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Muller N.,University of Gottingen | Ostner J.,University of Gottingen | Schulke O.,University of Gottingen | Walter L.,Leibniz Institute For Primatenforschung
American Journal of Primatology

The major histocompatibility complex (MHC) plays an important role in the immune response and may thus crucially affect an individual's fitness, relevant also for studies on evolutionary ecology and wildlife conservation. Detailed knowledge on the genomic organization, polymorphism and diversity of the MHC has a narrow taxonomic focus though and among macaques is only available for rhesus and long-tailed macaques-the species most commonly kept for biomedical research. The lack of data on wild populations is largely due to the difficulty of obtaining blood or tissue samples necessary for genotyping approaches. Here, we aimed at analyzing MHC-DRB from non-invasively collected fecal samples in wild Assamese macaques (Macaca assamensis), utilizing the MHC-DRB-STR (D6S2878) microsatellite marker. Due to the fecal DNA source incomplete genotypes occurred, which may be improved in the future by method refinement. We detected 28 distinct DRB-STR lengths in 43 individuals with individual genotypes containing 1-9 MHC-DRB-STRs and defined four haplotypes segregating between families in Mendelian fashion. Our results indicate that variability and diversity of MHC-DRB in Assamese macaques is comparable to that of other macaque species and importantly, that fecal samples can be used for non-invasive analysis of MHC genes after refinement of the applied methods, opening a number of opportunities for MHC research on natural populations. Am. J. Primatol. 9999:1-9, 2013. © 2013 Wiley Periodicals, Inc. Source

Aquino R.,National Major San Marcos University | Lopez L.,University of the Amazon | Garcia G.,University of the Amazon | Heymann E.W.,Leibniz Institute For Primatenforschung
Primate Conservation

Western Amazonia is one of the regions of the world with the highest terrestrial biodiversity. We conducted transect censuses between November and December 2012 in order to determine the diversity and the densities of primate populations, and their group sizes and habitat use in the Río Curaray region. During 610 km of transect surveys, we encountered 304 groups of 13 primate species. Woolly monkeys, Lagothrix poeppigii, were the most frequently observed (n = 49 sightings) and pygmy marmosets, Cebuella pygmaea, the least (n = 8). Population density was lowest for howler monkeys, Alouatta seniculus (9.8 individuals km-2) and saki monkeys, Pithecia aequatorialis (11.8 individuals km-2) and highest for squirrel monkeys, Saimiri macrodon (65.0 individuals km 2) and woolly monkeys (65.3 individuals km-2). Primate groups were most frequently encountered in "palmales de altura" (97 encounters of 12 species). In conclusion, the Río Curaray region harbors a very high diversity of primates, matching other sites in Amazonia and worldwide, and populations there are evidently healthy and well conserved. We recommend the creation of a protected area contiguous with the Yasuní National Park in Ecuador. Source

Walter L.,Leibniz Institute For Primatenforschung
Journal of Innate Immunity

Human natural killer (NK) cell receptors are known to be highly polymorphic, to show complex genetics and to be associated with susceptibility to a variety of immunological diseases. Nonhuman primates are used as important models of these diseases, yet the knowledge of nonhuman primate NK cell receptors and ligands is not as advanced as in humans. Recently published data indicated that diversity and polymorphism of NK cell receptors are similar between nonhuman primates and humans. Comparative genomics revealed instructive insights into the evolution and function of primate NK cell receptor genes and contributed to the understanding of how present-day NK cell receptors and their ligands have evolved. Here, I review the current knowledge of nonhuman primate NK cell receptors that interact with major histocompatibility complex class I proteins. Copyright © 2011 S. Karger AG, Basel. Source

Kanber D.,Universitatsklinikum Essen | Buiting K.,Universitatsklinikum Essen | Roos C.,Leibniz Institute For Primatenforschung | Gromoll J.,Universitatsklinikum Munster | And 3 more authors.

The human RB1 gene is imprinted due to a differentially methylated CpG island in intron 2. This CpG island is part of PPP1R26P1, a truncated retrocopy of PPP1R26, and serves as a promoter for an alternative RB1 transcript. We show here by in silico analyses that the parental PPP1R26 gene is present in the analysed members of Haplorrhini, which comprise Catarrhini (Old World Monkeys, Small apes, Great Apes and Human), Platyrrhini (New World Monkeys) and tarsier, and Strepsirrhini (galago). Interestingly, we detected the retrocopy, PPP1R26P1, in all Anthropoidea (Catarrhini and Platyrrhini) that we studied but not in tarsier or galago. Additional retrocopies are present in human and chimpanzee on chromosome 22, but their distinct composition indicates that they are the result of independent retrotransposition events. Chimpanzee and marmoset have further retrocopies on chromosome 8 and chromosome 4, respectively. To examine the origin of the RB1 imprint, we compared the methylation patterns of the parental PPP1R26 gene and its retrocopies in different primates (human, chimpanzee, orangutan, rhesus macaque, marmoset and galago). Methylation analysis by deep bisulfite sequencing showed that PPP1R26 is methylated whereas the retrocopy in RB1 intron 2 is differentially methylated in all primates studied. All other retrocopies are fully methylated, except for the additional retrocopy on marmoset chromosome 4, which is also differentially methylated. Using an informative SNP for the methylation analysis in marmoset, we could show that the differential methylation pattern of the retrocopy on chromosome 4 is allele-specific. We conclude that the epigenetic fate of a PPP1R26 retrocopy after integration depends on the DNA sequence and selective forces at the integration site. © 2013 Kanber et al. Source

Sinigalia E.,University of Padua | Alvisi G.,University of Padua | Alvisi G.,University of Bologna | Alvisi G.,University of Heidelberg | And 11 more authors.

During the replication of human cytomegalovirus (HCMV) genome, the viral DNA polymerase subunit UL44 plays a key role, as by binding both DNA and the polymerase catalytic subunit it confers processivity to the holoenzyme. However, several lines of evidence suggest that UL44 might have additional roles during virus life cycle. To shed light on this, we searched for cellular partners of UL44 by yeast two-hybrid screenings. Intriguingly, we discovered the interaction of UL44 with Ubc9, an enzyme involved in the covalent conjugation of SUMO (Small Ubiquitin-related MOdifier) to cellular and viral proteins. We found that UL44 can be extensively sumoylated not only in a cell-free system and in transfected cells, but also in HCMV-infected cells, in which about 50% of the protein resulted to be modified at late times post-infection, when viral genome replication is accomplished. Mass spectrometry studies revealed that UL44 possesses multiple SUMO target sites, located throughout the protein. Remarkably, we observed that binding of UL44 to DNA greatly stimulates its sumoylation both in vitro and in vivo. In addition, we showed that overexpression of SUMO alters the intranuclear distribution of UL44 in HCMV-infected cells, and enhances both virus production and DNA replication, arguing for an important role for sumoylation in HCMV life cycle and UL44 function(s). These data report for the first time the sumoylation of a viral processivity factor and show that there is a functional interplay between the HCMV UL44 protein and the cellular sumoylation system. © 2012 Sinigalia et al. Source

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