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Manuel A Patarroyo - One of the best experts on this subject based on the ideXlab platform.

  • the molecular basis for peptide based antimalarial vaccine development targeting erythrocyte invasion by p falciparum
    Biochemical and Biophysical Research Communications, 2021
    Co-Authors: Jorge Azaconde, Cesar Reyes, Carlos F Suarez, Manuel A Patarroyo
    Abstract:

    Abstract This work describes a methodology for developing a minimal, subunit-based, multi-epitope, multi-stage, chemically-synthesised, anti-Plasmodium falciparum malaria vaccine. Some modified high activity binding peptides (mHABPs) derived from functionally relevant P. falciparum MSP, RH5 and AMA-1 conserved amino acid regions (cHABPs) for parasite binding to and invasion of red blood cells (RBC) were selected. They were highly immunogenic as assessed by indirect immunofluorescence (IFA) and Western blot (WB) assays and protective immune response-inducers against malarial challenge in the Aotus monkey experimental model. NetMHCIIpan 4.0 was used for predicting peptide-Aotus/human major histocompatibility class II (MHCII) binding affinity in silico due to the similarity between Aotus and human immune system molecules; ∼50% of Aotus MHCII allele molecules have a counterpart in the human immune system, being Aotus-specific, whilst others enabled recognition of their human counterparts. Some peptides’ 1H-NMR-assessed structural conformation was determined to explain residue modifications in mHABPs inducing secondary structure changes. These directly influenced immunological behaviour, thereby highlighting the relationship with MHCII antigen presentation. The data obtained in such functional, immunological, structural and predictive approach suggested that some of these peptides could be excellent components of a fully-protective antimalarial vaccine.

  • identification and diversity of killer cell ig like receptors in Aotus vociferans a new world monkey
    PLOS ONE, 2013
    Co-Authors: Diego Garzonospina, Manuel E. Patarroyo, Luis F. Cadavid, Carolina Lopez, Manuel A Patarroyo
    Abstract:

    Previous BAC clone analysis of the Platyrrhini owl monkey KIRs have shown an unusual genetic structure in some loci. Therefore, cDNAs encoding KIR molecules from eleven Aotus vociferans monkeys were characterized here; ten putative KIR loci were found, some of which encoded atypical proteins such as KIR4DL and transcripts predicted to encode a D0+D1 configuration (AOTVOKIR2DL1*01v1) which appear to be unique in the Aotus genus. Furthermore, alternative splicing was found as a likely mechanism for producing activator receptors in A. vociferans species. KIR proteins from New World monkeys may be split into three new lineages according to domain by domain phylogenetic analysis. Although the A. vociferans KIR family displayed a high divergence among paralogous genes, individual loci were limited in their genetic polymorphism. Selection analysis showed that both constrained and rapid evolution may operate within the AvKIR family. The frequent alternative splicing (as a likely mechanism generating activator receptors), the presence of KIR4DL and KIR2DL1 (D0+D1) molecules and other data reported here suggest that the KIR family in Aotus has had a rapid evolution, independent from its Catarrhini counterparts.

  • Quantifying Aotus monkey cytokines by real-time quantitative RT-PCR.
    Cytokine, 2004
    Co-Authors: Yago Pico De Coaña, Manuel E. Patarroyo, Isabela Cajiao, Catalina Mosquera, Carlos A. Barrero, Manuel A Patarroyo
    Abstract:

    Abstract Aotus spp. monkeys are considered the ideal model for studying the progress of malarial infection and the immune response it elicits. We describe the use of a recently developed technique, real-time quantitative RT-PCR, to quantify several Aotus monkey cytokine mRNAs involved in Th1/Th2 responses (IL-4, IL-10, TNF-β and IFN-γ). Specific primers were designed for each cytokine and standard curves were constructed using serial dilutions of pDNA containing each target sequence. Results were normalized to GAPDH housekeeping gene expression levels. Standard curves showed high correlation coefficients and were linear over a wide range of copy numbers. Quantification of Aotus samples showed little intra- and inter-experiment variation, thus, the technique has proven to be highly reproducible and sensitive allowing us to detect as little as 25 copies/μl of target DNA. This technique will allow studying Th1 and Th2 cytokine patterns elicited in response to infection for prospectively evaluating the efficacy of malarial vaccines.

