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Bernard De Geus - One of the best experts on this subject based on the ideXlab platform.
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llama heavy chain v regions consist of at least four distinct subfamilies revealing novel sequence features
Molecular Immunology, 2000Co-Authors: M M Harmsen, Leon G J Frenken, Robin C Ruuls, Isaac J Nijman, Theodoor Niewold, Bernard De GeusAbstract:In addition to conventional antibodies (Abs), Camelids possess Abs consisting of only heavy chains. The variable domain of such a heavy-chain Ab (VHH) is fully capable of antigen (Ag) binding. Earlier analysis of 47 VHHs showed sequence features unique to VHH domains. These include the presence of characteristic amino acid substitutions in positions which, in conventional VH domains are involved in interdomain interactions, and the presence of a long third complementarity-determining region (CDR3) which is frequently constrained by an interloop disulphide bond. Here, we describe a large (152) set of Lama glama VHH cDNAs. Based on amino acid sequence similarity, these and other published Camelid VHHs were classified into four subfamilies. Three subfamilies are absent in dromedaries, which have been the primary source of VHHs thus far. Comparison of these subfamilies to conventional VH regions reveals new features characteristic of VHHs and shows that many features earlier regarded as characteristic of VHHs in general are actually subfamily specific. A long CDR3 with a concomitant putative additional disulphide bond is only observed in two VHH subfamilies. Furthermore, we identified new VHH-characteristic residues at positions forming interdomain sites in conventional VH domains. The VHH subfamilies also differ from each other and conventional VH domains in the canonical structure of CDR1 and CDR2, mean CDR3 length, and amino acid residue variability. Since different VHH-characteristic residues are observed in all four subfamilies, these subfamilies must have evolved independently from classical VH domains.
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llama heavy chain v regions consist of at least four distinct subfamilies revealing novel sequence features
Molecular Immunology, 2000Co-Authors: M M Harmsen, Leon G J Frenken, Robin C Ruuls, Isaac J Nijman, Theodoor Niewold, Bernard De GeusAbstract:In addition to conventional antibodies (Abs), Camelids possess Abs consisting of only heavy chains. The variable domain of such a heavy-chain Ab (VHH) is fully capable of antigen (Ag) binding. Earlier analysis of 47 VHHs showed sequence features unique to VHH domains. These include the presence of characteristic amino acid substitutions in positions which, in conventional VH domains are involved in interdomain interactions, and the presence of a long third complementarity-determining region (CDR3) which is frequently constrained by an interloop disulphide bond. Here, we describe a large (152) set of Lama glama VHH cDNAs. Based on amino acid sequence similarity, these and other published Camelid VHHs were classified into four subfamilies. Three subfamilies are absent in dromedaries, which have been the primary source of VHHs thus far. Comparison of these subfamilies to conventional VH regions reveals new features characteristic of VHHs and shows that many features earlier regarded as characteristic of VHHs in general are actually subfamily specific. A long CDR3 with a concomitant putative additional disulphide bond is only observed in two VHH subfamilies. Furthermore, we identified new VHH-characteristic residues at positions forming interdomain sites in conventional VH domains. The VHH subfamilies also differ from each other and conventional VH domains in the canonical structure of CDR1 and CDR2, mean CDR3 length, and amino acid residue variability. Since different VHH-characteristic residues are observed in all four subfamilies, these subfamilies must have evolved independently from classical VH domains.
Terje Raudsepp - One of the best experts on this subject based on the ideXlab platform.
