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PubMed1991

DNA sequence analysis of NKG2, a family of related cDNA clones encoding type II integral membrane proteins on human natural killer cells.

We have previously described the isolation of a cDNA clone, designated NKG2, that was expressed in all natural killer (NK) cells tested but not in T or B cells. In the present communication, the original isolate, when used to probe a cDNA library prepared from a CD3- NK cell clone, was found to crosshybridize with a family of transcripts that fell into four distinct groups designated NKG2-A, -B, -C, and -D. Full-length cDNA sequences were determined for each group, and the DNA and inferred peptide sequences were analyzed. All four transcripts encode type II membrane proteins of 215-233 amino acids. NKG2-A and -B peptides appear to be alternative splicing products of a single gene. NKG2-C is highly homologous with group A, having 94% homology in the external (COOH-terminal) domain and 56% homology throughout the internal and transmembrane regions. NKG2-D is distantly but significantly related (21% amino acid homology) to the first three groups. Therefore, NKG2-A, -C, and -D appear to be encoded by distinct genes within a family of NK cell-specific genes. Peptide sequence homology searches demonstrate that the NKG2 peptides are members of a supergene family that includes several other type II membrane proteins. This family is characterized by the presence of a C-type animal lectin domain, and several of its members have demonstrated transmembrane signaling capability.

Amino Acid Sequence↗
PubMed1995

Human Mig chemokine: biochemical and functional characterization.

Mig is a chemokine of the CXC subfamily that was discovered by differential screening of a cDNA library prepared from lymphokine-activated macrophages. The mig gene is inducible in macrophages and in other cells in response to interferon (IFN)-gamma. We have transfected Chinese hamster ovary (CHO) cells with cDNA encoding human Mig and we have derived CHO cell lines from which we have purified recombinant human Mig (rHuMig). rHuMig induced the transient elevation of [Ca2+]i in human tumor-infiltrating T lymphocytes (TIL) and in cultured, activated human peripheral blood-derived lymphocytes. No responses were seen in human neutrophils, monocytes, or Epstein-Barr virus-transformed B lymphoblastoid cell lines. rHuMig was chemotactic for TIL by a modified Boyden chamber assay but rHuMig was not chemotactic for neutrophils or monocytes. The CHO cell lines, IFN-gamma-treated human peripheral-blood monocytes, and IFN-gamma-treated cells of the human monocytic cell line THP-1 all secreted multiple and identical HuMig species as revealed by SDS-PAGE. Using the CHO-derived rHuMig, we have shown that the species' heterogeneity is due to proteolytic cleavage at basic carboxy-terminal residues, and that the proteolysis occurs before and not after rHuMig secretion by the CHO cells. The major species of secreted rHuMig ranged from 78 to 103 amino acids in length, the latter corresponding to the full-length secreted protein predicted from the HuMig cDNA. Carboxy-terminal-truncated forms of rHuMig were of lower specific activity compared to full-length rHuMig in the calcium flux assay, and the truncated species did not block the activity of the full-length species. It is likely that HuMig plays a role in T cell trafficking and perhaps in other aspects of the physiology of activated T cells.

Amino Acid Sequence↗
PubMed1999

A new antigen recognized by cytolytic T lymphocytes on a human kidney tumor results from reverse strand transcription.

By stimulating blood lymphocytes from a renal cell carcinoma patient in vitro with the autologous tumor cells, we obtained cytolytic T lymphocyte (CTL) clones that killed several autologous and allogeneic histocompatibility leukocyte antigen (HLA)-B7 renal carcinoma cell lines. We identified the target antigen of these CTLs by screening COS cells transfected with the HLA-B7 cDNA and with a cDNA library prepared with RNA from the tumor cells. The antigenic peptide recognized by the CTLs has the sequence LPRWPPPQL and is encoded by a new gene, which we named RU2. This gene is transcribed in both directions. The antigenic peptide is not encoded by the sense transcript, RU2S, which is expressed ubiquitously. It is encoded by an antisense transcript, RU2AS, which starts from a cryptic promoter located on the reverse strand of the first intron and ends up on the reverse strand of the RU2S promoter, which contains a polyadenylation signal. This mechanism of antigen expression is unprecedented and further illustrates the notion that many peptides recognized by T cells cannot be predicted from the primary structure of the major product of the encoding gene. Antisense transcript RU2AS is expressed in a high proportion of tumors of various histological types. It is absent in most normal tissues, but is expressed in testis and kidney, and, at lower levels, in urinary bladder and liver. Short-term cultures of normal epithelial cells from the renal proximal tubule expressed significant levels of RU2AS message and were recognized by the CTLs. Therefore, this antigen is not tumor specific, but corresponds to a self-antigen with restricted tissue distribution.

