a good hydrogen-atom donor, consistent with the earlier model studies of Hirama et al. that showed that certain nine-membered cyclic (Z)-enediynes may equilibrate with their biradical cycloaromatization products. Incubation of 8 with beta-mercaptoethanol, under conditions mimicking experiments leading to DNA cleavage with kedarcidin, showed no evidence for nucleophilic activation. The product of direct cycloaromatization (9) was isolated instead. The evidence suggests that kedarcidin, like the enediyne agent C-1027, is capable of spontaneous thermal biradical formation without prior chemical activation.

Alkynes↗
PubMed2006

Protein Alpha Shape (PAS) Dock: a new gaussian-based score function suitable for docking in homology modelled protein structures.

Protein Alpha Shape (PAS) Dock is a new empirical score function suitable for virtual library screening using homology modelled protein structures. Here, the score function is used in combination with the geometry search method Tabu search. A description of the protein binding site is generated using gaussian property fields like in Protein Alpha Shape Similarity Analysis (PASSA). Gaussian property fields are also used to describe the ligand properties. The overlap between the receptor and ligand hydrophilicity and lipophilicity fields is maximised, while minimising steric clashes. Gaussian functions introduce a smoothing of the property fields. This makes the score function robust against small structural variations, and therefore suitable for use with homology models. This also makes it less critical to include protein flexibility in the docking calculations. We use a fast and simplified version of the score function in the geometry search, while a more detailed version is used for the final prediction of the binding free energies. This use of a two-level scoring makes PAS-Dock computationally efficient, and well suited for virtual screening. The PAS-Dock score function is trained on 218 X-ray structures of protein- ligand complexes with experimental binding affinities. The performance of PAS-Dock is compared to two other docking methods, AutoDock and MOE-Dock, with respect to both accuracy and computational efficiency. According to this study, PAS-Dock is more computationally efficient than both AutoDock and MOE-Dock, and gives a better prediction of the free energies of binding. PAS-Dock is also more robust against structural variations than AutoDock.

Algorithms↗
PubMed1994

Cell surface syndecan-1 on distinct cell types differs in fine structure and ligand binding of its heparan sulfate chains.

Heparan sulfate (HS) can bind a large variety of biological effectors, including extracellular matrix components, growth factors, chemokines, degradative enzymes, and protease inhibitors. Where studied, HS is known to be structurally heterogeneous and to vary in sulfation pattern between cells and tissues. Because heparan sulfate can represent several distinct proteoglycans, we asked whether the structural variation in the heparan sulfate chains of a single species of cell surface proteoglycan is a reproducible, differentiated characteristic and whether the variation can result in distinct biological functions. We studied the molecular structure and binding affinity for type I collagen and fibroblast growth factor-2 of syndecan-1 purified from the surfaces of NMuMG normal murine mammary gland epithelia, NIH/3T3 fibroblasts, and BALB/3T3 endothelioid cells. Syndecan-1 from these cell types varied in molecular mass largely due to variation in the length of the HS chains. Although the highly sulfated and N-acetylated domains in these HS chains were organized similarly, the number of highly sulfated domains differed. The disaccharide compositions were also similar except for reproducible and consistent differences in the amount of hexuronic acid-N-sulfated-6-O-sulfated glucosamine and 2-O-sulfated hexuronic acid-N-sulfated glucosamine. These differences were confirmed by oligosaccharide mapping, which showed cell type-specific variations in the composition of the highly sulfated domains. These structural variations correlated with cell type-specific differences in the affinity of syndecan-1 and its isolated HS chains for type I collagen. However, no differences in affinity for fibroblast growth factor-2 were detected. The results indicate that the size, fine structure, and ligand affinity of the HS chains on a single proteoglycan species differ in a consistent and reproducible manner between cell types. Thus, the variation in structure and binding ability of HS on syndecan-1 is a differentiated characteristic of the cell type that can enable cells to respond distinctly to the HS-binding effectors in the cellular microenvironment.

