Identification of postentry restrictions to Mason-Pfizer monkey virus infection in New World monkey cells

TRIM5α has been shown to be a major postentry determinant of the host range for gammaretroviruses and lentiviruses and, more recently, spumaviruses. However, the restrictive potential of TRIM5α against other retroviruses has been largely unexplored. We sought to determine whether or not Mason-Pfizer monkey virus (M-PMV), a prototype betaretrovirus isolated from rhesus macaques, was sensitive to restriction by TRIM5α. Cell lines from both Old World and New World primate species were screened for their susceptibility to infection by vesicular stomatitis virus G protein pseudotyped M-PMV. All of the cell lines tested that were established from Old World primates were found to be susceptible to M-PMV infection. However, fibroblasts established from three New World monkey species specifically resisted infection by this virus. Exogenously expressing TRIM5α from either tamarin or squirrel monkeys in permissive cell lines resulted in a block to M-PMV infection. Restriction in the resistant cell line of spider monkey origin was determined to occur at a postentry stage. However, spider monkey TRIM5α expression in permissive cells failed to restrict M-PMV infection, and interference with endogenous TRIM5α in the spider monkey fibroblasts failed to relieve the block to infectivity. Our results demonstrate that TRIM5α specificity extends to betaretroviruses and suggest that New World monkeys have evolved additional mechanisms to restrict the infection of at least one primate betaretrovirus.     

Emigration in a black howling monkey group

From August 1989 to January 1994, we monitored the age-sex composition of a small group of Alouatta carayainhabiting a 2-ha seminatural forest. During this period we observed seven cases of emigration: four by juvenile females, two by subadult females, and one by a subadult male. Five subjects formed a new bisexual group living in a marginal 0.3-ha portion of the site. Four of them died. Male changes occurred and seem to be followed by infanticides.     

Y-chromosomal red-green opsin genes of nocturnal New World monkey

The X-chromosomal locality of the red-green-sensitive opsin genes has been the norm for all mammals and is essential for color vision of higher primates. Owl monkeys (Aotus), a genus of New World monkeys, are the only nocturnal higher primates and are severely color-blind. We demonstrate that the owl monkeys possess extra red-green opsin genes on the Y-chromosome. The Y-linked opsin genes were found to be extremely varied, in one male appearing to be a functional gene and in other males to be multicopy pseudogenes. These Y-linked opsin genes should offer a rare opportunity to study the evolutionary fate of genes translocated to the Y chromosome.     

Immature and adult langur monkey (Presbytis entellus) males: Infant-initiated adoption in a colony group

This paper focuses on interactions of an immature male langur monkey (Presbytis entellus) with an adult male in a captive social group. During his mother's 2-week absence, an 8-month-old male actively sought and received care from two adults, including an adult male. The interactions of the 2 males are compared with the behavior of 12 other adult male-immature male pairs to illustrate variability in male-male relations for a species in which adult male-young interactions are reported to be minimal and in which males normally spend portions of their lives in all-male groups.     

Sex change towards female in dying Acer rufinerve trees

BACKGROUND AND AIMS: Sex changes within the genus Acer (Aceraceae) may occur because of associations of sex expression and plant health. In this study, a natural population of Acer rufinerve was monitored to clarify the sex change patterns, the relationship between sex expression and plant health, and the causal environmental conditions that precede sex changes. METHODS: Sex expression, growth rate and mortality of A. rufinerve trees in a natural population were monitored from 1992 to 1997. KEY RESULTS: Three types of sex expression were observed among A. rufinerve: male, female and bisexual. Among the three types of sex expression, sex changes occurred in all directions. In the growing season of 1994, precipitation was reduced. Stem growth rate decreased and mortality was high in 1994. In the spring of 1995, a drastic sex change from male to female or to bisexual occurred. As a result, the sex ratio became female-biased in 1995, although it had been male-biased from 1992 to 1994. In 1996 and 1997, the proportion of males in the population increased, partly as a result of female mortality and partly as a result of female-to-male sex changes. Sex expression of A. rufinerve was associated with their growth rate and mortality. The growth rate decreased for trees whose sex changed from male to female or to bisexual, and increased for trees whose sex changed from female to male or to bisexual. Dead trees reproduced as females before they died, except for those that died as males in 1994. CONCLUSIONS: One explanation for the sex change towards increasing femaleness for this A. rufinerve population in 1995 was the deterioration of plant health in the previous growing season, because of reduced precipitation. Sex changes of unhealthy and dying A. rufinerve towards femaleness may facilitate re-occupancy by offspring in gaps created by the death of A. rufinerve trees.     