Amino Acid Sequence↗
PubMed2002

Isolation and characterization of chicken interleukin-17 cDNA.

Interleukin-17 (IL-17) is a proinflammatory cytokine produced by activated T cells. A 917-bp cDNA encoding the IL-17 gene was isolated from our EST cDNA library prepared from intestinal intraepithelial lymphocytes (IELs) of Eimeria-infected chickens. It contained a 507-bp open reading frame (ORF) predicted to encode a protein of 169 amino acids (aa) with a molecular mass of 18.9 kDa, a 27-residue NH(2)-terminal signal peptide, a single potential N-linked glycosylation site, and 6 cysteine residues conserved with mammalian IL-17. Chicken IL-17 (chIL-17) shared 37%-46% amino acid sequence identity to the previously described mammalian homologs and also was homologous to the ORF 13 of Herpesvirus saimiri (HVS 13). By Northern blot analysis, IL-17 transcripts were identified in a reticuloendotheliosis virus (REV)-transformed chicken lymphoblast cell line (CU205) and conconavalin A (ConA)-stimulated splenic lymphocytes but not other chicken cell lines or normal tissues. Conditioned medium from COS-7 cells transfected with ChIL-17 cDNA induced IL-6 production by chicken embryonic fibroblasts, suggesting a functional role for the cytokine in avian immunity.

Amino Acid Sequence↗
PubMed1988

Regulation of alpha 2(I), alpha 1(III), and alpha 2(V) collagen mRNAs by estradiol in the immature rat uterus.

We show that mRNAs for alpha 2(I), alpha 1(III), and alpha 2(V) collagens are regulated by estradiol in the immature rat uterus. Clones for alpha 2(I) and alpha 1(III) collagen were induced in a cDNA library prepared from estradiol-stimulated rat uterine mRNA. Alpha 2(I) collagen cDNA was identified by its characteristic hybridization pattern on Northern blots and hybridization to known probes. The sequence of alpha 1(III) collagen cDNA showed 91% amino acid sequence homology with the corresponding 525-nucleotide segment of human alpha 1(III) procollagen cDNA. Type I and type III collagen mRNAs were coordinately regulated, and showed peaks of induction at 4 and 24 hr. Three injections of estradiol, 24 hr apart, produced induction maxima 24 hr apart. The third induction, however, was suppressed relative to the first, suggesting that estrogen-stimulated factors may act to negatively regulate the uterine response to estrogen.

Amino Acid Sequence↗
PubMed1989

Tilapia prolactin: molecular cloning of two cDNAs and expression in Escherichia coli.

We have isolated cDNA clones encoding tilapia prolactin (tiPRL) from a cDNA library prepared from tilapia (Oreochromis niloticus) anterior pituitary glands. A trout PRL cDNA fragment was used as hybridization probe to select the recombinant plasmids carrying the tiPRL coding sequence. Two types of PRL cDNA were isolated and their complete nucleotide sequence determined. The larger cDNA (tiPRL-I) codes for a polypeptide of 212 amino acids, including a putative signal sequence of 24 amino acids, and contains a 3' untranslated region of 787 bp. The second prolactin cDNA (tiPRL-II) encodes a polypeptide of 200 amino acids, including a presumptive signal peptide of 23 amino acids, and contains a noncoding region of 512 bp. tiPRL-I and tiPRL-II cDNA sequences are 81% similar, whereas the encoded proteins share 69% amino acid identity at optimal alignment. Mature tiPRL-I was efficiently expressed in Escherichia coli carrying a plasmid in which the tiPRL-I cDNA was under the control of the phi 10 promoter of T7 bacteriophage. The new recombinant protein representing about 45% of the total cellular proteins was found in inclusion bodies and cross-reacted with salmon PRL antiserum.

Amino Acid Sequence↗
PubMed1989

Structure of human angiotensinogen gene.

