E-, P-, and L-selectin counterreceptor activities, leukocyte trafficking, and lymphocyte homing are controlled prominently but incompletely by alpha(1,3)fucosyltransferase FucT-VII-dependent fucosylation. Molecular determinants for FucT-VII-independent leukocyte trafficking are not defined, and evidence for contributions by or requirements for other FucTs in leukocyte recruitment is contradictory and incomplete. We show here that inflammation-dependent leukocyte recruitment retained in FucT-VII deficiency is extinguished in FucT-IV(-/-)/FucT-VII(-/-) mice. Double deficiency yields an extreme leukocytosis characterized by decreased neutrophil turnover and increased neutrophil production. FucT-IV also contributes to HEV-born L-selectin ligands, since lymphocyte homing retained in FucT-VII(-/-) mice is revoked in FucT-IV(-/-)/FucT-VII(-/-) mice. These observations reveal essential FucT-IV-dependent contributions to E-, P-, and L-selectin ligand synthesis and to the control of leukocyte recruitment and lymphocyte homing.

Among mucus-secreting cells, the gastric gland mucous cells, Brunner's glands, accessory glands of pancreaticobiliary tract, and pancreatic ducts exhibiting gastric metaplasia are unique in that they express class III mucin identified by paradoxical Con A staining composed of periodate oxidation, sodium borohydride reduction, Con A, and horseradish peroxidase reaction. Recently it was shown that these mucous cells secrete glycoproteins having GlcNAc␣134Gal␤3R at nonreducing terminals of the carbohydrate moieties. Herein we describe the expression cloning of a cDNA encoding a human ␣1,4-N-acetylglucosaminyltransferase (␣4GnT), a key enzyme for the formation of GlcNAc␣134Gal␤13R. COS-1 cells were thus cotransfected with a stomach cDNA library and a leukosialin cDNA. Transfected COS-1 cells were screened by using monoclonal antibodies specific for GlcNAc␣134Gal␤3R and enriched by fluorescence-activated cell sorting. Sibling selection of recovered plasmids resulted in a cDNA clone that directs the expression of GlcNAc␣134Gal␤3R. The deduced amino acid sequence predicts a type II membrane protein with 340 amino acids, showing no significant similarity with any other proteins. The ␣4GnT gene is located at chromosome 3p14.3, and its transcripts are expressed in the stomach and pancreas. An in vitro GlcNAc transferase assay by using a soluble ␣4GnT revealed that ␣1,4-linked GlcNAc residues are transferred most efficiently to core 2 branched O-glycans (Gal␤13 4GlcNAc␤136(Gal␤133)GalNAc), forming GlcNAc␣13 4Gal␤134GlcNAc␤136(GlcNAc␣134Gal␤133)GalNAc. Transfection of ␣4GnT cDNA into gastric adenocarcinoma AGS cells produced class III mucin, indicating that ␣4GnT is responsible for the formation of class III Con A reactivity. These results indicate that the ␣4GnT is a glycosyltransferase that forms ␣1,4-linked GlcNAc residues, preferentially in O-glycans.

The North-eastern (NE) India, comprising of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura, possess diverse array of locally adapted non-Basmati aromatic germplasm. The germplasm collections from this region could serve as valuable resources in breeding for abiotic stress tolerance, grain yield and cooking/eating quality. To utilize such collections, however, breeders need information about the extent and distribution of genetic diversity present within collections. In this study, we report the result of population genetic analysis of 107 aromatic and quality rice accessions collected from different parts of NE India, as well as classified these accessions in the context of a set of structured global rice cultivars. A total of 322 alleles were amplified by 40 simple sequence repeat (SSR) markers with an average of 8.03 alleles per locus. Average gene diversity was 0.67. Population structure analysis revealed that NE Indian aromatic rice can be subdivided into three genetically distinct population clusters: P1, joha rice accessions from Assam, tai rices from Mizoram and those from Sikkim; P2, chakhao rice germplasm from Manipur; and P3, aromatic rice accessions from Nagaland. Pair-wise FST between three groups varied from 0.223 (P1 vs P2) to 0.453 (P2 vs P3). With reference to the global classification of rice cultivars, two major groups (Indica and Japonica) were identified in NE Indian germplasm. The aromatic accessions from Assam, Manipur and Sikkim were assigned to the Indica group, while the accessions from Nagaland exhibited close association with Japonica. The tai accessions of Mizoram along with few chakhao accessions collected from the hill districts of Manipur were identified as admixed. The results highlight the importance of regional genetic studies for understanding diversification of aromatic rice in India. The data also suggest that there is scope for exploiting the genetic diversity of aromatic and quality rice germplasm of NE India for rice improvement.