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Image_1_Comparative FISH-Mapping of MC1R, ASIP, and TYRP1 in New and Old World Camelids and Association Analysis With Coat Color Phenotypes in the Dromedary (Camelus dromedarius).TIF
2019Co-Authors: Fahad Alshanbari, Caitlin Castaneda, Rytis Juras, Andrew Hillhouse, Mayra N. Mendoza, Gustavo A. Gutiérrez, Federico Abel Ponce De León, Terje RaudseppAbstract:Melanocortin 1 receptor (MC1R), the agouti signaling protein (ASIP), and tyrosinase related protein 1 (TYRP1) are among the major regulators of pigmentation in mammals. Recently, MC1R and ASIP sequence variants were associated with white and black/dark brown coat colors, respectively, in the dromedary. Here we confirmed this association by independent sequencing and mutation discovery of MC1R and ASIP coding regions and by TaqMan genotyping in 188 dromedaries from Saudi Arabia and United States, including 38 black, 53 white, and 97 beige/brown/red animals. We showed that heterozygosity for a missense mutation c.901C > T in MC1R is sufficient for the white coat color suggesting a possible dominant negative effect. Likewise, we confirmed that the majority of black dromedaries were homozygous for a frameshift mutation in ASIP exon 2, except for 4 animals, which were heterozygous. In search for additional mutations underlying the black color, we identified another frameshift mutation in ASIP exon 4 and 6 new variants in MC1R including a significantly associated SNP in 3′UTR. In pursuit of sequence variants that may modify dromedary wild-type color from dark-reddish brown to light beige, we identified 4 SNPs and one insertion in TYRP1 non-coding regions. However, none of these were associated with variations in wild-type colors. Finally, the three genes were cytogenetically mapped in New World (alpaca) and Old World (dromedary and Bactrian camel) Camelids. The MC1R was assigned to chr21, ASIP to chr19 and TYRP1 to chr4 in all 3 species confirming extensive conservation of Camelid karyotypes. Notably, while the locations of ASIP and TYRP1 were in agreement with human-Camelid comparative map, mapping MC1R identified a new evolutionary conserved synteny segment between Camelid chromosome 21 and HSA16. The findings contribute to coat color genomics and the development of molecular tests in Camelids and toward the chromosome level reference assemblies of Camelid genomes.
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Table_2_Comparative FISH-Mapping of MC1R, ASIP, and TYRP1 in New and Old World Camelids and Association Analysis With Coat Color Phenotypes in the Dromedary (Camelus dromedarius).XLSX
2019Co-Authors: Fahad Alshanbari, Caitlin Castaneda, Rytis Juras, Andrew Hillhouse, Mayra N. Mendoza, Gustavo A. Gutiérrez, Federico Abel Ponce De León, Terje RaudseppAbstract:Melanocortin 1 receptor (MC1R), the agouti signaling protein (ASIP), and tyrosinase related protein 1 (TYRP1) are among the major regulators of pigmentation in mammals. Recently, MC1R and ASIP sequence variants were associated with white and black/dark brown coat colors, respectively, in the dromedary. Here we confirmed this association by independent sequencing and mutation discovery of MC1R and ASIP coding regions and by TaqMan genotyping in 188 dromedaries from Saudi Arabia and United States, including 38 black, 53 white, and 97 beige/brown/red animals. We showed that heterozygosity for a missense mutation c.901C > T in MC1R is sufficient for the white coat color suggesting a possible dominant negative effect. Likewise, we confirmed that the majority of black dromedaries were homozygous for a frameshift mutation in ASIP exon 2, except for 4 animals, which were heterozygous. In search for additional mutations underlying the black color, we identified another frameshift mutation in ASIP exon 4 and 6 new variants in MC1R including a significantly associated SNP in 3′UTR. In pursuit of sequence variants that may modify dromedary wild-type color from dark-reddish brown to light beige, we identified 4 SNPs and one insertion in TYRP1 non-coding regions. However, none of these were associated with variations in wild-type colors. Finally, the three genes were cytogenetically mapped in New World (alpaca) and Old World (dromedary and Bactrian camel) Camelids. The MC1R was assigned to chr21, ASIP to chr19 and TYRP1 to chr4 in all 3 species confirming extensive conservation of Camelid karyotypes. Notably, while the locations of ASIP and TYRP1 were in agreement with human-Camelid comparative map, mapping MC1R identified a new evolutionary conserved synteny segment between Camelid chromosome 21 and HSA16. The findings contribute to coat color genomics and the development of molecular tests in Camelids and toward the chromosome level reference assemblies of Camelid genomes.
