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11.
Peteris Prusis Staffan Uhlén Ramona Petrovska Maris Lapinsh Jarl ES Wikberg 《BMC bioinformatics》2006,7(1):167-13
Background
Both direct and indirect interactions determine molecular recognition of ligands by proteins. Indirect interactions can be defined as effects on recognition controlled from distant sites in the proteins, e.g. by changes in protein conformation and mobility, whereas direct interactions occur in close proximity of the protein's amino acids and the ligand. Molecular recognition is traditionally studied using three-dimensional methods, but with such techniques it is difficult to predict the effects caused by mutational changes of amino acids located far away from the ligand-binding site. We recently developed an approach, proteochemometrics, to the study of molecular recognition that models the chemical effects involved in the recognition of ligands by proteins using statistical sampling and mathematical modelling. 相似文献12.
Patrick Solverson Sangita G. Murali Suzanne J. Litscher Robert D. Blank Denise M. Ney 《PloS one》2012,7(9)
Purpose
Phenylketonuria (PKU), caused by phenylalanine (phe) hydroxylase loss of function mutations, requires a low-phe diet plus amino acid (AA) formula to prevent cognitive impairment. Glycomacropeptide (GMP), a low-phe whey protein, provides a palatable alternative to AA formula. Skeletal fragility is a poorly understood chronic complication of PKU. We sought to characterize the impact of the PKU genotype and dietary protein source on bone biomechanics.Procedures
Wild type (WT; Pah+/+) and PKU (Pahenu2/enu2) mice on a C57BL/6J background were fed high-phe casein, low-phe AA, and low-phe GMP diets between 3 to 23 weeks of age. Following euthanasia, femur biomechanics were assessed by 3-point bending and femoral diaphyseal structure was determined. Femoral ex vivo bone mineral density (BMD) was assessed by dual-enengy x-ray absorptiometry. Whole bone parameters were used in prinicipal component analysis. Data were analyzed by 3-way ANCOVA with genotype, sex, and diet as the main factors.Findings
Regardless of diet and sex, PKU femora were more brittle, as manifested by lower post-yield displacement, weaker, as manifested by lower energy and yield and maximal loads, and showed reduced BMD compared with WT femora. Four principal components accounted for 87% of the variance and all differed significantly by genotype. Regardless of genotype and sex, the AA diet reduced femoral cross-sectional area and consequent maximal load compared with the GMP diet.Conclusions
Skeletal fragility, as reflected in brittle and weak femora, is an inherent feature of PKU. This PKU bone phenotype is attenuated by a GMP diet compared with an AA diet. 相似文献13.
Purified mouse egg zona pellucida glycoproteins polymerize into homomeric fibrils under non-denaturing conditions 总被引:1,自引:0,他引:1
The mouse egg's zona pellucida (ZP) is composed of three glycoproteins, called ZP1, ZP2, and ZP3, that migrate as relatively broad, single bands on SDS-PAGE. The glycoproteins are organized within the ZP as a network of long interconnected fibrils that exhibit a structural periodicity. Here, ZP2 and ZP3 were purified by HPLC to homogeneity and analyzed by Blue Native- (BN-) PAGE and transmission electron microscopy (TEM), as well as by SDS-PAGE. As opposed to SDS-PAGE, BN-PAGE, and TEM permit analysis of ZP2 and ZP3 under non-denaturing conditions. ZP2 and ZP3 migrate on BN-PAGE, not as single bands, but as several discrete oligomers that give rise to larger structures which remain at the origin of the gel. Consistent with this, ZP2 and ZP3 are visualized by TEM as long interconnected fibrils that consist of contiguous beads. Therefore, under non-denaturing conditions both purified ZP2 and ZP3 polymerize into higher order structures. These findings are of interest since purified ZP3 inhibits binding of mouse sperm to eggs and induces sperm to undergo the acrosome reaction in vitro. Results presented here suggest that these biological effects of ZP3 are due to binding of homomeric fibrils of ZP3 to sperm. 相似文献
14.
G Litscher W Nemetz J Smolle G Schwarz D Schikora S Uranüs 《Biomedizinische Technik》2004,49(1-2):2-5
In an experimental animal study (Sus scrofa domesticus) we investigated the effects of the new technique of laser needle stimulation (wavelength: 685 nm; energy density: 4.6 kJ/cm2 per point; application duration: 20 min). The results revealed changes in microcirculatory parameters of the skin resulting in an increase in blood flow. However, the quality and intensity of the laser light did not induce micromorphological alterations in the skin. 相似文献
15.
