Sequence analysis of the equine SLC26A2 gene locus on chromosome 14q15-->q21

The solute carrier family 26, member 2 (SLC26A2) gene belongs to a family of multifunctional anion exchangers. Mutations in the human SLC26A2 gene are associated with autosomal recessively inherited chondrodysplasias. Hence, we postulate that the equine SLC26A2 could be a candidate gene for conformational traits in horses. An equine BAC clone harboring the SLC26A2 gene was isolated. The complete 142,625 bp insert sequence of this clone was determined by transposon sequencing. Together with the SLC26A2 gene the BAC clone contains four genes, i.e. the macrophage colony stimulating factor 1 receptor precursor (CSF1R), KIAA0194 protein gene similar to the SMF protein (KIAA0194), a tigger transposable element derived 14 (TIGD14), the 3'-5'-cyclic GMP phosphodiesterase alpha-chain (EC 3.1.4.35) and one unidentified open reading frame. The equine SLC26A2 gene encompassing 6,152 bp consists of two exons. The complete open reading frame of 2,211 bp encodes a protein of 736 amino acids. A comparison of the amino acid sequence with other mammalian orthologs revealed homologies with identity in a range between 80% and 88%. By contrast, the equine SLC26A2 protein lacks five C-terminal amino acids. Four single nucleotide polymorphisms (SNP) were identified (three synonymous and one non-synonymous variant Ser210Leu) in the coding region by comparative sequencing of 50 DNA samples representing the German Riding horse. Allele frequencies and distribution were further evaluated in a variety of different breeds: Arabians (for all four SNPs), Old Kladrub Horses, Draught Horses (including Westphalian Draught Horses, Rheinish Westphalian Draught Horses, Saxon-Thuringia Coldbloods, Altmarker Coldbloods), American Saddlebreds, Miniature Horses, Australian Riding Ponies, Appaloosa, Morgan Horses, and Lipizzaner for C629T (Ser210Leu) alone. No animal carrying the homozygous genotype TT has been detected. The overall frequency of the newly described variant T is low (between 2% and 6%). Simulation studies on the protein conformation predict structural protein changes mediated by the SNP.     

Structure of equine 2'-5'oligoadenylate synthetase (OAS) gene family and FISH mapping of OAS genes to ECA8p15-->p14 and BTA17q24-->q25

Mammalian 2'-5' oligoadenylate (2-5A) synthetases are important mediators of the antiviral activity of interferons. Both human and mouse 2-5A synthetase gene families encode four forms of enzymes: small, medium, large and ubiquitin-like. In this study, the structures of four equine OAS genes were determined using DNA sequences derived from fifteen cDNA and four BAC clones. Composition of the equine OAS gene family is more similar to that of the human OAS family than the mouse Oas family. Two OAS-containing bovine BAC clones were identified in GenBank. Both equine and bovine BAC clones were physically assigned by FISH to horse and cattle chromosomes, ECA8p15-->p14 and BTA17q24--> q25, respectively. The comparative mapping data confirm conservation of synteny between ungulates, humans and rodents.     

New 11(15-->1)abeotaxane, 11(15-->1),11(10-->9)bisabeotaxane and 3,11-cyclotaxanes from Taxus yunnanensis

Chemical examination of the seeds of Chinese yew, Taxus yunnanensis Cheng et L. K. Fu resulted in the isolation of an 11(15-->1)abeotaxane, an 11(15-->1), 11(10-->9)bisabeotaxane and two 3,11-cyclotaxanes. The structures of these new taxoids were established as 13alpha-acetoxy-5alpha-cinnamoyloxy-11(15-->1)abeotaxa-4(20),11-diene-9alpha,10beta,15-triol (1), 20-acetoxy-2alpha-benzoyloxy-4alpha, 5alpha, 7beta, 9alpha, 13alpha-pentahydroxy-11(15-->1), 11(10-->9) bisabeotax-11-eno-10,15-lactone (2), 2alpha,10beta-diacetoxy-5alpha-cinnamoyloxy-9alpha-hydroxy-3,11 -cyclotax-4(20)-en-13-one (3) and 10beta-acetoxy-2alpha,5alpha,9alpha-trihydroxy-3,11-cyclotax-4(20)-en-13-one (4) on the basis of spectral analyses.     