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Data_Sheet_1_Comparative FISH-Mapping of MC1R, ASIP, and TYRP1 in New and Old World Camelids and Association Analysis With Coat Color Phenotypes in the Dromedary (Camelus dromedarius).PDF
2019Co-Authors: Fahad Alshanbari, Caitlin Castaneda, Rytis Juras, Andrew Hillhouse, Mayra N. Mendoza, Gustavo A. Gutiérrez, Federico Abel Ponce De León, Terje RaudseppAbstract:Melanocortin 1 receptor (MC1R), the agouti signaling protein (ASIP), and tyrosinase related protein 1 (TYRP1) are among the major regulators of pigmentation in mammals. Recently, MC1R and ASIP sequence variants were associated with white and black/dark brown coat colors, respectively, in the dromedary. Here we confirmed this association by independent sequencing and mutation discovery of MC1R and ASIP coding regions and by TaqMan genotyping in 188 dromedaries from Saudi Arabia and United States, including 38 black, 53 white, and 97 beige/brown/red animals. We showed that heterozygosity for a missense mutation c.901C > T in MC1R is sufficient for the white coat color suggesting a possible dominant negative effect. Likewise, we confirmed that the majority of black dromedaries were homozygous for a frameshift mutation in ASIP exon 2, except for 4 animals, which were heterozygous. In search for additional mutations underlying the black color, we identified another frameshift mutation in ASIP exon 4 and 6 new variants in MC1R including a significantly associated SNP in 3′UTR. In pursuit of sequence variants that may modify dromedary wild-type color from dark-reddish brown to light beige, we identified 4 SNPs and one insertion in TYRP1 non-coding regions. However, none of these were associated with variations in wild-type colors. Finally, the three genes were cytogenetically mapped in New World (alpaca) and Old World (dromedary and Bactrian camel) Camelids. The MC1R was assigned to chr21, ASIP to chr19 and TYRP1 to chr4 in all 3 species confirming extensive conservation of Camelid karyotypes. Notably, while the locations of ASIP and TYRP1 were in agreement with human-Camelid comparative map, mapping MC1R identified a new evolutionary conserved synteny segment between Camelid chromosome 21 and HSA16. The findings contribute to coat color genomics and the development of molecular tests in Camelids and toward the chromosome level reference assemblies of Camelid genomes.
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Comparative FISH-Mapping of MC1R, ASIP, and TYRP1 in New and Old World Camelids and Association Analysis With Coat Color Phenotypes in the Dromedary (Camelus dromedarius)
Frontiers Media S.A., 2019Co-Authors: Fahad Alshanbari, Caitlin Castaneda, Rytis Juras, Andrew Hillhouse, Mayra N. Mendoza, Gustavo A. Gutiérrez, Federico Abel Ponce De León, Terje RaudseppAbstract:Melanocortin 1 receptor (MC1R), the agouti signaling protein (ASIP), and tyrosinase related protein 1 (TYRP1) are among the major regulators of pigmentation in mammals. Recently, MC1R and ASIP sequence variants were associated with white and black/dark brown coat colors, respectively, in the dromedary. Here we confirmed this association by independent sequencing and mutation discovery of MC1R and ASIP coding regions and by TaqMan genotyping in 188 dromedaries from Saudi Arabia and United States, including 38 black, 53 white, and 97 beige/brown/red animals. We showed that heterozygosity for a missense mutation c.901C > T in MC1R is sufficient for the white coat color suggesting a possible dominant negative effect. Likewise, we confirmed that the majority of black dromedaries were homozygous for a frameshift mutation in ASIP exon 2, except for 4 animals, which were heterozygous. In search for additional mutations underlying the black color, we identified another frameshift mutation in ASIP exon 4 and 6 new variants in MC1R including a significantly associated SNP in 3′UTR. In pursuit of sequence variants that may modify dromedary wild-type color from dark-reddish brown to light beige, we identified 4 SNPs and one insertion in TYRP1 non-coding regions. However, none of these were associated with variations in wild-type colors. Finally, the three genes were cytogenetically mapped in New World (alpaca) and Old World (dromedary and Bactrian camel) Camelids. The MC1R was assigned to chr21, ASIP to chr19 and TYRP1 to chr4 in all 3 species confirming extensive conservation of Camelid karyotypes. Notably, while the locations of ASIP and TYRP1 were in agreement with human-Camelid comparative map, mapping MC1R identified a new evolutionary conserved synteny segment between Camelid chromosome 21 and HSA16. The findings contribute to coat color genomics and the development of molecular tests in Camelids and toward the chromosome level reference assemblies of Camelid genomes
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construction of two whole genome radiation hybrid panels for dromedary camelus dromedarius 5000rad and 15000rad
Scientific Reports, 2018Co-Authors: Polina L Perelman, Pamela A Burger, Rudolf Pichler, Anna Gaggl, Denis M Larkin, Terje Raudsepp, Fahad Alshanbari, Heather M Holl, Samantha A Brooks, Kathiravan PeriasamyAbstract:The availability of genomic resources including linkage information for Camelids has been very limited. Here, we describe the construction of a set of two radiation hybrid (RH) panels (5000RAD and 15000RAD) for the dromedary (Camelus dromedarius) as a permanent genetic resource for camel genome researchers worldwide. For the 5000RAD panel, a total of 245 female camel-hamster radiation hybrid clones were collected, of which 186 were screened with 44 custom designed marker loci distributed throughout camel genome. The overall mean retention frequency (RF) of the final set of 93 hybrids was 47.7%. For the 15000RAD panel, 238 male dromedary-hamster radiation hybrid clones were collected, of which 93 were tested using 44 PCR markers. The final set of 90 clones had a mean RF of 39.9%. This 15000RAD panel is an important high-resolution complement to the main 5000RAD panel and an indispensable tool for resolving complex genomic regions. This valuable genetic resource of dromedary RH panels is expected to be instrumental for constructing a high resolution camel genome map. Construction of the set of RH panels is essential step toward chromosome level reference quality genome assembly that is critical for advancing Camelid genomics and the development of custom genomic tools.
