ricin B-type lectin domain, beta-trefoil fold; The ricin B-type lectin domain is a carbohydrate-binding domain formed from presumed gene triplication. It shows a beta-trefoil fold characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain was originally found in Ricin, which is a legume lectin from the seeds of the castor bean plant, Ricinus communis. It is also found in many carbohydrate-recognition proteins like plant and bacterial AB-toxins, glycosidases, or proteases, which serve diverse functions such as inhibitory toxicity, enzymatic activity, and signal transduction. The ricin B-type lectin domain can be present in one or more copies and has been shown in some instances to bind simple sugars, such as galactose or lactose. The most characteristic, though not completely conserved, sequence feature is the presence of a Q-W pattern. Consequently, the ricin B-type lectin domain has also been referred as the (QxW)3 domain and the three homologous regions as the QxW repeats. A disulfide bond is also conserved in some QxW repeats.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 796 PVVRASGVFINLALGKCVSIKNITVVLEDCDGSSELQQFNYTWVRLIKHGEWCVAPIPDKGSLTLYPCDNRNNRLKWLHR 875
Cdd:cd23436   1 PLVKASGLLVNVALRKCIAIENTTLTLQDCDLNNKSQHFNYTWLRLIRQGELCLAPVEAEGALTLHPCDNTNNGLRWLHK 80

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|...
gi 13929126 876 SASAFhPELVDHIVFESYQQLLCMEGNFSQKTLKLAACNPTEPQQKWKFEKYY 928
Cdd:cd23436  81 SLIAF-PELMDHIMLEHQSQPTCLEADPSQKILRLNACDSFKRYQKWRFGHYY 132

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 5 (GALNT5) and similar proteins; GALNT5 (EC 2.4.1.41), also called polypeptide GalNAc transferase 5, GalNAc-T5, pp-GaNTase 5, protein-UDP acetylgalactosaminyltransferase 5, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 5, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT5 has activity toward EA2 peptide substrate but has a weak activity toward Muc2 or Muc1b substrates. GALNT5 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 796 PVVRASGVFINLALGKCVSIKNITVVLEDCDGSSELQQFNYTWVRLIKHGEWCVAPIPDKGSLTLYPCDNRNNRLKWLHR 875
Cdd:cd23436   1 PLVKASGLLVNVALRKCIAIENTTLTLQDCDLNNKSQHFNYTWLRLIRQGELCLAPVEAEGALTLHPCDNTNNGLRWLHK 80

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|...
gi 13929126 876 SASAFhPELVDHIVFESYQQLLCMEGNFSQKTLKLAACNPTEPQQKWKFEKYY 928
Cdd:cd23436  81 SLIAF-PELMDHIMLEHQSQPTCLEADPSQKILRLNACDSFKRYQKWRFGHYY 132

Ricin-type beta-trefoil; Carbohydrate-binding domain formed from presumed gene triplication.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126    804 FINLALGKCVSIK--NITVVLEDCDGSSELQQFNYTWVRLIKH--GEWCVAPIPDKGS-LTLYPCDNRNNRLKWLHRSAS 878
Cdd:smart00458   1 IISGNTGKCLDVNgnKNPVGLFDCHGTGGNQLWKLTSDGAIRIkdTDLCLTANGNTGStVTLYSCDGTNDNQYWEVNKDG 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*....
gi 13929126    879 AFHpelvdhivfeSYQQLLCMEGNFSQK--TLKLAACNPTePQQKWKFE 925
Cdd:smart00458  81 TIR----------NPDSGKCLDVKDGNTgtKVILWTCSGN-PNQKWIFE 118

Ricin-type beta-trefoil lectin domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126   800 ASGVFINLALGKCVSI-----KNITVVLEDCDGSSELQQFNYTWVRLIKH--GEWC--VAPIPDKGSLTLYPCDNRNNRL 870
Cdd:pfam00652   1 ATGRIRNRASGKCLDVpggssAGGPVGLYPCHGSNGNQLWTLTGDGTIRSvaSDLCldVGSTADGAKVVLWPCHPGNGNQ 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 13929126   871 KWLHRSASafhpelvDHIVfeSYQQLLCME---GNFSQKTLKLAACNPTEPQQKW 922
Cdd:pfam00652  81 RWRYDEDG-------TQIR--NPQSGKCLDvsgAGTSNGKVILWTCDSGNPNQQW 126