  • Sequence and diversity of T-cell receptor alpha V , J , and C genes of the owl monkey Aotus nancymaae
    Immunogenetics, 1999
    Co-Authors: William Vecino, Raul Rodriguez, Manuel A Patarroyo, Claudia Daubenberger, Alberto Moreno, Gerd Pluschke
    Abstract:

    We cloned and sequenced TcR alpha chain cDNA of three healthy Aotus nancymaae monkeys. Fifteen different TRAJ segments and 9 different TRAV genes were identified in the 29 rearrangements analyzed. As expected from the greater phylogenetic distance, A. nancymaae TRA gene sequences diverged more from the human sequences than those of the chimpanzee or the rhesus macaque. However, no Aotus TRAJ segment or TRAV gene was found which lacked a human counterpart. These counterparts were AJ02, AJ05, AJ09, AJ15, AJ22, AJ23, AJ28, AJ30, AJ32, AJ34, AJ37, AJ40, AJ42, AJ45, AJ52 and AV2S1, AV2S3, AV3S1, AV8S1, AV12S1, AV15S1, ADV21S1/DV5, AV22S1S and AV23S1, respectively. In most cases the identity of amino acid sequences between corresponding Aotus and human genes was greater than 80%. This marked conservation of TRA gene sequences indicates a close structural relationship of Aotus and human TcR and demonstrates that the TcR repertoire in primates is remarkably stable. The results support the concept of using Aotus monkeys, which are susceptible to infection with the human malaria parasite Plasmodium falciparum, as an animal model for the evaluation of molecularly defined malaria vaccine candidates.

Manuel E. Patarroyo - One of the best experts on this subject based on the ideXlab platform.

  • identification and diversity of killer cell ig like receptors in Aotus vociferans a new world monkey
    PLOS ONE, 2013
    Co-Authors: Diego Garzonospina, Manuel E. Patarroyo, Luis F. Cadavid, Carolina Lopez, Manuel A Patarroyo
    Abstract:

    Previous BAC clone analysis of the Platyrrhini owl monkey KIRs have shown an unusual genetic structure in some loci. Therefore, cDNAs encoding KIR molecules from eleven Aotus vociferans monkeys were characterized here; ten putative KIR loci were found, some of which encoded atypical proteins such as KIR4DL and transcripts predicted to encode a D0+D1 configuration (AOTVOKIR2DL1*01v1) which appear to be unique in the Aotus genus. Furthermore, alternative splicing was found as a likely mechanism for producing activator receptors in A. vociferans species. KIR proteins from New World monkeys may be split into three new lineages according to domain by domain phylogenetic analysis. Although the A. vociferans KIR family displayed a high divergence among paralogous genes, individual loci were limited in their genetic polymorphism. Selection analysis showed that both constrained and rapid evolution may operate within the AvKIR family. The frequent alternative splicing (as a likely mechanism generating activator receptors), the presence of KIR4DL and KIR2DL1 (D0+D1) molecules and other data reported here suggest that the KIR family in Aotus has had a rapid evolution, independent from its Catarrhini counterparts.

  • Owl monkey MHC-DRB exon 2 reveals high similarity with several HLA-DRB lineages
    Immunogenetics, 2006
    Co-Authors: Carlos F Suarez, Juan E. Baquero, Esperanza Trujillo, Manuel E. Patarroyo, Mónica Estupiñán, Carlos Parra, Raul Rodriguez
    Abstract:

    One hundred and ten novel MHC-DRB gene exon 2 nucleotide sequences were sequenced in 96 monkeys from three owl monkey species (67 from Aotus nancymaae , 30 from Aotus nigriceps and 13 from Aotus vociferans ). Owl monkeys, like humans, have high MHC-DRB allele polymorphism, revealing a striking similarity with several human allele lineages in the peptide binding region and presenting major convergence with DRB lineages from several Catarrhini (humans, apes and Old World monkeys) rather than with others New World monkeys (Platyrrhini). The parallelism between human and Aotus MHC-DRB reveals additional similarities regarding variability pattern, selection pressure and physicochemical constraints in amino acid replacements. These observations concerning previous findings of similarity between the Aotus immune system molecules and their human counterparts affirm this specie’s usefulness as an excellent animal model in biomedical research.