Fred J Longstaffe - One of the best experts on this subject based on the ideXlab platform.
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early horizon Camelid management practices in the nepena valley north central coast of peru
Environmental Archaeology, 2016Co-Authors: Paul Szpak, David Chicoine, Jeanfrancois Millaire, Christine D White, Rebecca Parry, Fred J LongstaffeAbstract:South American Camelids (llamas and alpacas) were of great economic, social and ritual significance in the pre-Hispanic Andes. Although these animals are largely limited to high-altitude (>3500 masl) pastures, it has been hypothesised that Camelids were also raised at lower altitudes in the arid coastal river valleys. Previous isotopic studies of Early Intermediate Period (c. 200 BC–AD 600) and Middle Horizon (c. AD 600–1100) Camelids support this argument. Here, we utilise carbon and nitrogen isotopic analyses of Camelid bone collagen from the Early Horizon (c. 800–200 BC) sites of Caylan and Huambacho on the north-central coast of Peru to examine the management of these animals during the first millennium BC. Most of the Camelid isotopic compositions are consistent with the acquisition of animals that were part of caravans, moving between the coast and the highlands. A small number of the animals may have been raised on the coast, suggesting that the practice of coastal Camelid husbandry was in the expe...
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small scale Camelid husbandry on the north coast of peru viru valley insight from stable isotope analysis
Journal of Anthropological Archaeology, 2014Co-Authors: Paul Szpak, Jeanfrancois Millaire, Christine D White, Fred J LongstaffeAbstract:This study presents carbon and nitrogen isotopic compositions for bone collagen and serially sampled hair from a large collection of South American Camelids from two Early Intermediate Period (c. 200 BC to AD 800) sites (Huaca Gallinazo and Huaca Santa Clara) in the Viru Valley (north coast of Peru). The isotopic compositions of these Camelids are consistent with plant isotopic compositions from coastal and low altitude settings, but not from high altitude environments, suggesting that at least some of these animals were raised locally. We present several methodological approaches with respect to the treatment of isotopic data from archaeological contexts, outlining quantitative approaches that can provide considerable insight into isotopic variation (within groups, within individuals, between groups, between individuals), as well as temporal variation in isotopic compositions in incrementally growing tissues. We contend that focusing explicitly on variation in animal life histories has the greatest potential with respect to better understanding human–animal interactions in the past. The results demonstrate a large amount of isotopic variability among individuals and an inconsistent amount of within-individual variation, with no consistent shift in the diet leading up to the time of death for a group of animals from a single ritual event. This result suggests that Camelid husbandry in the Viru Valley was a small-scale activity, with groups of Camelids being managed by families or other small social units. Animals were likely kept primarily in close association to human habitation sites and provided with a diverse array of fodder. These prolonged interactions, occurring at a limited spatial scale, would have allowed a high degree of mutual familiarity to develop between humans and animals. Isotopic compositions for late Middle Horizon (c. AD 1100) sacrificed llamas from Huaca Santa Clara are consistent with Early Intermediate Period Camelids, suggesting temporal stability in this small-scale Camelid management strategy on the coast, which was fundamentally different from Camelid herding in the pastures of the Andean highlands. Isotopic analysis of prehistoric livestock has great potential with respect to better understanding animal husbandry practices and human–animal interactions in the broadest sense because the data provide insight into the ways in which animals lived, rather than the manner in which they died. The variation-centered methodologies outlined in this paper provide a framework with which to approach some of these issues, highlighting the significance of understanding variability in livestock life histories.