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 5 (GALNT5) and similar proteins; GALNT5 (EC 2.4.1.41), also called polypeptide GalNAc transferase 5, GalNAc-T5, pp-GaNTase 5, protein-UDP acetylgalactosaminyltransferase 5, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 5, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT5 has activity toward EA2 peptide substrate but has a weak activity toward Muc2 or Muc1b substrates. GALNT5 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 796 PVVRASGVFINLALGKCVSIKNITVVLEDCDGSSELQQFNYTWVRLIKHGEWCVAPIPDKGSLTLYPCDNRNNRLKWLHR 875
Cdd:cd23436   1 PLVKASGLLVNVALRKCIAIENTTLTLQDCDLNNKSQHFNYTWLRLIRQGELCLAPVEAEGALTLHPCDNTNNGLRWLHK 80

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|...
gi 13929126 876 SASAFhPELVDHIVFESYQQLLCMEGNFSQKTLKLAACNPTEPQQKWKFEKYY 928
Cdd:cd23436  81 SLIAF-PELMDHIMLEHQSQPTCLEADPSQKILRLNACDSFKRYQKWRFGHYY 132

Ricin-type beta-trefoil; Carbohydrate-binding domain formed from presumed gene triplication.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126    804 FINLALGKCVSIK--NITVVLEDCDGSSELQQFNYTWVRLIKH--GEWCVAPIPDKGS-LTLYPCDNRNNRLKWLHRSAS 878
Cdd:smart00458   1 IISGNTGKCLDVNgnKNPVGLFDCHGTGGNQLWKLTSDGAIRIkdTDLCLTANGNTGStVTLYSCDGTNDNQYWEVNKDG 80

                           90       100       110       120
                   ....*....|....*....|....*....|....*....|....*....
gi 13929126    879 AFHpelvdhivfeSYQQLLCMEGNFSQK--TLKLAACNPTePQQKWKFE 925
Cdd:smart00458  81 TIR----------NPDSGKCLDVKDGNTgtKVILWTCSGN-PNQKWIFE 118

Ricin-type beta-trefoil lectin domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126   800 ASGVFINLALGKCVSI-----KNITVVLEDCDGSSELQQFNYTWVRLIKH--GEWC--VAPIPDKGSLTLYPCDNRNNRL 870
Cdd:pfam00652   1 ATGRIRNRASGKCLDVpggssAGGPVGLYPCHGSNGNQLWTLTGDGTIRSvaSDLCldVGSTADGAKVVLWPCHPGNGNQ 80

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 13929126   871 KWLHRSASafhpelvDHIVfeSYQQLLCME---GNFSQKTLKLAACNPTEPQQKW 922
Cdd:pfam00652  81 RWRYDEDG-------TQIR--NPQSGKCLDvsgAGTSNGKVILWTCDSGNPNQQW 126

Glycosyltransferase family A (GT-A) includes diverse families of glycosyl transferases with a common GT-A type structural fold; Glycosyltransferases (GTs) are enzymes that synthesize oligosaccharides, polysaccharides, and glycoconjugates by transferring the sugar moiety from an activated nucleotide-sugar donor to an acceptor molecule, which may be a growing oligosaccharide, a lipid, or a protein. Based on the stereochemistry of the donor and acceptor molecules, GTs are classified as either retaining or inverting enzymes. To date, all GT structures adopt one of two possible folds, termed GT-A fold and GT-B fold. This hierarchy includes diverse families of glycosyl transferases with a common GT-A type structural fold, which has two tightly associated beta/alpha/beta domains that tend to form a continuous central sheet of at least eight beta-strands. The majority of the proteins in this superfamily are Glycosyltransferase family 2 (GT-2) proteins. But it also includes families GT-43, GT-6, GT-8, GT13 and GT-7; which are evolutionarily related to GT-2 and share structure similarities.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 502 LLRSVHSVLNRSPPHLikEILLVDDFSTKDYLKAnLDKYMSQFPKVRILRLKERHGLIRARLAGAQNATGDVLTFLDSHV 581
Cdd:cd00761  12 LERCLESLLAQTYPNF--EVIVVDDGSTDGTLEI-LEEYAKKDPRVIRVINEENQGLAAARNAGLKAARGEYILFLDADD 88

                        90       100
                ....*....|....*....|...
gi 13929126 582 ECNVGWLEPLLERVYLNRKKVAC 604
Cdd:cd00761  89 LLLPDWLERLVAELLADPEADAV 111