An enzymatically produced novel cyclomaltopentaose cyclized from amylose by an alpha-(1-->6)-linkage, cyclo-{-->6)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->}

A bacterial strain AM7, isolated from soil and identified as Bacillus circulans, produced two kinds of novel cyclic oligosaccharides. The cyclic oligosaccharides were produced from amylose using a culture supernatant of the strain as the enzyme preparation. The major product was a cyclomaltopentaose cyclized by an alpha-(1-->6)-linkage, cyclo-{-->6)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->}. The other minor product was cyclomaltohexaose cyclized by an alpha-(1-->6)-linkage, cyclo-{-->6)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->}. We propose the names isocyclomaltopentaose (ICG5) and isocyclomaltohexaose (ICG6) for these novel cyclic maltooligosaccharides having one alpha-(1-->6)-linkage. ICG5 was digested by alpha-amylase derived from Aspergillus oryzae, cyclomaltodextrin glucanotransferase (CGTase) from Bacillus stearothermophilus, and maltogenic alpha-amylase. On the other hand, ICG6 was digested by CGTase from B. stearothermophilus and B. circulans, and maltogenic alpha-amylase. This is the first report of enzymatically produced cyclomaltopentaose and cyclomaltohexaose, which have an alpha-(1-->6)-linkage in their molecules.     

A jumping translocation (5p;15q), (8q;15q), and (12q;15q) (author's transl)]

Three balanced karyotypes (5p;15q), (8q;15q), and (12q;15q) were found simultaneously in a child with the Willi-Prader syndrome. The hypothesis is presented of a "jumping# translocation by affinity of telomeric and interstitial palindromes. The relationship between the Willi-Prader syndrome and a juxtacentric anomaly of the long arm of chromosome 15 is discussed.     

Synthesis of divalent beta-(1-->6)-branched (1-->3)-glucohexaose and trivalent beta-(1-->6)-branched (1-->3)-glucotriose

Hexaose, beta-D-Glcp-(1-->3)-[beta-D-Glcp-(1-->6)]-alpha-D-Glcp-(1-->3)-beta-D-Glcp-(1-->3)-[beta-D-Glcp-(1-->6)]-beta-D-Glcp, based dimers were synthesized by twofold glycosidation of the hexaosyl trichloroacetimidate with hexylene 1,6-diol, diethylene glycol and triethylene glycol, respectively. Meanwhile, a triose, beta-1D-Glcp-(1-->3)-[beta-D-Glcp-(1-->6)]-beta-D-Glcp, based trimer was obtained by glycosidation of the triosyl trichloroacetimidate with a glycerol-derived triol scaffold.     

An enzymatically produced novel cyclic tetrasaccharide, cyclo-{-->6)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->6)-alpha-D-Glcp-(1-->4)-alpha-D-Glcp-(1-->} (cyclic maltosyl-(1-->6)-maltose), from starch

A bacterial strain M6, isolated from soil and identified as Arthrobacter globiformis, produced a novel nonreducing oligosaccharide. The nonreducing oligosaccharide was produced from starch using a culture supernatant of the strain as enzyme preparation. The oligosaccharide was purified as a crystal preparation after alkaline treatment and deionization of the reaction mixture. The structure of the oligosaccharide was determined by methylation analysis, mass spectrometry, and (1)H and (13)C NMR spectroscopy, and it was demonstrated that the oligosaccharide had a cyclic structure consisting of four glucose residues joined by alternate alpha-(1-->4)- and alpha-(1-->6)-linkages. The cyclic tetrasaccharide, cyclo-{-->6)-alpha-D-Glcp(1-->4)-alpha-D-Glcp(1-->6)-alpha-D-Glcp(1-->4)-alpha-D-Glcp(1-->}, was found to be a novel oligosaccharide, and was tentatively called cyclic maltosyl-maltose (CMM). CMM was not hydrolyzed by various amylases, such as alpha-amylase, beta-amylase, glucoamylase, isoamylase, pullulanase, maltogenic alpha-amylase, and alpha-glucosidase, but hydrolyzed by isomalto-dextranase to give rise to isomaltose. This is the first report of the cyclic tetrasaccharide, which has alternate alpha-(1-->4)- and alpha-(1-->6)-glucosidic linkages.     

Identification of bound water molecules in the cyclic tetrasaccharide, cyclo-{-->6}-alpha-d-Glcp-(1-->3)-alpha-D-Glcp-(1-->6)-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->)

A structural characterization of bound water molecules in the cyclic tetrasaccharide, cyclo-{-->6}-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->6)-alpha-D-Glcp-(1-->3)-alpha-D-Glcp-(1-->), was carried out by NMR spectroscopy. H-1', 2'-OH, H-3', and 4'-OH of the 3-O-glycosylated residue and H-1 of the 6-O-glycosylated residue were found to cross-relax with protons of bound waters using the double-pulsed field-gradient spin-echo ROESY experiment. In the crystal structure, one water molecule is located in the center of the plate, and its temperature factor is very low, indicating that this water molecule is an intrinsic component.     