  • Quantifying Aotus monkey cytokines by real-time quantitative RT-PCR.
    Cytokine, 2004
    Co-Authors: Yago Pico De Coaña, Manuel E. Patarroyo, Isabela Cajiao, Catalina Mosquera, Carlos A. Barrero, Manuel A Patarroyo
    Abstract:

    Abstract Aotus spp. monkeys are considered the ideal model for studying the progress of malarial infection and the immune response it elicits. We describe the use of a recently developed technique, real-time quantitative RT-PCR, to quantify several Aotus monkey cytokine mRNAs involved in Th1/Th2 responses (IL-4, IL-10, TNF-β and IFN-γ). Specific primers were designed for each cytokine and standard curves were constructed using serial dilutions of pDNA containing each target sequence. Results were normalized to GAPDH housekeeping gene expression levels. Standard curves showed high correlation coefficients and were linear over a wide range of copy numbers. Quantification of Aotus samples showed little intra- and inter-experiment variation, thus, the technique has proven to be highly reproducible and sensitive allowing us to detect as little as 25 copies/μl of target DNA. This technique will allow studying Th1 and Th2 cytokine patterns elicited in response to infection for prospectively evaluating the efficacy of malarial vaccines.

  • Partial characterization of the CD45 phosphatase cDNA in the owl monkey (Aotus vociferans).
    American journal of primatology, 2002
    Co-Authors: Gladis E. Montoya, Jean Paul Vernot, Manuel E. Patarroyo
    Abstract:

    CD45 is a protein tyrosine phosphatase implicated in T and B cell activation, differentiation, and development. It dephosphorylates specific tyrosine residues on its substrates, principally on the Src-family of protein tyrosine kinases, thus regulating T cell or B cell activation during the immune response. In this study, we present the partial CD45 nucleotide and deduced amino-acid sequences for the owl monkey (Aotus vociferens). There is 97% identity in the nucleotide sequence and 96% in the amino acid sequence with the human counterpart. Aotus CD45 undergoes alternative splicing on the extracelular N-terminal tail, and has several conserved features characteristic of other species. This includes the two Tyr phosphatase domains and some residues and/or motifs involved in docking of signaling molecules, intramolecular interactions, and CD45 activity and activity regulation (YINAS, GXGXXG, WPD, and YWP motifs, and the Cys residues). This suggests that the Aotus CD45 molecule is a functional enzyme and that initial lymphocyte activation in Aotus monkeys and humans is very similar. Together with previous reports from our laboratory, this work supports the contention that immune responses in Aotus are similar to those of humans, and supports the strategy for using this experimental model for studies on activation of T lymphocytes in response to specific antigens.

  • Sequence and diversity of DRB genes of Aotus nancymaae, a primate model for human malaria parasites.
    Immunogenetics, 2000
    Co-Authors: J. Javier Nino-vasquez, Raul Rodriguez, Alberto Moreno, Gerd Pluschke, Manuel E. Patarroyo, Denise Vogel, Claudia Daubenberger
    Abstract:

    The New World primate Aotus nancymaae is susceptible to infection with the human malaria parasite Plasmodium falciparum and Plasmodium vivax and has therefore been recommended by the World Health Organization as a model for evaluation of malaria vaccine candidates. We present here a first step in the molecular characterization of the major histocompatibility complex (MHC) class II DRB genes of Aotus nancymaae (owl monkey or night monkey) by nucleotide sequence analysis of the polymorphic exon 2 segments. In a group of 15 nonrelated animals captivated in the wild, 34 MHC DRB alleles could be identified. Six allelic lineages were detected, two of them having human counterparts, while two other lineages have not been described in any other New World monkey species studied. As in the common marmoset, the diversity of DRB alleles appears to have arisen largely by point mutations in the β-pleated sheets and by frequent exchange of fixed sequence motifs in the α-helical portion. Pairs of alleles differing only at amino acid position b86 by an exchange of valine to glycine are present in Aotus, as in humans. Essential amino acid residues contributing to MHC DR peptide binding pockets number 1 and 4 are conserved or semiconserved between HLA-DR and Aona-DRB molecules, indicating a capacity to bind similar peptide repertoires. These results support fully our using Aotus monkeys as an animal model for evaluation of future subunit vaccine candidates.

Manuel Elkin Patarroyo - One of the best experts on this subject based on the ideXlab platform.

  • Reference strand conformational analysis (RSCA) is a valuable tool in identifying MHC-DRB sequences in three species of Aotus monkeys
    Immunogenetics, 2006
    Co-Authors: Juan E. Baquero, Manuel Elkin Patarroyo, Carlos F Suarez, Santiago Miranda, Oscar Murillo, Heidy Eliana Mateus, Esperanza Trujillo, Carlos Parra-lopez
    Abstract:

    The Aotus monkey has been of great value in the pre-clinical study of malaria vaccine candidates. Several components of this primate's immune system have been studied and they display great similarity to their human counterparts. Cloning and sequencing studies have revealed extensive sequence polymorphisms in Aotus MHC-DRB with very high similarities to several human allelic lineages, grouping at least nine distinct MHC-DRB lineages. As the efficacy of peptide vaccines in this animal model may be strongly influenced by exon 2 MHC-DRB polymorphism, the availability of a reliable and rapid MHC-DRB typing method for three species of Aotus (Aotus nancymaae, Aotus vociferans and Aotus nigriceps) is necessary. Reference strand conformational analysis (RSCA) was used here for differentiating the distinctive Aotus MHC-DRB sequences' mobility using five fluorescently labelled references proved to be very useful for resolving closely related sequences, establishing the number of sequences transcribed in a particular monkey and their identity. The RSCA method's reliability in terms of identifying Aotus MHC-DRB sequences will facilitate evaluating individual responsiveness to vaccines and prompt studies associating susceptibility/resistance to infectious agents or auto-immune disease, for which Aotus monkeys may be considered to be an appropriate animal model.

  • Quantifying Aotus monkey cytokines by real-time quantitative RT-PCR.
    Cytokine, 2004
    Co-Authors: Yago Pico De Coaña, Manuel Elkin Patarroyo, Carlos Barrero, Isabela Cajiao, Catalina Mosquera, Manuel Alfonso Patarroyo
    Abstract:

    Aotus spp. monkeys are considered the ideal model for studying the progress of malarial infection and the immune response it elicits. We describe the use of a recently developed technique, real-time quantitative RT-PCR, to quantify several Aotus monkey cytokine mRNAs involved in Th1/Th2 responses (IL-4, IL-10, TNF-beta and IFN-gamma). Specific primers were designed for each cytokine and standard curves were constructed using serial dilutions of pDNA containing each target sequence. Results were normalized to GAPDH housekeeping gene expression levels. Standard curves showed high correlation coefficients and were linear over a wide range of copy numbers. Quantification of Aotus samples showed little intra- and inter-experiment variation, thus, the technique has proven to be highly reproducible and sensitive allowing us to detect as little as 25 copies/microl of target DNA. This technique will allow studying Th1 and Th2 cytokine patterns elicited in response to infection for prospectively evaluating the efficacy of malarial vaccines.