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 7 (GALNT7) and similar proteins; GALNT7 (EC 2.4.1.41), also called polypeptide GalNAc transferase 7, GalNAc-T7, pp-GaNTase 7, protein-UDP acetylgalactosaminyltransferase 7, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 7, acts as glycopeptide transferase involved in O-linked oligosaccharide biosynthesis, which catalyzes the transfer of an N-acetyl-D-galactosamine residue to an already glycosylated peptide. In contrast to other proteins of the family, it does not act as a peptide transferase that transfers GalNAc onto serine or threonine residue on the protein receptor, but instead requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. Its appropriate peptide substrate remains unidentified. GALNT7 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 798 VRASGVFINLALGKCV----SIKNITVVLEDCDGSSELQQFNYTWVRLIKHGEWCVAPIPDKGSLTLYPCDNRNNRlKWL 873
Cdd:cd23437   2 NLAWGEIRNLGTGLCLdtmgHQNGGPVGLYPCHGMGGNQLFRLNEAGQLAVGEQCLTASGSGGKVKLRKCNLGETG-KWE 80

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
gi 13929126 874 HRSASafhpELVDHIVFEsyqqlLCMEGNFSQKTLKLAACNPTEPQQKWKF 924
Cdd:cd23437  81 YDEAT----GQIRHKGTG-----KCLDLNEGTNKLILQPCDSSSPSQKWEF 122

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 2 (GALNT2) and similar proteins; GALNT2 (EC 2.4.1.41), also called polypeptide GalNAc transferase 2, GalNAc-T2, pp-GaNTase 2, protein-UDP acetylgalactosaminyltransferase 2, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 2, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT2 has a broad spectrum of substrates for peptides such as EA2, Muc5AC, Muc1a, Muc1b. It is probably involved in O-linked glycosylation of the immunoglobulin A1 (IgA1) hinge region. It is also involved in O-linked glycosylation of APOC-III, ANGPTL3 and PLTP. It participates in the regulation of HDL-C metabolism. GALNT2 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 819 TVVLEDCDGSSELQQFNYTWVRLIKHGEWCVAPI-PDKGSL-TLYPCDNRNNRLKWLHRSASafhpelvDHIVFESYQql 896
Cdd:cd23434  22 TVGLYPCHGTGGNQEWSFTKDGQIKHDDLCLTVVdRAPGSLvTLQPCREDDSNQKWEQIENN-------SKLRHVGSN-- 92

                        90       100
                ....*....|....*....|....*....
gi 13929126 897 LCMEG-NFSQKTLKLAACNPTEPQQKWKF 924
Cdd:cd23434  93 LCLDSrNAKSGGLTVETCDPSSGSQQWKF 121

ricin B-type lectin domain, beta-trefoil fold, found in Drosophila melanogaster polypeptide N-acetylgalactosaminyltransferase 8 (Pgant8) and similar proteins; This subfamily includes Pgant8 (also called pp-GaNTase 8, protein-UDP acetylgalactosaminyltransferase 8, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 8), Pgant10 (also called polypeptide N-acetylgalactosaminyltransferase 10, pp-GaNTase 10, protein-UDP acetylgalactosaminyltransferase 10, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 10), Pgant11 (also called polypeptide N-acetylgalactosaminyltransferase 11, pp-GaNTase 11, protein-UDP acetylgalactosaminyltransferase 11, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 11) and Pgant12 (also called polypeptide N-acetylgalactosaminyltransferase 12, pp-GaNTase 12, protein-UDP acetylgalactosaminyltransferase 12, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 12). They function as GalNAc transferases (EC 2.4.1.41) that catalyze the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Pgant8 can both act as a peptide transferase that transfers GalNAc onto unmodified peptide substrates, and as a glycopeptide transferase that requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. It prefers both EA2 and the diglycosylated Muc5AC-3/13 as substrates, albeit at very low levels for Muc5AC-3/13. Members of this subfamily contain a ricin B-type lectin domain at the C-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain bears a potential sugar binding site.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 800 ASGVFINLAL-GKCVSIKNI----TVVLEDCDGS----SELQQFNYTWVRLIKHG--EWCVAPIPDkgSLTLYPCD-NRN 867
Cdd:cd23461   2 ASGVIQSVAFpNLCLDILGRshggPPVLAKCSSNksmpGTFQNFSLTFHRQIKHGtsDDCLEVRGN--NVRLSRCHyQGG 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 13929126 868 NRLkwlhrsasaFHPELVDHIVFESYQQLLCMEGNFSQKTLKLAACNPTEPQQKWKF 924
Cdd:cd23461  80 NQY---------WKYDYETHQLINGGQNNKCLEADVESLKITLSICDSDNVEQKWKW 127