3T3 Cells↗
PubMedDate not supplied

Biotin reagents for antibody pretargeting. 4. Selection of biotin conjugates for in vivo application based on their dissociation rate from avidin and streptavidin.

An investigation was conducted to determine the affect of structural variation of biotin conjugates on their dissociation rates from Av and SAv. This information was sought to help identify optimal biotin derivatives for in vivo applications. Fifteen biotin derivatives were conjugated with a cyanocobalamin (CN-Cbl) derivative for evaluation of their "relative" dissociation rates by size exclusion HPLC analysis. Two biotin-CN-Cbl conjugates, one containing unaltered biotin and the other containing iminobiotin, were prepared as reference compounds for comparison purposes. The first structural variations studied involved modification of the biotinamide bond with a N-methyl moiety (i.e., sarcosine conjugate), lengthening the valeric acid side chain by a methylene unit (i.e., homobiotin), and replacing the biotinamide bond with thiourea bonds in two conjugates. The rate of dissociation of the biotin-CN-Cbl derivative from Av and SAv was significantly increased for biotin derivatives containing those structural features. Nine additional biotin conjugates were obtained by coupling amino acids or functional group protected amino acids to the biotin moiety. In the conjugates, the biotin moiety and biotinamide bond were not altered, but substituents of various sizes were introduced alpha to the biotinamide bond. The results obtained from HPLC analyses indicated that the rate of dissociation from Av or SAv was not affected by small substituents alpha to the biotinamide (e.g., methyl, hydroxymethyl, and carboxylate groups), but was significantly increased when larger functional groups were present. On the basis of the results obtained, it appears that biotin conjugates which retain an unmodified biotin moiety and have a linker molecule conjugated to it that has a small functional group (e.g., hydroxymethylene or carboxylate) alpha to the biotinamide bond are excellent candidates for in vivo applications. These structural features are obtained in the biotin amino acid conjugates: biotin-serine, biotin-aspartate, biotin-lysine, and biotin-cysteine. Importantly, these biotin derivatives can be readily conjugated with other molecules for specific in vivo applications. In our studies, these derivatives will be used in the design of new biotin conjugates to carry radionuclides for cancer therapy using the pretargeting approach.

Antibodies↗
PubMed1999

Transthyretin (prealbumin) in eye structures and variation of vitreous-transthyretin in diseases.

PURPOSE: To evaluate the presence of transthyretin (TTR, prealbumin) a protein which binds retinol to retinol-binding protein in various ocular tissues and to study its quantitative changes in the vitreous humor in various diseases. METHOD: Estimation of TTR was done by electrophoresis of 10 mg protein in each sample of tears, aqueous humor, vitreous, retina, and lens by an Imaging Densitometer using prealbumin as the standard. RESULTS: TTR was present in all the eye structures except the lens and tear. The retina and the vitreous had relatively higher amounts of TTR compared with aqueous. The identity of TTR was confirmed by immuno-electrophoresis using anti-human TTR. Two bands in SDS electrophoresis revealed that this protein is a heterodimer. There was a significant decrease in vitreous TTR in diabetes with hypertension and increase in one case each of diabetes with hypertension associated with leukaemia or carcinoma with hepato-splenomegaly. CONCLUSION: Vitreous TTR is probably from retina and retinal pigment epithelium. The level of vitreous TTR is likely to have diagnostic significance in some retinal diseases.

Adult↗
PubMed2001

Complex patterns of plastid 16S rRNA gene evolution in nonphotosynthetic green algae.