  • Proliferative response of peripheral blood lymphocytes to mitogens in the owl monkey Aotus nancymae.
    Journal of Medical Primatology, 2003
    Co-Authors: Alberto Pinzón-charry, Jean Paul Vernot, Raul Rodriguez, Manuel Elkin Patarroyo
    Abstract:

    : The new world primate Aotus sp. has been recommended by the World Health Organization as a model for evaluation of malaria vaccine candidates, given its susceptibility to experimental infection with the human malaria parasites Plasmodium falciparum and P. vivax. The present study examined the in vitro proliferative response of peripheral blood mononuclear cells (PBMCs) isolated from Aotus monkeys, utilizing a wide range of mitogens. Results presented herein demonstrate that the in vitro proliferative response of PBMCs from the Aotus sp. is quite variable from monkey to monkey for each of the mitogens assessed. PBMCs from the Aotus monkey exhibited a delayed kinetic proliferative response and, particularly, a different sensitivity to proliferation in response to various concentrations of Phytohemagglutinin-P and favin lectins, the phorbol ester Phorbol myristate acetate and the calcium ionophore ionomycin. Altogether, our findings are consistent with the conclusion that the in vitro proliferative response of PBMCs from the Aotus differ in their activation requirements compared with PBMCs from humans.

  • immunoglobulin kappa light chain v j and c gene sequences of the owl monkey Aotus nancymaae
    Immunogenetics, 2000
    Co-Authors: O L Diaz, Manuel Elkin Patarroyo, Raul Rodriguez, Claudia Daubenberger, Martin Naegeli, Alberto Moreno, Gerd Pluschke
    Abstract:

    Sequences of Aotus nancymaae immunoglobulin kappa light-chain rearrangements were analyzed after reverse transcription polymerase chain reaction. Among 22 in-frame rearrangements analyzed, 12 IGKV genes belonging to the families 1, 2, or 3 were identified. Aotus counterparts for all five human IGKJ genes were found. The identity of the deduced human and Aotus amino acid sequences was between 83% and 92% for junctional regions and 74% for the constant region. Sequence comparisons between rearrangements indicated that somatic mutations, the addition of nongermline-encoded nucleotides, and exonuclease trimming contribute to the generation of diversity of Aotus immunoglobulin kappa chains. The high identity of Aotus and human IGK genes is comparable to that of T-cell receptor genes and further supports the proposal to use the Aotus Plasmodium falciparum infection model for the evaluation of malaria vaccine candidates.

Raul Rodriguez - One of the best experts on this subject based on the ideXlab platform.

  • Owl monkey MHC-DRB exon 2 reveals high similarity with several HLA-DRB lineages
    Immunogenetics, 2006
    Co-Authors: Carlos F Suarez, Juan E. Baquero, Esperanza Trujillo, Manuel E. Patarroyo, Mónica Estupiñán, Carlos Parra, Raul Rodriguez
    Abstract:

    One hundred and ten novel MHC-DRB gene exon 2 nucleotide sequences were sequenced in 96 monkeys from three owl monkey species (67 from Aotus nancymaae , 30 from Aotus nigriceps and 13 from Aotus vociferans ). Owl monkeys, like humans, have high MHC-DRB allele polymorphism, revealing a striking similarity with several human allele lineages in the peptide binding region and presenting major convergence with DRB lineages from several Catarrhini (humans, apes and Old World monkeys) rather than with others New World monkeys (Platyrrhini). The parallelism between human and Aotus MHC-DRB reveals additional similarities regarding variability pattern, selection pressure and physicochemical constraints in amino acid replacements. These observations concerning previous findings of similarity between the Aotus immune system molecules and their human counterparts affirm this specie’s usefulness as an excellent animal model in biomedical research.