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase 10 (GALNT10) and similar proteins; GALNT10 (EC 2.4.1.41), also called polypeptide GalNAc transferase 10, GalNAc-T10, pp-GaNTase 10, protein-UDP acetylgalactosaminyltransferase 10, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 10, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT10 has activity toward Muc5Ac and EA2 peptide substrates. GALNT10 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 796 PVVRASGVFINLALGKCVSIKNIT----VVLEDC----DGSS--ELQQFNYTWVRLIKHGE------WCVAPIPDKGSLT 859
Cdd:cd23476   2 PPAAAWGEIRNVGTGLCADTKHGAlgspLRLEGCvkgrGEAAwnNGQVFTFGWREDIRPGDpqhtkkFCFDAISHNSPVT 81

                        90       100       110       120       130       140
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 13929126 860 LYPCDNRNNRLKWLHRS-ASAFHPelvdhiVFESyqqllCMEGNFSQKTLKLAACNPTEPQQKWKFEK 926
Cdd:cd23476  82 LYDCHGMKGNQLWRYRKdKTLYHP------VSNS-----CMDCSESDHRIFMNTCNPSSPTQQWLFEH 138

ricin B-type lectin domain, beta-trefoil fold, found in polypeptide N-acetylgalactosaminyltransferase-like 6 (GALNTL6) and similar proteins; GALNTL6 (EC 2.4.1.41), also called polypeptide GalNAc transferase 17, GalNAc-T17, pp-GaNTase 17, protein-UDP acetylgalactosaminyltransferase 17, putative polypeptide N-acetylgalactosaminyltransferase 17, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 17, catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNTL6 comprises a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 796 PVVRASGVFINLALGKCVSIKN----ITVVLEDC--DGS----SELQQFNYTWVRLIKHGE------WCVAPIPDKGSLT 859
Cdd:cd23477   2 PPPAAWGEIRNVAANLCVDSKHgatgTELRLDICvkDGSertwSHEQLFTFGWREDIRPGEplhtrkFCFDAISHNSPVT 81

                        90       100       110       120       130       140
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 13929126 860 LYPCDNRNNRLKWLHRS-ASAFHPelvdhiVFESyqqllCMEGNFSQKTLKLAACNPTEPQQKWKFEK 926
Cdd:cd23477  82 LYDCHGMKGNQLWSYRKdKTLFHP------VSNS-----CMDCNPADKKIFMNRCDPLSETQQWIFEH 138

ricin B-type lectin domain, beta-trefoil fold, found in the macrophage mannose receptor (MRC) family; The MRC family includes MRC1-2, receptor-type tyrosine-protein phosphatase beta (PTPRB) isoform e, secretory phospholipase A2 receptor (PLA2R1), and lymphocyte antigen 75 (Ly-75). MRC1 mediates the endocytosis of glycoproteins by macrophages. It binds both sulfated and non-sulfated polysaccharide chains, and acts as a phagocytic receptor for bacteria, fungi, and other pathogens. It also acts as a receptor for Dengue virus envelope protein E. MRC2 may play a role as an endocytotic lectin receptor displaying calcium-dependent lectin activity. It internalizes glycosylated ligands from the extracellular space for release in an endosomal compartment via clathrin-mediated endocytosis. It may be involved in plasminogen activation system controlling the extracellular level of PLAUR/PLAU, and thus may regulate protease activity at the cell surface. It may contribute to cellular uptake, remodeling, and degradation of extracellular collagen matrices. It may play a role during cancer progression as well as in other chronic tissue destructive diseases acting on collagen turnover. It may participate in remodeling of extracellular matrix cooperating with the matrix metalloproteinases (MMPs). PTPRB (EC 3.1.3.48), also called protein-tyrosine phosphatase beta, plays an important role in blood vessel remodeling and angiogenesis. It is not necessary for the initial formation of the blood vessels but is essential for their maintenance and remodeling. It is also essential for the maintenance of endothelial cell contact integrity and for the adhesive function of VE-cadherin in endothelial cells that requires the presence of plakoglobin. PLA2R1 is a receptor for secretory phospholipase A2 (sPLA2). It acts as a receptor for phospholipase sPLA2-IB/PLA2G1B but not sPLA2-IIA/PLA2G2A. It can also bind to snake PA2-like toxins. It may be involved in responses in proinflammatory cytokine productions during endotoxic shock. It also has endocytic properties and rapidly internalizes sPLA2 ligands, which is particularly important for the clearance of extracellular sPLA2s to protect their potent enzymatic activities. Ly-75 acts as an endocytic receptor to direct captured antigens from the extracellular space to a specialized antigen-processing compartment. It causes reduced proliferation of B-lymphocytes. All family members contain a ricin B-type lectin domain at the N-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain may harbor a sugar-binding pocket. One member of this family, MRC1, is missing the gamma subdomain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 13929126 806 NLALGKCVSIKNIT--VVLEDCDGSSELQQFNYTWVRLIKHGEW--C--VAPIPDKGSLTLYPCDNRNNRLKW 872
Cdd:cd23385   7 NEDLGKCLAARSSSskVSLSTCNPNSPNQQWKWTSGHRLFNVGTgkClgVSSSSPSSPLRLFECDSEDELQKW 79