A cDNA clone encoding human angiotensinogen was isolated from a cDNA library prepared from human liver mRNA and used to isolate the angiotensinogen gene. The complete exon sequence of this gene together with extensive intron and flanking sequences are reported. The human angiotensinogen gene contains five exons interrupted by four intervening sequences. We compared the intron-exon structure of this human gene with that of the rat gene or the genes coding for proteins such as alpha 1-antitrypsin and antithrombin III, whose primary amino acid sequences show similarities. The human angiotensinogen gene shows identical organization with the alpha 1-antitrypsin gene, but is different from the antithrombin III gene. The 5'-flanking sequence (-500 to -1 bp) of the human angiotensinogen gene was examined for hormone regulatory elements (HRE), which may be implicated in the interaction with the hormone receptor complexes.

Amino Acid Sequence↗
PubMed1986

cDNA clones for liver cytochrome P-450s from individual aroclor-treated rats: constitutive expression of a new P-450 gene related to phenobarbital-inducible forms.

Differential hybridization and screening with cloned inserts was used to identify two families of cytochrome P-450 cDNA clones in libraries prepared from total liver poly(A)+RNA of individual Aroclor-treated rats. One family has cDNA inserts for the major phenobarbital-inducible P-450s, P-450b and P-450e. Two types of P-450e inserts were identified. In addition, irregular inserts were characterized from two clones (PB23 and PB24) of this group. The other family has cDNA inserts for the major 3-methylcholanthrene-inducible species, P-450c and P-450d. No coding sequence restriction site variants were detected among 26 P-450d and P-450c inserts analyzed. The restriction map of the irregular 2.2-kb PB23 insert has a P-450b-like portion, followed by a 3' extension that hybridizes to RNAs of 2.7 and 4.8 kb, which are also detectable with a classical P-450b probe. The PB23 insert and the 2.7- and 4.8-kb RNAs presumably represent 3' extensions of P-450b/P-450e mRNAs, polyadenylated at downstream sites. The 858-bp sequence of the PB24 insert encodes the carboxy-terminal portion of a P-450b/P-450e-like protein. There is approximately 20% divergence at the polypeptide level between the PB24 and P-450b/P-450e sequences; nevertheless, they share many essential features. A PB24-specific probe hybridizes to a 1.9-kb RNA species which is present in the liver of untreated rats and which is not appreciably induced by phenobarbital or Aroclor. The PB24 cDNA most likely represents a constitutive cytochrome P-450, related to phenobarbital-inducible forms.

Amino Acid Sequence↗
PubMed1987

Cloning and 5' end nucleotide sequences of two juvenile hormone-inducible vitellogenin genes of the African migratory locust.

Screening of lambda libraries prepared with locust (Locusta migratoria) genomic DNA yielded overlapping clones containing two complete vitellogenin genes, designated A and B, along with extensive 3'- and 5'-flanking sequences. Genes A and B are about 12 kb and 10.5 kb long, respectively, and both hybridize on Northern blots with 6300-nucleotide RNAs previously identified as vitellogenin mRNAs. Each gene contains a large intron near the 5' end and must also contain other introns. Repetitive "Lm1 elements," similar to the human Alu repetitive DNA elements, and other repeated sequences occur within the large intron and in the 3'- and 5'-flanking regions of each gene. Southern blots showed no cross-hybridization between the major portions of mRNA-coding sequences of genes A and B. DNA sequences have been determined for the 5' terminal exons and flanking regions of both genes. Both genes contain short (56-58 nucleotide) 5' leader exons, which, unlike the rest of the coding region, are highly conserved in sequence (87% identical) and code for amino acids that resemble the amino-terminal sequences of vertebrate vitellogenins. The upstream 5'-flanking sequences of the two genes contain several short stretches of similarity that may be involved in juvenile hormone regulated expression.

Animals↗
PubMed1990

A cDNA encoding a rat mitochondrial cytochrome P450 catalyzing both the 26-hydroxylation of cholesterol and 25-hydroxylation of vitamin D3: gonadotropic regulation of the cognate mRNA in ovaries.