Synthesis of beta-D-Glcp-(1-->3)-[beta-D-Glcp-(1-->6)]-beta-D-Glcp-(1-->3)-beta-D-Glcp-(1-->6)-[beta-D-Galp-(1-->4)-beta-D-Glcp-(1-->3)]-beta-D-GlcpOLauryl, an oligosaccharide with anti-tumor activity

A concise and effective synthesis of lauryl heptasaccharide 17 was achieved from the key intermediates lauryl 2,3,4,6-tetra-O-benzoyl-beta-D-galactopyranosyl-(1-->4)-2,3,6-tri-O-benzoyl-beta-D-glucopyranosyl-(1-->3)-2,4-di-O-benzoyl-beta-D-glucopyranoside (10) and isopropyl 2,4,6-tri-O-acetyl-3-O-allyl-beta-D-glucopyranosyl-(1-->3)-[2,3,4,6-tetra-O-benzoyl-beta-D-glucopyranosyl-(1-->6)]-2,4-di-O-acetyl-beta-D-glucopyranosyl-(1-->3)-2,4,6-tri-O-acetyl-1-thio-beta-D-glucopyranoside (15). The key trisaccharide glycosyl acceptor 10 was constructed by coupling 2,3,4,6-tetra-O-benzoyl-beta-D-galactopyranosyl-(1-->4)-2,3,6-tri-O-benzoyl-alpha-D-glucopyranosyl trichloroacetimidate (3) with lauryl 6-O-acetyl-2,4-di-O-benzoyl-beta-D-glucopyranoside (9), followed by deacetylation. The thioglycoside donor 15 was obtained by condensation of 2,4,6-tri-O-acetyl-3-O-allyl-beta-D-glucopyranosyl-(1-->3)-[2,3,4,6-tetra-O-benzoyl-beta-D-glucopyranosyl-(1-->6)]-2,4-di-O-acetyl-alpha-D-glucopyranosyl trichloroacetimidate (11) with isopropyl 4,6-O-benzylidene-1-thio-beta-D-glucopyranoside (12), followed by debenzylidenation and acetylation. A bioassay of the inhibition of S180 noumenal tumors showed that lauryl heptasaccharide 17 could be employed as a potential agent for cancer treatment.     

Partial trisomy 14q due to maternal t(4;14)(p16;q32) in a dysmorphic newborn

Partial Trisomy 14q is a rare chromosomal disorder that mostly results from a parental translocation. We report here a newborn boy with partial trisomy 14q and dysmorphic features that are compatible with previously reported cases. Conventional cytogenetic analysis revealed an extra chromosomal segment at the end of the short arm of chromosome 4. In order to determine the origin of this chromosome region we used subtelomeric FISH technique. Based on the results of these cytogenetic studies and the physical examination, this dysmorphic case was diagnosed as partial trisomy of 14q and his karyotype determined as 46 XY, der(4)t(4;14)(p16;q32) resulting from a balanced maternal translocation identified as 46,XX, t(4;14)(p16;q32).     

Two familial cases with trisomy 15q dist due to a rcp(5;15)(p14;q21)

Summary A trisomy of the distal long arm of chromosome 15 (q21qter) resulting in similar phenotypic and developmental abnormalities in two related children (a boy and a girl) is described. The chromosome defect was due to malsegregation of a balanced translocation (5;15)(p14;q21) in one of the parents. It was inherited in four generations and accompanied by recurrent miscarriages. Comparison of these patients with four previously published cases of trisomy 15q dist reveals a pattern of common features including: microdolichocephaly with characteristic strikingly protuberant occiput and predominance of the visceral over the cerebral cranium; peculiar facial dysmorphism—narrow antimongoloid palpebral fissures; large, malformed, low-set ears; micrognathy; long philtrum; short neck; cardiopathy; profound encephalopathy with lack of suck and swallow reflexes; and no growth retardation.     

Partial trisomy 15q due to maternal translocation t(7;15)(q35;14)]

Partial trisomy for the long arm of chromosome 15 was detected in a 21-year-old girl with severe growth and mental retardation. A balanced reciprocal translocation - t(7;15)(q35;q14) - is present in the mother.