ricin B-type lectin domain, beta-trefoil fold, found in Drosophila melanogaster polypeptide N-acetylgalactosaminyltransferase 3 (Pgant3) and similar proteins; Pgant3, also called pp-GaNTase 3, protein-UDP acetylgalactosaminyltransferase 3, or UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 3, functions as a GalNAc transferase (EC 2.4.1.41) that catalyzes the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Pgant3 can both act as a peptide transferase that transfers GalNAc onto unmodified peptide substrates, and as a glycopeptide transferase that requires the prior addition of a GalNAc on a peptide before adding additional GalNAc moieties. It prefers EA2 as a substrate and has weak activity toward Muc5AC-3, -13 and -3/13 substrates. Pgant3 plays a critical role in the regulation of integrin-mediated cell adhesion during wing development by influencing, via glycosylation, the secretion and localization of the integrin ligand Tig to the basal cell layer interface. It may have a role in protein O-glycosylation in the Golgi and thereby in establishing and/or maintaining a proper secretory apparatus structure. Together with Pgant35A, Pgant3 regulates integrin levels and activity-dependent integrin signaling at the synapse in neurons and muscles. Members of this subfamily contain a ricin B-type lectin domain at the C-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain bears a potential sugar binding site.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 802 GVFINLALGKC-------VSIKNITvvLEDCDGSSELQQFNYTWVRLIKHGEWCVAPIPDKgSLTLYPCDNRNNRLKWLH 874
Cdd:cd23460   3 GQIKHTESGLCldwagesNGDKTVA--LKPCHGGGGNQFWMYTGDGQIRQDHLCLTADEGN-KVTLRECADQLPSQEWSY 79

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|
gi 13929126 875 RsasafhpELVDHIVFESYQqlLCMEGNFSQKTLKLAACNPTEPQQKWKF 924
Cdd:cd23460  80 D-------EKTGTIRHRSTG--LCLTLDANNDVVILKECDSNSLWQKWIF 120

DPM1_like represents putative enzymes similar to eukaryotic DPM1; Proteins similar to eukaryotic DPM1, including enzymes from bacteria and archaea; DPM1 is the catalytic subunit of eukaryotic dolichol-phosphate mannose (DPM) synthase. DPM synthase is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor, N-glycan precursor, protein O-mannose, and C-mannose. In higher eukaryotes,the enzyme has three subunits, DPM1, DPM2 and DPM3. DPM is synthesized from dolichol phosphate and GDP-Man on the cytosolic surface of the ER membrane by DPM synthase and then is flipped onto the luminal side and used as a donor substrate. In lower eukaryotes, such as Saccharomyces cerevisiae and Trypanosoma brucei, DPM synthase consists of a single component (Dpm1p and TbDpm1, respectively) that possesses one predicted transmembrane region near the C terminus for anchoring to the ER membrane. In contrast, the Dpm1 homologues of higher eukaryotes, namely fission yeast, fungi, and animals, have no transmembrane region, suggesting the existence of adapter molecules for membrane anchoring. This family also includes bacteria and archaea DPM1_like enzymes. However, the enzyme structure and mechanism of function are not well understood. This protein family belongs to Glycosyltransferase 2 superfamily.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 13929126 520 EILLVDDFSTKDYLKAnLDKYMSQFPKVRILRLKERHGLIRARLAGAQNATGDVLTFLD---SH 580
Cdd:cd06442  29 EIIVVDDNSPDGTAEI-VRELAKEYPRVRLIVRPGKRGLGSAYIEGFKAARGDVIVVMDadlSH 91