A cDNA expression library prepared from rat liver RNA was screened with a polyclonal antibody specific for mitochondrial vitamin D3 25-hydroxylase and a cDNA for rabbit liver mitochondrial cytochrome P450c26 (CYP 26), yielding cDNA clones with identical sequences. The deduced amino acid sequence derived from a 1.9-kb full-length cDNA was 73% identical to that of rabbit cytochrome P450c26. A monoclonal antibody was used to demonstrate that the product of the 1.9-kb cDNA clone was targeted to the mitochondrial compartment when expressed in COS cells. Mitochondrial membranes containing the expressed protein showed both vitamin D3 25-hydroxylase and cholesterol 26-hydroxylase activities when reconstituted with ferredoxin reductase and ferredoxin, demonstrating that the same P450, designated as P450c26/25, can catalyze both reactions. Northern blot analysis revealed that the P450c26/25 cDNA hybridizes with a 2.4-kb RNA from rat liver and unstimulated ovaries. Treatment of rats with pregnant mare's serum gonadotropin resulted in a fivefold increase in the 2.4-kb mRNA as well as the appearance of a 2.1-kb mRNA species in the ovaries. Our findings document the presence of a regulated bifunctional mitochondrial cytochrome P450 capable of catalyzing the 25-hydroxylation of vitamin D3 and the 26-hydroxylation of cholesterol.

Amino Acid Sequence↗
PubMedDate not supplied

Characterization and expression of the prostatic arginine esterase gene, a canine glandular kallikrein.

The prostatic arginine esterase gene was isolated from a genomic library prepared with dog liver DNA in lambda EMBL3. The selected clone contained an insert of approximately 17 kb which included the whole coding portion of arginine esterase mRNA (5 exons plus 4 introns), 2 kb upstream from the initiation site and 12 kb downstream from the polyadenylation site. The intron-exon boundaries were identical to all known mammalian kallikrein genes. The deduced amino acid sequence indicated a high degree of identity (51-61%) with other kallikreins expressed not only in the prostate but also in the pancreas of various animal species. The 5'-flanking sequences contained potential regulatory elements such as a variant TATA box (TTTAAA), a CCAAT box, a SP1 transcriptional factor binding site (GGGCGG), and two TGTCCT motifs resembling glucocorticoid response elements. Southern blot analysis with an amplified cDNA fragment of 487 bp corresponding to the 5' portion of the mRNA and with a DNA probe from a different portion of the arginine esterase gene indicated the presence of two to three homologous genes in the canine genome while in a previous study a single band was detected using a 400-bp arginine esterase cDNA corresponding to the 3' portion of the mRNA. These results suggest that the arginine esterase gene belongs to a small kallikrein gene family. Arginine esterase mRNA is expressed primarily in the prostate but also at an extremely low level (approximately a thousandfold less) in several other tissues including the liver, the gracilis thigh muscle, the kidney, and the pancreas.

Animals↗
PubMed1994

A human gene encoding a putative basic helix-loop-helix phosphoprotein whose mRNA increases rapidly in cycloheximide-treated blood mononuclear cells.

G0S8 is a member of a set of putative G0/G1 switch regulatory genes (G0S genes) selected by screening cDNA libraries prepared from blood mononuclear cells cultured for 2 hr with lectin and cycloheximide. Comparison of a full-length cDNA sequence with the corresponding genomic sequence reveals an open reading frame of 211 amino acids, distributed across 5 exons. The 24-kD protein has a basic domain preceding a potential helix-loop-helix domain which contains a QTK motif found about 60 amino acids from the carboxyl terminus in the loop region of several helix-loop-helix proteins. There are potential phosphorylation sites for protein kinase C, creatine kinase II, and protein tyrosine kinases and regions of sequence similarity to helix-loop-helix proteins, tyrosine phosphatases, and RNA and DNA polymerases. The genomic sequence contains a CpG island, suggesting expression in the germ line. Potential binding sites for transcription factors are present in the 5' flank and introns; these include Zif268/NGFI-A/EGR1/G0S30, NGFI-B, Ap1, and factors that react with retroviral long terminal repeats (LTRs). There are several potential interferon response elements and a serum response element in the 3' flank overlapping a region of similarity to a cytomegalovirus immediate-early gene enhancer. Many of these motifs are found in immediate-early G0/G1 switch genes; however, we were unable to demonstrate an increase in G0S8 mRNA in response to lectin alone. Sequence similarities are noted between G0S8 and a variety of genes involved in the immune system, in the regulation of retroviruses, and in the cell cycle.

Amino Acid Sequence↗
PubMed1994

Cloning and characterization of hamster proenkephalin gene.