Mouse zona pellucida glycoproteins mZP2 and mZP3 undergo carboxy-terminal proteolytic processing in growing oocytes. 总被引:4,自引:0,他引:4
The extracellular coat, or zona pellucida, of the mouse egg consists of three glycoproteins, called mZP1-3. The glycoproteins are synthesized and secreted concomitantly by growing oocytes during their 2-3-week growth phase. Each of the glycoproteins has a consensus furin cleavage site (-Arg-X-Lys/Arg-Arg-) near the C-terminus of their polypeptide. Here, several approaches were employed to determine whether nascent mZP2 and mZP3 are cleaved at the consensus sites, -Arg-Ser-Lys-Arg- and -Arg-Asn-Arg-Arg-, respectively, prior to secretion. Molecular mass determinations of deglycosylated mZP2 and mZP3 suggest that their polypeptides are approximately 9 and approximately 7 kDa smaller, respectively, than predicted from exon sequences. Two-dimensional thin-layer chromatographic analyses were also carried out to identify amino acids released from the C-terminus of mZP2 and mZP3 by carboxypeptidase B. On the basis of exon sequences, there are no Arg residues at the predicted C-terminus of the mature glycoproteins. However, for both mZP2 and mZP3, Arg residues were released by carboxypeptidase B, consistent with processing at the consensus furin cleavage site. Furthermore, an antiserum raised against an mZP3 peptide, located downstream of the consensus furin cleavage site, failed to label purified mZP3 on Western immunoblots. The antiserum also failed to label the zona pellucida of oocytes examined by laser scanning confocal microscopy. Collectively, these results strongly suggest that mZP2 and mZP3 are processed at their consensus furin cleavage site prior to secretion and incorporation into the zona pellucida. 相似文献
16.
HEYO VAN ITEN JULIANA DE MORAES LEME† SABRINA COELHO RODRIGUES† MARCELLO GUIMARÃES SIMÕES‡ 《Palaeontology》2005,48(3):619-622
Abstract: Vendoconularia triradiata Ivantsov and Fedonkin, recently described from Vendian (latest Proterozoic) strata of Russia, has been interpreted as a six-sided conulariid cnidarian. However, comparison of published illustrations of V . triradiata with Palaeozoic conulariids suggests that certain key features of the anatomy of V . triradiata should be reinterpreted. Specifically, features previously homologized with the corners of conulariid thecae may actually be homologous to the conulariid midlines. Under this new interpretation, the corners of the Vendoconularia theca were sulcate, and the midline of each face was non-sulcate and flanked by a pair of low internal carinae. This alternative set of hypotheses of homology makes the argument for a conulariid affinity for Vendoconularia stronger. 相似文献
17.
JULIANA DE MORAES LEME MARCELLO GUIMARÃES SIMÕES ANTONIO CARLOS MARQUES† HEYO VAN ITEN‡ 《Palaeontology》2008,51(3):649-662
Abstract: Results of a cladistic analysis of the suborder Conulariina Miller and Gurley, 1896, a major extinct (Vendian–Triassic) group of scyphozoan cnidarians, are presented. The analysis sought to test whether the three conulariid subfamilies (Conulariinae Walcott, 1886 , Paraconulariinae Sinclair, 1952 and Ctenoconulariinae Sinclair, 1952 ) recognized in the Treatise on Invertebrate Paleontology (TIP) are monophyletic. A total of 17 morphological characters were scored for 16 ingroup taxa, namely the genera Archaeoconularia, Baccaconularia, Climacoconus, Conularia, Conulariella, Conularina, Ctenoconularia, Eoconularia, Glyptoconularia, Metaconularia, Notoconularia, Paraconularia, Pseudoconularia, Reticulaconularia, Teresconularia and Vendoconularia. The extant medusozoan taxa Cubozoa, Stauromedusae, Coronatae and Semaeostomeae served as outgroups. Unweighted analysisof the data matrix yielded 1057 trees, and successive weighting analysis resulted in one of the 1057 original trees. The ingroup is monophyletic with two autapomorphies: (1) the quadrate geometry of the oral region; and (2) the presence of a mineralized (phosphatic) periderm. Within the ingroup, the clade (Vendoconularia, Teresconularia, Conularina, Eoconularia) is supported by the sinusoidal longitudinal geometry of the transverse ridges, and the much larger clade (Baccaconularia, Glyptoconularia, Metaconularia, Pseudoconularia, Conularia, Ctenoconularia, Archaeoconularia, Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the presence of external tubercles, which, however, were lost in the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia). As proposed by Van Iten et al. (2000) , the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the termination and alternation of the transverse ribs in the corner sulcus. The previously recognized subfamilies Conulariinae, Paraconulariinae and Ctenoconulariinae were not recovered from this analysis. The diagnostic features of Conulariinae (continuation of the transverse ornament across the corner sulcus and lack of carinae) and Ctenoconulariinae (presence of carinae) are symplesiomorphic or homoplastic, and Paraconulariinae is polyphyletic. The families Conulariellidae Kiderlen, 1937 and Conulariopsidae Sugiyama, 1942 , also recognized in the TIP, are monogeneric, and since they provide no additional phylogenetic information, should be abandoned. 相似文献
18.