The SoxXAYZB(CD) -mediated pathway of bacterial sulfur-chemolithotrophy explains the oxidation of thiosulfate, sulfide, sulfur and sulfite but not tetrathionate. Advenella kashmirensis, which oxidizes tetrathionate to sulfate, besides forming it as an intermediate during thiosulfate oxidation, possesses a soxCDYZAXOB operon. Knock-out mutations proved that only SoxBCD is involved in A. kashmirensis tetrathionate oxidation, whereas thiosulfate-to-tetrathionate conversion is Sox independent. Expression of two glutathione metabolism-related proteins increased under chemolithotrophic conditions, as compared to the chemoorganotrophic one. Substrate-dependent oxygen consumption pattern of whole cells, and sulfur-oxidizing enzyme activities of cell-free extracts, measured in the presence/absence of thiol inhibitors/glutathione, corroborated glutathione involvement in tetrathionate oxidation. Furthermore, proteome analyses detected a sulfite:acceptor oxidoreductase (SorAB) exclusively under chemolithotrophic conditions, while expression of a methanol dehydrogenase (XoxF) homolog, subsequently named thiol dehydrotransferase (ThdT), was found to increase 3- and 10-fold during thiosulfate-to-tetrathionate conversion and tetrathionate oxidation respectively. A thdT knock-out mutant did not oxidize tetrathionate but converted half of the supplied 40 mM S-thiosulfate to tetrathionate. Knock-out of another thiosulfate dehydrogenase (tsdA) gene proved that both ThdT and TsdA individually converted ∼ 20 mM S-thiosulfate to tetrathionate. The overexpressed and isolated ThdT protein exhibited PQQ-dependent thiosulfate dehydrogenation, whereas its PQQ-independent thiol transfer activity involving tetrathionate and glutathione potentially produced a glutathione:sulfodisulfane adduct and sulfite. SoxBCD and SorAB were hypothesized to oxidize the aforesaid adduct and sulfite respectively.

BackgroundHill rices (Oryza sativa L.) are direct seeded rices grown on hill slopes of different gradients. These landraces have evolved under rainfed and harsh environmental conditions and may possess genes governing adaptation traits such as tolerance to cold and moisture stress. In this study, 64 hill rice landraces were collected from the state of Arunachal Pradesh of North-Eastern region of India, and assessed by agro-morphological variability and microsatellite markers polymorphism. Our aim was to use phenotypic and genetic diversity data to understand the basis of farmers’ classification of hill rice landraces into two groups: umte and tening. Another goal was to understand the genetic differentiation of hill rices into Indica or japonica subspecies.ResultsAccording to farmers’ classification, hill rices were categorized into two groups: umte (large-grained, late maturing) and tening (small-grained, early maturing). We did not find significant difference in days to 50 % flowering between the groups. Principal component analysis revealed that two groups can be distinguished on the basis of kernel length-to-width ration (KLW), kernel length (KL), grain length (GrL), grain length-to-width ration (GrLW) and plant height (Ht). Stepwise canonical discriminant analysis identified KL and Ht as the main discriminatory characters between the cultivar groups. Genetic diversity analysis with 35 SSR markers revealed considerable genetic diversity in the hill rice germplasm (gene diversity: 0.66; polymorphism information content: 0.62). Pair-wise allelic difference between umte and tening groups was not statistically significant. The model-based population structure analysis showed that the hill rices were clustered into two broad groups corresponding to Indica and Japonica. The geographic distribution and cultivars grouping of hill rices were not congruent in genetic clusters. Both distance- and model-based approaches indicated that the hill rices were predominantly japonica or admixture among the groups within the subspecies. These findings were further supported by combined analysis hill rices with 150 reference rice accessions representing major genetic groups of rice.ConclusionThis study collected a valuable set of hill rice germplasm for rice breeding and for evolutionary studies. It also generated a new set of information on genetic and phenotypic diversity of hill rice landraces in North-Eastern region of India. The collected hill rices were mostly japonica or admixture among the subpopulations of Indica or Japonica. The findings are useful for utilization and conservation of hill rice germplasm.Electronic supplementary materialThe online version of this article (doi:10.1186/s12863-016-0414-1) contains supplementary material, which is available to authorized users.