Our previous studies have shown that the hamster adrenal, like the human, contains high levels of preproenkephalin (PPenk) mRNA and enkephalin peptides, and may serve as a mammalian model for the in vivo study of proenkephalin (Penk) gene expression, peptide biosynthesis, and release. To define further the factors that may regulate hamster Penk gene expression, the hamster Penk gene was isolated from a genomic library prepared from Syrian hamster liver. The hamster Penk gene contains four exons and three introns and encodes 268 amino acids including six copies of Met-enkephalin containing peptides and one copy of Leu-enkephalin. In the 5' upstream region, there are TATA and GC boxes and multiple putative regulatory elements including the cAMP response element, AP-1, AP-2, AP-4, and the glucocorticoid response element (GRE). Possible GREs are also present in the introns. A comparison with the human and the rat Penk genes indicates that both the human and hamster Penk gene contain three introns, while the rat Penk gene has two introns. The intron missing from the rat Penk gene is short and separates the first and second exons of the hamster and human genes. In addition, the hamster and human genes share a region (100 bases) in the 5' upstream sequence that is 98% homologous. It is of interest that Penk gene expression is high in the adrenal medulla of both human and hamster, but is much lower in the rat. These homologous regions and the extra intron may contain regulatory features responsible for a high level of expression in the human and hamster adrenal medulla.

Animals↗
PubMed1996

Sequence analysis and expression in cultured lymphocytes of the human FOSB gene (G0S3).

G0S3 is a member of a set of putative G0/G1 switch regulatory genes (G0S genes) selected by screening cDNA libraries prepared from human blood mononuclear cells cultured for 2 hr with lectin and cycloheximide. The sequence shows high homology with the murine FOSB gene, which encodes a component of the AP1 transcriptional regulator. Comparison of cDNA and genomic sequences reveals a 4-exon structure characteristic of the FOS family of genes. Freshly isolated cells show high levels of FOSB/G0S3 and FOS/G0S7 mRNAs, which decline rapidly during incubation in culture medium. The kinetics of expression suggest that the high initial levels are caused by the isolation procedure, and do not reflect constitutive expression. In cells preincubated for a day, levels of FOS mRNA reach a maximum 20 min after the addition of lectin and decline to control levels over the next 3 hr. Levels of FOSB mRNA reach a maximum 40 min after the addition of lectin and decline to control levels over the next 6 hr. In freshly isolated cells, both FOS and FOSB mRNAs increase dramatically in response to the protein synthesis inhibitor cycloheximide. In preincubated cells, the cycloheximide response is decreased, especially in the case of FOSB. These differences in expression of FOS and FOSB suggest different roles and regulation. Regions of low base order-dependent stem-loop potential in the region of the gene are defined. These indicate where base order has been adapted for purposes other than stem-loop stability (e.g., encoding proteins or gene regulation). Regions of low potential in a 68.5-kb genomic segment containing the FOSB gene suggest that the potential may help locate genes in uncharted DNA sequences.

Adult↗
PubMed2005

Characterization of a novel class II bHLH transcription factor from the black widow spider, Latrodectus hesperus, with silk-gland restricted patterns of expression.

Members of the basic helix-loop-helix (bHLH) family are required for a number of different developmental pathways, including lymphopoiesis, myogenesis, neurogenesis, and sex determination. Screening a cDNA library prepared from silk-producing glands of the black widow spider, we have identified a new bHLH transcription factor named SGSF. Within the bHLH region, SGSF showed considerable conservation with other HLH proteins, including Drosophila melanogaster achaete and scute, as well as three HLH proteins identified by gene prediction programs. The expression pattern of SGSF was restricted to a subset of silk-producing glands, which include the tubuliform and major ampullate glands. SGSF was capable of binding an E-box element as a heterodimer with the E protein, E47, but was unable to bind this motif as a homodimer. SGSF was demonstrated to be a nuclear transcription factor capable of attenuating the transactivation of E47 homodimers in mammalian cells. SGSF represents the first example of a silk gland-restricted bHLH protein, and its expression pattern suggests that SGSF plays a role in regulating differentiation of cells in the spider that control silk gland formation or egg case silk gene expression.

Amino Acid Sequence↗
PubMed1994

Suppression of mitochondrial mRNA levels and mitochondrial function in cells responding to the anticellular action of interferon.