Subfamily of Glycosyltransferase Family GT2 of unknown function; GT-2 includes diverse families of glycosyltransferases with a common GT-A type structural fold, which has two tightly associated beta/alpha/beta domains that tend to form a continuous central sheet of at least eight beta-strands. These are enzymes that catalyze the transfer of sugar moieties from activated donor molecules to specific acceptor molecules, forming glycosidic bonds. Glycosyltransferases have been classified into more than 90 distinct sequence based families.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 490 IIMCFVDEVWSaLLRSVHSVLNRSPPHLIKEILLVDDFS---TKDYLKANLDKymsQFPKVRILRLKERH--GLIRARLA 564
Cdd:cd04192   1 VVIAARNEAEN-LPRLLQSLSALDYPKEKFEVILVDDHStdgTVQILEFAAAK---PNFQLKILNNSRVSisGKKNALTT 76

                        90       100       110       120       130
                ....*....|....*....|....*....|....*....|....*....|.
gi 13929126 565 GAQNATGDVLTFLDShvECNV--GWLEPLLERVYLNR-KKVACPVIEVIND 612
Cdd:cd04192  77 AIKAAKGDWIVTTDA--DCVVpsNWLLTFVAFIQKEQiGLVAGPVIYFKGK 125

ricin B-type lectin domain, beta-trefoil fold, found in the polypeptide N-acetylgalactosaminyltransferase 14 (GALNT14)-like subfamily; The GALNT14-like subfamily includes GALNT14 and GALNT16. They act as GalNAc transferases (EC 2.4.1.41) that catalyze the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. GALNT14 displays activity toward mucin-derived peptide substrates such as Muc2, Muc5AC, Muc7, and Muc13 (-58). It may be involved in O-glycosylation in the kidney. Members of this subfamily comprise a glycosyltransferase region and a ricin B-type lectin domain. The glycosyltransferase region contains two conserved domains, domain A (also called GT1 motif) and domain B (also called Gal/GalNAc-T motif). This model corresponds to the ricin B-type lectin domain with a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 820 VVLEDCDGSSELQQFNYTWVRLIKHGEWCVAPIPDKGSLTLY--PCdNRNNRLKWLHRSAsafhpelvdHIV-FESYqql 896
Cdd:cd23441  28 LILAPCSNSSDSQEWSFTKDGQLQTQGLCLTVDSSSKDLPVVleTC-SDDPKQKWTRTGR---------QLVhSESG--- 94

                        90       100
                ....*....|....*....|....*....
gi 13929126 897 LCMEgNFSQKTLKLAACNPTEPQQKWKFE 925
Cdd:cd23441  95 LCLD-SRKKKGLVVSPCRSGAPSQKWDFT 122

ricin B-type lectin domain, beta-trefoil fold, found in macrophage mannose receptor 1 (MRC1) and similar proteins; MRC1, also called MMR, C-type lectin domain family 13 member D (CLEC13D), C-type lectin domain family 13 member D-like (CLEC13DL), macrophage mannose receptor 1-like protein 1 (MRC1L1), or CD206, mediates the endocytosis of glycoproteins by macrophages. It binds both sulfated and non-sulfated polysaccharide chains. MRC1 acts as phagocytic receptor for bacteria, fungi and other pathogens. It also acts as a receptor for Dengue virus envelope protein E. MRC1 contains a ricin B-type lectin domain at the N-terminus. The ricin B-type lectin domain shows a beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry. Each subdomain may harbor a sugar-binding pocket.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 13929126 806 NLALGKCVSIKNITVV-LEDCDGSSELQQFnyTWV---RLIKHG-EWC--VAPIPDKGSLTLYPCDNRNNRLKWLHRSAS 878
Cdd:cd23407   7 NEDHNRCVQARSSSSVtTATCNPNAESQKF--RWVsgsQILSVAfKLClgVPSKKDWVTVTLFPCNEKSELQKWECKNDT 84

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*
gi 13929126 879 AFhpELVDHIVFESYqqllcmeGNFSQKTLKLaaCNPTEPQQKWK 923
Cdd:cd23407  85 LL--ALKGEDLYFNY-------GNRQEKNVML--YKGSGLWSRWK 118