This study provides a phylogenetic/comparative approach to deciphering the processes underlying the evolution of plastid rRNA genes in genomes under relaxed functional constraints. Nonphotosynthetic green algal taxa that belong to two distinct classes, Chlorophyceae (Polytoma) and Trebouxiophyceae (Prototheca), were investigated. Similar to the situation described previously for plastid 16S rRNA genes in nonphotosynthetic land plants, nucleotide substitution levels, extent of structural variations, and percentage AT values are increased in nonphotosynthetic green algae compared to their closest photosynthetic relatives. However, the mutational processes appear to be different in many respects. First, with the increase in AT content, more transversions are noted in Polytoma and holoparasite angiosperms, while more transitions characterize the evolution of the 16S rDNA sequences in Prototheca. Second, although structural variations do accumulate in both Polytoma and Prototheca (as well as holoparasitic plastid 16S rRNAs), insertions as large as 1.6 kb characterize the plastid 16S rRNA genes in the former, whereas significantly smaller indels (not exceeding 24 bp) seem to be more prevalent in the latter group. The differences in evolutionary rates and patterns within and between lineages might be due to mutations in replication/repair-related genes; slipped-strand mispairing is likely the mechanism responsible for the expansion of insertions in Polytoma plastid 16S rRNA genes.

Chlorophyta↗
PubMed1998

Unusual and strongly structured sequence variation in a complex satellite DNA family from the nematode Meloidogyne chitwoodi.

An AluI satellite DNA family has been isolated in the genome of the root-knot nematode Meloidogyne chitwoodi. This repeated sequence was shown to be present at approximately 11,400 copies per haploid genome, and represents about 3.5% of the total genomic DNA. Nineteen monomers were cloned and sequenced. Their length ranged from 142 to 180 bp, and their A + T content was high (from 65.7 to 79.1%), with frequent runs of As and Ts. An unexpected heterogeneity in primary structure was observed between monomers, and multiple alignment analysis showed that the 19 repeats could be unambiguously clustered in six subfamilies. A consensus sequence has been deduced for each subfamily, within which the number of positions conserved is very high, ranging from 86.7% to 98.6%. Even though blocks of conserved regions could be observed, multiple alignment of the six consensus sequences did not enable the establishment of a general unambiguous consensus sequence. Screening of the six consensus sequences for evidence of internal repeated subunits revealed a 6-bp motif (AAATTT), present in both direct and inverted orientation. This motif was found up to nine times in the consensus sequences, also with the occurrence of degenerated subrepeats. Along with the meiotic parthenogenetic mode of reproduction of this nematode, such structural features may argue for the evolution of this satellite DNA family either (1) from a common ancestral sequence by amplification followed by mechanisms of sequence divergence, or (2) through independent mutations of the ancestral sequence in isolated amphimictic nematode populations and subsequent hybridization events. Overall, our results suggest the ancient origin of this satellite DNA family, and may reflect for M. chitwoodi a phylogenetic position close to the ancestral amphimictic forms of root-knot nematodes.

Animals↗
PubMed1994

Predicted stem-loop structures and variation in nucleotide sequence of 3' noncoding regions among animal calicivirus genomes.

Caliciviruses are nonenveloped with a polyadenylated genome of approximately 7.6 kb and a single capsid protein. The "RNA Fold" computer program was used to analyze 3'-terminal noncoding sequences of five feline calicivirus (FCV), rabbit hemorrhagic disease virus (RHDV), and two San Miguel sea lion virus (SMSV) isolates. The FCV 3'-terminal sequences are 40-46 nucleotides in length and 72-91% similar. The FCV sequences were predicted to contain two possible duplex structures and one stem-loop structure with free energies of -2.1 to -18.2 kcal/mole. The RHDV genomic 3'-terminal RNA sequences are 54 nucleotides in length and share 49% sequence similarity to homologous regions of the FCV genome. The RHDV sequence was predicted to form two duplex structures in the 3'-terminal noncoding region with a single stem-loop structure, resembling that of FCV. In contrast, the SMSV 1 and 4 genomic 3'-terminal noncoding sequences were 185 and 182 nucleotides in length, respectively. Ten possible duplex structures were predicted with an average structural free energy of -35 kcal/mole. Sequence similarity between the two SMSV isolates was 75%. Furthermore, extensive cloverleaflike structures are predicted in the 3' noncoding region of the SMSV genome, in contrast to the predicted single stem-loop structures of FCV or RHDV.

Base Sequence↗