M M Harmsen - One of the best experts on this subject based on the ideXlab platform.
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llama heavy chain v regions consist of at least four distinct subfamilies revealing novel sequence features
Molecular Immunology, 2000Co-Authors: M M Harmsen, Leon G J Frenken, Robin C Ruuls, Isaac J Nijman, Theodoor Niewold, Bernard De GeusAbstract:In addition to conventional antibodies (Abs), Camelids possess Abs consisting of only heavy chains. The variable domain of such a heavy-chain Ab (VHH) is fully capable of antigen (Ag) binding. Earlier analysis of 47 VHHs showed sequence features unique to VHH domains. These include the presence of characteristic amino acid substitutions in positions which, in conventional VH domains are involved in interdomain interactions, and the presence of a long third complementarity-determining region (CDR3) which is frequently constrained by an interloop disulphide bond. Here, we describe a large (152) set of Lama glama VHH cDNAs. Based on amino acid sequence similarity, these and other published Camelid VHHs were classified into four subfamilies. Three subfamilies are absent in dromedaries, which have been the primary source of VHHs thus far. Comparison of these subfamilies to conventional VH regions reveals new features characteristic of VHHs and shows that many features earlier regarded as characteristic of VHHs in general are actually subfamily specific. A long CDR3 with a concomitant putative additional disulphide bond is only observed in two VHH subfamilies. Furthermore, we identified new VHH-characteristic residues at positions forming interdomain sites in conventional VH domains. The VHH subfamilies also differ from each other and conventional VH domains in the canonical structure of CDR1 and CDR2, mean CDR3 length, and amino acid residue variability. Since different VHH-characteristic residues are observed in all four subfamilies, these subfamilies must have evolved independently from classical VH domains.
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llama heavy chain v regions consist of at least four distinct subfamilies revealing novel sequence features
Molecular Immunology, 2000Co-Authors: M M Harmsen, Leon G J Frenken, Robin C Ruuls, Isaac J Nijman, Theodoor Niewold, Bernard De GeusAbstract:In addition to conventional antibodies (Abs), Camelids possess Abs consisting of only heavy chains. The variable domain of such a heavy-chain Ab (VHH) is fully capable of antigen (Ag) binding. Earlier analysis of 47 VHHs showed sequence features unique to VHH domains. These include the presence of characteristic amino acid substitutions in positions which, in conventional VH domains are involved in interdomain interactions, and the presence of a long third complementarity-determining region (CDR3) which is frequently constrained by an interloop disulphide bond. Here, we describe a large (152) set of Lama glama VHH cDNAs. Based on amino acid sequence similarity, these and other published Camelid VHHs were classified into four subfamilies. Three subfamilies are absent in dromedaries, which have been the primary source of VHHs thus far. Comparison of these subfamilies to conventional VH regions reveals new features characteristic of VHHs and shows that many features earlier regarded as characteristic of VHHs in general are actually subfamily specific. A long CDR3 with a concomitant putative additional disulphide bond is only observed in two VHH subfamilies. Furthermore, we identified new VHH-characteristic residues at positions forming interdomain sites in conventional VH domains. The VHH subfamilies also differ from each other and conventional VH domains in the canonical structure of CDR1 and CDR2, mean CDR3 length, and amino acid residue variability. Since different VHH-characteristic residues are observed in all four subfamilies, these subfamilies must have evolved independently from classical VH domains.
Leon G J Frenken - One of the best experts on this subject based on the ideXlab platform.