Katherine ES Lindhe Danny S Meldgaard Per M Jensen Geoffrey A Houser Mette Berendt 《Acta veterinaria Scandinavica》2009,51(1):56
Background
Large regions of central and eastern Europe are recognized as areas where tick-borne encephalitis virus (TBEV) is endemic, including countries neighbouring Denmark. It is therefore timely and relevant to determine if TBEV infections occur in Denmark. This study investigates the presence of antibodies against TBEV in a cross-section of the Danish canine population to assess the level of exposure to TBEV and possibly identify TBEV microfoci in Denmark. 相似文献19.
Relationships among msx gene structure and function in zebrafish and other vertebrates 总被引:6,自引:2,他引:4
Ekker M; Akimenko MA; Allende ML; Smith R; Drouin G; Langille RM; Weinberg ES; Westerfield M 《Molecular biology and evolution》1997,14(10):1008-1022
The zebrafish genome contains at least five msx homeobox genes, msxA, msxB,
msxC, msxD, and the newly isolated msxE. Although these genes share
structural features common to all Msx genes, phylogenetic analyses of
protein sequences indicate that the msx genes from zebrafish are not
orthologous to the Msx1 and Msx2 genes of mammals, birds, and amphibians.
The zebrafish msxB and msxC are more closely related to each other and to
the mouse Msx3. Similarly, although the combinatorial expression of the
zebrafish msx genes in the embryonic dorsal neuroectoderm, visceral arches,
fins, and sensory organs suggests functional similarities with the Msx
genes of other vertebrates, differences in the expression patterns preclude
precise assignment of orthological relationships. Distinct duplication
events may have given rise to the msx genes of modern fish and other
vertebrate lineages whereas many aspects of msx gene functions during
embryonic development have been preserved.
相似文献
20.
RICARDO BONFIM-SILVA LARISSA OLIVEIRA GUIMARÃES JANDSON SOUZA SANTOS JAQUELINE FAGUNDES PEREIRA ANA ANGÉLICA LEAL BARBOSA DOMINGOS LAZARO SOUZA RIOS 《Journal of genetics》2016,95(1):63-69
The rennin–angiotensin–aldosterone system (RAAS) is a critical pathway in regulating blood pressure and salt/water homeostasis, possessing an intimate relationship with the development of systemic artery hypertension (SAH). Once hypertension is considered a risk factor for coronary artery disease (CAD), the RAAS is also related to this pathology. This investigation aimed to analyse if the frequencies of AGT M235T (rs699) and ACE I/D (rs4646994) polymorphisms are associated with CAD and SAH in African-Brazilians and Caucasian-Brazilians. In this study we analysed 714 subjects who underwent coronary angiography to detect obstructive lesions and CAD, as well as blood pressure measurement and SAH, grouped according to ethnicity: 266 African-Brazilians and 448 Caucasian-Brazilians. Among CAD and SAH cases and controls, the genotype and allele frequencies of ACE I/D polymorphism were similar in both ethnic groups. The AGT 235TT genotype and 235T allele frequencies were higher in SAH cases (32%, 54.7%) versus controls in Caucasian-Brazilians (19.8%, 46.4%; P= 0.038, P= 0.031, respectively). The AGT 235TT (OR = 1.8; P= 0.028) demonstrated to be an independent factor risk in a multivariate logistic regression increasing SAH risk in Caucasians but not in African-Brazilians. In summary, AGT M235T polymorphism was associated with SAH risk in Caucasian-Brazilians, and no association was detected with CAD. No association was also observed in ACE I/D polymorphism either in CAD or SAH in African-Brazilians and Caucasian-Brazilians. 相似文献