  • Proliferative response of peripheral blood lymphocytes to mitogens in the owl monkey Aotus nancymae.
    Journal of Medical Primatology, 2003
    Co-Authors: Alberto Pinzón-charry, Jean Paul Vernot, Raul Rodriguez, Manuel Elkin Patarroyo
    Abstract:

    : The new world primate Aotus sp. has been recommended by the World Health Organization as a model for evaluation of malaria vaccine candidates, given its susceptibility to experimental infection with the human malaria parasites Plasmodium falciparum and P. vivax. The present study examined the in vitro proliferative response of peripheral blood mononuclear cells (PBMCs) isolated from Aotus monkeys, utilizing a wide range of mitogens. Results presented herein demonstrate that the in vitro proliferative response of PBMCs from the Aotus sp. is quite variable from monkey to monkey for each of the mitogens assessed. PBMCs from the Aotus monkey exhibited a delayed kinetic proliferative response and, particularly, a different sensitivity to proliferation in response to various concentrations of Phytohemagglutinin-P and favin lectins, the phorbol ester Phorbol myristate acetate and the calcium ionophore ionomycin. Altogether, our findings are consistent with the conclusion that the in vitro proliferative response of PBMCs from the Aotus differ in their activation requirements compared with PBMCs from humans.

  • Sequence and diversity of DRB genes of Aotus nancymaae, a primate model for human malaria parasites.
    Immunogenetics, 2000
    Co-Authors: J. Javier Nino-vasquez, Raul Rodriguez, Alberto Moreno, Gerd Pluschke, Manuel E. Patarroyo, Denise Vogel, Claudia Daubenberger
    Abstract:

    The New World primate Aotus nancymaae is susceptible to infection with the human malaria parasite Plasmodium falciparum and Plasmodium vivax and has therefore been recommended by the World Health Organization as a model for evaluation of malaria vaccine candidates. We present here a first step in the molecular characterization of the major histocompatibility complex (MHC) class II DRB genes of Aotus nancymaae (owl monkey or night monkey) by nucleotide sequence analysis of the polymorphic exon 2 segments. In a group of 15 nonrelated animals captivated in the wild, 34 MHC DRB alleles could be identified. Six allelic lineages were detected, two of them having human counterparts, while two other lineages have not been described in any other New World monkey species studied. As in the common marmoset, the diversity of DRB alleles appears to have arisen largely by point mutations in the β-pleated sheets and by frequent exchange of fixed sequence motifs in the α-helical portion. Pairs of alleles differing only at amino acid position b86 by an exchange of valine to glycine are present in Aotus, as in humans. Essential amino acid residues contributing to MHC DR peptide binding pockets number 1 and 4 are conserved or semiconserved between HLA-DR and Aona-DRB molecules, indicating a capacity to bind similar peptide repertoires. These results support fully our using Aotus monkeys as an animal model for evaluation of future subunit vaccine candidates.

  • immunoglobulin kappa light chain v j and c gene sequences of the owl monkey Aotus nancymaae
    Immunogenetics, 2000
    Co-Authors: O L Diaz, Manuel Elkin Patarroyo, Raul Rodriguez, Claudia Daubenberger, Martin Naegeli, Alberto Moreno, Gerd Pluschke
    Abstract:

    Sequences of Aotus nancymaae immunoglobulin kappa light-chain rearrangements were analyzed after reverse transcription polymerase chain reaction. Among 22 in-frame rearrangements analyzed, 12 IGKV genes belonging to the families 1, 2, or 3 were identified. Aotus counterparts for all five human IGKJ genes were found. The identity of the deduced human and Aotus amino acid sequences was between 83% and 92% for junctional regions and 74% for the constant region. Sequence comparisons between rearrangements indicated that somatic mutations, the addition of nongermline-encoded nucleotides, and exonuclease trimming contribute to the generation of diversity of Aotus immunoglobulin kappa chains. The high identity of Aotus and human IGK genes is comparable to that of T-cell receptor genes and further supports the proposal to use the Aotus Plasmodium falciparum infection model for the evaluation of malaria vaccine candidates.