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llama heavy chain v regions consist of at least four distinct subfamilies revealing novel sequence features
Molecular Immunology, 2000Co-Authors: M M Harmsen, Leon G J Frenken, Robin C Ruuls, Isaac J Nijman, Theodoor Niewold, Bernard De GeusAbstract:In addition to conventional antibodies (Abs), Camelids possess Abs consisting of only heavy chains. The variable domain of such a heavy-chain Ab (VHH) is fully capable of antigen (Ag) binding. Earlier analysis of 47 VHHs showed sequence features unique to VHH domains. These include the presence of characteristic amino acid substitutions in positions which, in conventional VH domains are involved in interdomain interactions, and the presence of a long third complementarity-determining region (CDR3) which is frequently constrained by an interloop disulphide bond. Here, we describe a large (152) set of Lama glama VHH cDNAs. Based on amino acid sequence similarity, these and other published Camelid VHHs were classified into four subfamilies. Three subfamilies are absent in dromedaries, which have been the primary source of VHHs thus far. Comparison of these subfamilies to conventional VH regions reveals new features characteristic of VHHs and shows that many features earlier regarded as characteristic of VHHs in general are actually subfamily specific. A long CDR3 with a concomitant putative additional disulphide bond is only observed in two VHH subfamilies. Furthermore, we identified new VHH-characteristic residues at positions forming interdomain sites in conventional VH domains. The VHH subfamilies also differ from each other and conventional VH domains in the canonical structure of CDR1 and CDR2, mean CDR3 length, and amino acid residue variability. Since different VHH-characteristic residues are observed in all four subfamilies, these subfamilies must have evolved independently from classical VH domains.
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llama heavy chain v regions consist of at least four distinct subfamilies revealing novel sequence features
Molecular Immunology, 2000Co-Authors: M M Harmsen, Leon G J Frenken, Robin C Ruuls, Isaac J Nijman, Theodoor Niewold, Bernard De GeusAbstract:In addition to conventional antibodies (Abs), Camelids possess Abs consisting of only heavy chains. The variable domain of such a heavy-chain Ab (VHH) is fully capable of antigen (Ag) binding. Earlier analysis of 47 VHHs showed sequence features unique to VHH domains. These include the presence of characteristic amino acid substitutions in positions which, in conventional VH domains are involved in interdomain interactions, and the presence of a long third complementarity-determining region (CDR3) which is frequently constrained by an interloop disulphide bond. Here, we describe a large (152) set of Lama glama VHH cDNAs. Based on amino acid sequence similarity, these and other published Camelid VHHs were classified into four subfamilies. Three subfamilies are absent in dromedaries, which have been the primary source of VHHs thus far. Comparison of these subfamilies to conventional VH regions reveals new features characteristic of VHHs and shows that many features earlier regarded as characteristic of VHHs in general are actually subfamily specific. A long CDR3 with a concomitant putative additional disulphide bond is only observed in two VHH subfamilies. Furthermore, we identified new VHH-characteristic residues at positions forming interdomain sites in conventional VH domains. The VHH subfamilies also differ from each other and conventional VH domains in the canonical structure of CDR1 and CDR2, mean CDR3 length, and amino acid residue variability. Since different VHH-characteristic residues are observed in all four subfamilies, these subfamilies must have evolved independently from classical VH domains.
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Camelid heavy chain variable domains provide efficient combining sites to haptens
Biochemistry, 2000Co-Authors: Silvia Spinelli, Leon G J Frenken, Pim Hermans, Theo Verrips, Kieron Brown, Mariella Tegoni, Christian CambillauAbstract:Camelids can produce antibodies devoid of light chains and CH1 domains (Hamers-Casterman, C. et al. (1993) Nature 363, 446-448). Camelid heavy-chain variable domains (VHH) have high affinities for protein antigens and the structures of two of these complexes have been determined (Desmyter, A. et al. (1996) Nature Struc. Biol. 3, 803-811; Decanniere, K. et al. (1999) Structure 7, 361-370). However, the small size of these VHHs and their monomeric nature bring into question their capacity to bind haptens. Here, we have successfully raised llama antibodies against the hapten azo-dye Reactive Red (RR6) and determined the crystal structure of the complex between a dimer of this hapten and a VHH fragment. The surface of interaction between the VHH and the dimeric hapten is large, with an area of ca. 300 A(2); this correlates well with the low-dissociation constant of 22 nM measured for the monomer. The VHH fragment provides an efficient combining site to the RR6, using its three CDR loops. In particular, CDR1 provides a strong interaction to the hapten through two histidine residues bound to its copper atoms. VHH fragments might, therefore, prove to be valuable tools for selecting, removing, or capturing haptens. They are likely to play a role in biotechnology extending beyond protein recognition alone.
