Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.1 (sulfatase)
 3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

cDNAs encoding the human lysosomal hydrolase, arylsulfatase B (ASB; N-acetylgalactosamine-4-sulfatase, EC 3.1.6.1), were isolated from a hepatoma cell cDNA library using an ASB-specific oligonucleotide generated by the MOPAC (mixed oligonucleotide primed amplification of cDNA) technique. To facilitate cDNA cloning, human ASB was purified to apparent homogeneity and a total of 112 amino acid residues were microsequenced from the N-terminus and four internal tryptic peptides of the 47-kDa subunit. Based on the ASB N-terminal amino acid sequence, two oligonucleotide mixtures containing inosines to reduce the mixture complexity were constructed and used as primers to amplify an ASB-specific product from human placental cDNA by the polymerase chain reaction. DNA sequencing of this MOPAC product demonstrated colinearity with 21 N-terminal ASB amino acids. Based on this sequence and on codon usage for the adjacent conserved amino acids in human arylsulfatases A and C, a unique 66-mer was synthesized and used to screen a human hepatoma cell cDNA library. Four putative positive cDNA clones were isolated, and the largest insert (pASB-1) was sequenced in both orientations. The 1834-bp pASB-1 insert had a 1278-bp open reading frame encoding 425 amino acids that was colinear with 85 microsequenced amino acids of the purified enzyme, demonstrating its authenticity. Using the pASB-1 cDNA as a probe, a full-length cDNA clone, pASB-4, was isolated from a human testes library and sequenced in both orientations. pASB-4 had a 2811-bp insert containing a 559-bp 5' untranslated sequence, a 1602-bp open reading frame encoding 533 amino acids (six potential N-glycosylation sites), a 641-bp 3' untranslated sequence, and a 9-bp poly(A) tract. Comparison of the predicted amino acid sequences of arylsulfatases A, B, and C revealed regions of identity, particularly in their N-termini.
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PMID:Human arylsulfatase B: MOPAC cloning, nucleotide sequence of a full-length cDNA, and regions of amino acid identity with arylsulfatases A and C. 196 43

Membrane heparan sulfate proteoglycans (HSPG) regulate cell proliferation, migration, and differentiation and are therefore considered key players in cancer cell development processes. Here, we used the NT4 peptide to investigate how the sulfation pattern of HSPG on cells drives binding specificity. NT4 is a branched peptide that binds the glycosaminoglycan (GAG) chains of HSPG. It has already been shown to inhibit growth factor-induced migration and invasiveness of cancer cells, implying antagonist binding of HSPG. The binding affinity of NT4 with recombinant HSPG showed that NT4 bound glypican-3 and -4 and, with lower affinity, syndecan-4. NT4 binding to the cancer cell membrane was inversely correlated with sulfatase expression. NT4 binding was higher in cell lines with lower expression of SULF-1 and SULF-2, which confirms the determinant role of sulfate groups for recognition by NT4. Using 8-mer and 9-mer heparan sulfate (HS) oligosaccharides with analog disaccharide composition and different sulfation sites, a possible recognition motif was identified that includes repeated 6-O-sulfates alternating with N- and/or 2-O-sulfates. Molecular modeling provided a fully descriptive picture of binding architecture, showing that sulfate groups on opposite sides of the oligosaccharide can interact with positive residues on two peptide sequences of the branched structure, thus favoring multivalent binding and explaining the high affinity and selectivity of NT4 for highly sulfated GAGs. NT4 and possibly newly selected branched peptides will be essential probes for reconstructing and unraveling binding sites for cancer-involved ligands on GAGs and will pave the way for new cancer detection and treatment options.
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PMID:Unraveling Heparan Sulfate Proteoglycan Binding Motif for Cancer Cell Selectivity. 3162 Mar 57