Poly-N-acetyllactosamines are attached to N-glycans, O-glycans, and glycolipids and serve as underlying glycans that provide functional oligosaccharides such as sialyl Lewis X . Poly-N-acetyllactosaminyl repeats are synthesized by the alternate addition of ␤1,3-linked GlcNAc and ␤1,4-linked Gal by i-extension enzyme (iGnT) and a member of the ␤1,4-galactosyltransferase (␤4Gal-T) gene family. In the present study, we first found that poly-N-acetyllactosamines in N-glycans are most efficiently synthesized by ␤4Gal-TI and iGnT. We also found that iGnT acts less efficiently on acceptors containing increasing numbers of N-acetyllactosamine repeats, in contrast to ␤4Gal-TI, which exhibits no significant change. In O-glycan biosynthesis, N-acetyllactosamine extension of core 4 branches was found to be synthesized most efficiently by iGnT and ␤4Gal-TI, in contrast to core 2 branch synthesis, which requires iGnT and ␤4Gal-TIV. Poly-N-acetyllactosamine extension of core 4 branches is, however, less efficient than that of N-glycans or core 2 branches. Such inefficiency is apparently due to competition between a donor substrate and acceptor in both galactosylation and N-acetylglucosaminylation, since a core 4-branched acceptor contains both Gal and GlcNAc terminals. These results, taken together, indicate that poly-N-acetyllactosamine synthesis in N-glycans and core 2-and core 4-branched Oglycans is achieved by iGnT and distinct members of the ␤4Gal-T gene family. The results also exemplify intricate interactions between acceptors and specific glycosyltransferases, which play important roles in how poly-Nacetyllactosamines are synthesized in different acceptor molecules.Poly-N-acetyllactosamines are unique glycans having N-acetyllactosamine repeats (Gal␤134GlcNAc␤133) n in one side chain (1). Poly-N-acetyllactosamines are attached to Nglycans (2-4), O-glycans (5-7), and glycolipids (8 -10). Poly-Nacetyllactosamines are often modified to express differentiation antigens and functional oligosaccharides. One of those oligosaccharides is sialyl Le X , 1 NeuNAc␣233Gal␤134(Fuc␣133)-GlcNAc3 R discovered in human granulocytes and monocytes (11,12). Sialyl Le X and its sulfated forms, such as 6-sulfo sialyl Le X , NeuNAc␣233Gal␤134[Fuc␣133(sulfo36)]GlcNAc3 R in mucin-type glycoproteins, have been shown to be ligands for E-, P-, and L-selectin (13-15).Since these O-glycans are present as clusters in mucin-type glycoproteins, mucin-type glycoproteins can present multiple ligands to a selectin. In mucin-type glycoproteins of blood cells, sialyl Le X can be found in core 2-branched oligosaccharides (5, 6, 16). Similarly, 6-sulfo sialyl Le X in L-selectin ligands found in high endothelial venules are synthesized in core 2-branched oligosaccharides such as NeuNAc␣233Gal␤134[Fuc␣133-(sulfo36)]GlcNAc␤136(Gal␤133)GalNAc␣13serine/threonine (17-19).The enzyme responsible for core 2 branching is called core 2 ␤1,6-N-acetylglucosaminyltransferase (C2GnT), and its cDNA has been cloned (20). When C2GnT was inactivated by gene targeting, leukocytes...

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Cigarette smoke (CS) causes oxidative damage and tea polyphenols have strong antioxidant properties. Therefore, we studied the effect of a black tea (BT) infusion on CS-induced oxidative damage of proteins both in vitro and in vivo. In the in vitro experiment, bovine serum albumin (BSA) or a guinea pig tissue microsomal suspension was incubated with an aqueous extract of CS (CS-solution) in the presence or absence of the BT infusion. Protein oxidation was measured by immunoblotting of the dinitrophenylhydrazone derivatives of the protein carbonyls followed by densitometric scanning. Protein degradation was assessed by SDS-PAGE. BT prevented (P < 0.05) CS-induced oxidation of BSA and oxidative degradation of guinea pig lung, liver and heart microsomal proteins. This was also observed when the BT infusion was replaced by its components, i.e, flavonols, theaflavins, thearubigins and catechins. BT prevented microsomal protein degradation by inhibiting oxidative modification of the proteins. The antioxidant effect of BT was similar to that of green tea. In the in vivo experiment, partially ascorbate-deficient guinea pigs were subjected to CS exposure from 5 cigarettes/(guinea pig. d) for 7 d and given water or the BT infusion (20 g/L) to drink. Guinea pigs exposed to CS and given water had extensive oxidation accompanied by 39, 40 and 30% losses (P < 0.05) of microsomal proteins of lung, liver and heart, respectively. However, when the CS-exposed guinea pigs consumed the BT infusion instead of water, the oxidation of microsomal proteins was reduced (P < 0.05) approximately 90, 97 and 70% in lung, liver and heart, respectively. Protein loss was reduced (P < 0.05) approximately 92, 98 and 90% in lung, liver and heart, respectively. The results, if extrapolated to humans, would indicate that regular intake of tea may protect smokers from CS-induced oxidative damage and consequent degenerative diseases.