A lambda cDNA library prepared from polyadenylated RNA isolated from Daudi cells was differentially screened to isolate cDNAs that recognize mRNA whose levels are reduced following interferon (IFN) treatment. Southern blot and DNA sequence analysis of 20 cDNA clones that were isolated revealed that they represented mitochondrially encoded mRNAs for the following proteins: cytochrome c oxidase subunits II and III, ATPase 6, cytochrome b, and subunit 1 of the NADH dehydrogenase. Northern blot analysis employing these cDNAs and oligonucleotides generated to the remaining mitochondrially encoded mRNAs demonstrated that IFN-alpha treatment of Daudi cells mediates a time-dependent suppression of the level of all of the mitochondrially encoded mRNAs. Study of this IFN-mediated effect reveals that: (i) the suppression of the level of these mRNAs is dependent on protein synthesis, (ii) it can be observed to occur prior to any detectable effect on thymidine incorporation, (iii) the degree of suppression correlates with the sensitivity of the cells to the anticellular action of IFN, and (iv) the suppression of the level of these RNAs appears to result from an effect on the level of transcription rather than on the stability of these mRNAs. A study of the level of cellular respiration in IFN-treated Daudi cells reveals a clear suppression 3 h following IFN treatment.

Base Sequence↗
PubMed2000

Wpkci, encoding an altered form of PKCI, is conserved widely on the avian W chromosome and expressed in early female embryos: implication of its role in female sex determination.

Two W chromosome-linked cDNA clones, p5fm2 and p5fm3, were obtained from a subtracted (female minus male) cDNA library prepared from a mixture of undifferentiated gonads and mesonephroi of male or female 5-d (stages 26-28) chicken embryos. These two clones were demonstrated to be derived from the mRNA encoding an altered form of PKC inhibitor/interacting protein (PKCI), and its gene was named Wpkci. The Wpkci gene reiterated approximately 40 times tandemly and located at the nonheterochromatic end of the chicken W chromosome. The W linkage and the moderate reiteration of Wpkci were conserved widely in Carinatae birds. The chicken PKCI gene, chPKCI, was shown to be a single-copy gene located near the centromere on the long arm of the Z chromosome. Deduced amino acid sequences of Wpkci and chPKCI showed approximately 65% identity. In the deduced sequence of Wpkci, the HIT motif, which is essential for PKCI function, was absent, but the alpha-helix region, which was conserved among the PKCI family, and a unique Leu- and Arg-rich region, were present. Transcripts from both Wpkci and chPKCI genes were present at significantly higher levels in 3- to 6-d (stages 20-29) embryos. These transcripts were detected in several embryonic tissues, including undifferentiated left and right gonads. When the green fluorescent protein-fused form of Wpkci was expressed in male chicken embryonic fibroblast, it was located almost exclusively in the nucleus. A model is presented suggesting that Wpkci may be involved in triggering the differentiation of ovary by interfering with PKCI function or by exhibiting its unique function in the nuclei of early female embryos.

Amino Acid Sequence↗
PubMed2001

Enhanced 3-O-sulfation of galactose in Asn-linked glycans and Maackia amurensis lectin binding in a new Chinese hamster ovary cell line.

We report the characterization of two Chinese hamster ovary cell lines that produce large amounts of sulfated N-linked oligosaccharides. Clones 26 and 489 were derived by stable transfection of the glycosaminoglycan-deficient cell mutant pgsA-745 with a cDNA library prepared from wild-type cells. Peptide:N-glycanase F released nearly all of the sulfate label, indicating that sulfation had occurred selectively on the Asn-linked glycans. Hydrazinolysis followed by nitrous acid treatment at pH 4 and borohydride reduction yielded reduced sulfated disaccharides that comigrated with standard Gal3SO4beta1-4anhydromannitol. The disaccharides were resistant to periodate oxidation but became sensitive after the sulfate group was removed by methanolysis, indicating that the sulfate was located at C3 of the galactose residues. Maackia amurensis lectin bound to the sulfated glycopeptides on the cell surface and in free form, even after sialidase treatment. This finding indicates that the lectin requires only a charged group at C3 of the galactose unit and not an intact sialic acid. Growth of cells with chlorate restored sialidase sensitivity to lectin binding, indicating that sulfation and sialylation occurred largely at the same sites. The enhanced sulfation was due to elevated sulfotransferase activity that catalyzed transfer of sulfate from phosphoadenosine-5'-phosphosulfate to Galbeta1-4(3)GlcNAcbeta-O-naphthalenemethanol.

Animals↗