  • Sequence and diversity of T-cell receptor alpha V , J , and C genes of the owl monkey Aotus nancymaae
    Immunogenetics, 1999
    Co-Authors: William Vecino, Raul Rodriguez, Manuel A Patarroyo, Claudia Daubenberger, Alberto Moreno, Gerd Pluschke
    Abstract:

    We cloned and sequenced TcR alpha chain cDNA of three healthy Aotus nancymaae monkeys. Fifteen different TRAJ segments and 9 different TRAV genes were identified in the 29 rearrangements analyzed. As expected from the greater phylogenetic distance, A. nancymaae TRA gene sequences diverged more from the human sequences than those of the chimpanzee or the rhesus macaque. However, no Aotus TRAJ segment or TRAV gene was found which lacked a human counterpart. These counterparts were AJ02, AJ05, AJ09, AJ15, AJ22, AJ23, AJ28, AJ30, AJ32, AJ34, AJ37, AJ40, AJ42, AJ45, AJ52 and AV2S1, AV2S3, AV3S1, AV8S1, AV12S1, AV15S1, ADV21S1/DV5, AV22S1S and AV23S1, respectively. In most cases the identity of amino acid sequences between corresponding Aotus and human genes was greater than 80%. This marked conservation of TRA gene sequences indicates a close structural relationship of Aotus and human TcR and demonstrates that the TcR repertoire in primates is remarkably stable. The results support the concept of using Aotus monkeys, which are susceptible to infection with the human malaria parasite Plasmodium falciparum, as an animal model for the evaluation of molecularly defined malaria vaccine candidates.

Gerald H. Jacobs - One of the best experts on this subject based on the ideXlab platform.

  • Mutational changes in S-cone opsin genes common to both nocturnal and cathemeral Aotus monkeys.
    American Journal of Primatology, 2007
    Co-Authors: David H. Levenson, Eduardo Fernandez-duque, Sian Evans, Gerald H. Jacobs
    Abstract:

    Aotus is a platyrrhine primate that has been classically considered to be nocturnal. Earlier research revealed that this animal lacks a color vision capacity because, unlike all other platyrrhine monkeys, Aotus has a defect in the opsin gene that is required to produce short-wavelength sensitive (S) cone photopigment. Consequently, Aotus retains only a single type of cone photopigment. Other mammals have since been found to show similar losses and it has often been speculated that such change is in some fashion tied to nocturnality. Although most species of Aotus are indeed nocturnal, recent observations show that Aotus azarai, an owl monkey species native to portions of Argentina and Paraguay, displays a cathemeral activity pattern being active during daylight hours as frequently as during nighttime hours. We have sequenced portions of the S-cone opsin gene in A. azarai and Aotus nancymaae, the latter a typically nocturnal species. The S-cone opsin genes in both species contain the same fatal defects earlier detected for Aotus trivirgatus. On the basis of the phylogenetic relationships of these three species these results imply that Aotus must have lost a capacity for color vision early in its history and they also suggest that the absence of color vision is not compulsively linked to a nocturnal lifestyle. Am. J. Primatol. 69:757–765, 2007. © 2007 Wiley-Liss, Inc.

  • Photopigments and color vision in the nocturnal monkey,Aotus
    Vision Research, 1993
    Co-Authors: Gerald H. Jacobs, Michael A. Crognale, Jay Neitz, Jess F. Deegan, Maureen Neitz
    Abstract:

    The owl monkey (Aotus tridrgutus) is the only nocturnal monkey. The photopigments of Aotus and the relationship between these photopigments and visual discrimination were examined through (1) an analysis of the tlicker photometric electroretinogram (ERG), (2) psychophysical tests of visual sensitivity and color vision, and (3) a search for the presence of the photopigment gene necessary for the production of a short-wavelength sensitive (SWS) photopigment. Roth electrophysiological and behavioral measurements indicate that in addition to a rod photopigment the retina of this primate contains only one other photopigment type-a cone pigment having a spectral peak cu 543 nm. Earlier results that suggested these monkeys can make crude color discriminations are interpreted as probably resulting from the joint exploitation of signals from rods and cones. Although Aotus has no functional SWS photopigment, hybridization analysis shows that A&us has a pigment gene that is highly homologous to the human SWS photopigment gene. Aotus trivirgatus Cone photopigments Monkey color vision Monochromacy Photopigment genes Evolution of color vision