The daily activity rhythm in a troop of wild Japanese monkey

An assessment of the daily activity rhythm of wild Japanese monkeys was tried both from the calculation of the proportion that each activity occupied in the total activities and the “nomadograph,” representing temporary change in the pace of the daily movement. Seasonal and day-to-day changes are recognized in the daily activity rhythm of the troop of wild Japanese monkeys. It seems that seasonal change in the daily activity rhythm corresponds to the seasonal fluctuation of food supply and atmospheric temperature. From autumn to early winter, when much food is available, a clear-cut pattern of activity emerges; namely, three intensive feeding periods are recognized in a day. Moreover, day-to-day variation in the activity rhythm is fairly small and the activity pattern thus becomes standardized. In winter, when least food is available, activity of monkeys drops to the lowest level of the year. Day-to-day variation in the activity rhythm is great. Two to four intensive feeding periods in a day are recognized. In early spring and summer, when food supply is rather scarce, there exist two to three intensive feeding periods in a day. During the heat of the day in summer, activity of monkeys is conspicuously low.     

Lineage-specific diversification of killer cell Ig-like receptors in the owl monkey,a New World primate

Killer cell Ig-like receptors (KIRs) modulate the cytotoxic effects of natural killer cells. In primates, the KIRs are highly diverse as a consequence of variation in gene content, alternative domain composition, and loci polymorphism. We analyzed a bacterial artificial chromosome (BAC) clone draft sequence spanning the owl monkey KIR cluster. The draft sequence had seven ordered yet unconnected contigs containing six full-length and two partial gene models, flanked by the LILRB and FcAR framework genes. Gene models were predicted to encode KIRs with inhibitory, activating, or dual functionality. Four gene models encoded three Ig domain receptors, while three others encoded molecules with four Ig domains. The additional domain resulted from an insertion in tandem of a 2,101 bp fragment containing the last 289 bp of intron 2, exon 3, and intron 3, resulting in molecules with two D0 domains. Re-screening of the owl monkey BAC library and sequencing of partial cDNAs from an owl monkey yielded five additional KIRs, four of which encoded receptors with short cytoplasmic domains with premature stop codons due to either a single nucleotide substitution or deletion or the absence of exon 8. Phylogenetic analysis by domains showed that owl monkey KIRs were monophyletic, clustering independently from other primate KIR lineages. Retroelements found in introns, however, were shared by KIRs from different primate lineages. This suggests that the owl monkey inherited a KIR cluster with a rich history of exon shuffling upon which positive selection for ligand binding operated to diversify the receptors in a lineage-specific fashion. Nucleotide sequence data reported are available in the GenBank database under accession numbers FJ154791–5.     

Retropositional events consolidate the branching order among New World monkey genera

Due to contradicting relationships obtained from various morphological and genetic studies, phylogenetic relationships among New World monkey genera are highly disputed. In the present study, we analyzed the presence/absence pattern of 128 SINE integrations in all New World monkey genera. Among them, 70 were specific for only a single genus, whereas another 18 were present in all New World monkey genera. The 40 remaining insertions were informative to elucidate phylogenetic relationships among genera. Several of them confirmed the monophyly of the three families Cebidae, Atelidae and Pitheciidae as well as of the subfamily Callithrichinae. Further markers provided evidence for a sister grouping of Cebidae and Atelidae to the exclusion of Pitheciidae as well as for relationships among genera belonging to Callithrichinae and Atelidae. Although a close affiliation of Saimiri, Aotus and Cebus to Callithrichinae was shown, the relationships among the three genera remained unresolved due to three contradicting insertions.     

Distribution of affiliative behaviors among adult females within a group of wild patas monkeys in a nonmating,nonbirth season

The distribution of four affiliative behaviors (proximity within 3 m, allogrooming, contact calling, and co-night-resting) were examined in a group of wild patas monkeys (Erythrocebus patas) during a nonmating, nonbirth season. To a greater or lesser extent, dominance rank and kinship influenced these behaviors of the adult females. Since high-ranking females tended to exhibit some of these behaviors with high frequency, they were considered to be acting as the focus of affiliative behaviors and as the center for group cohesion. Furthermore, related adult females also tended to exhibit some of these behaviors with a high frequency toward one another, so that matrilineal kinship was also seen to be an important factor for group cohesion. In contrast, the harem male tended to exhibit these behaviors at a low frequency and/or had no affiliative partner for any of them. Thus, it appears that the social organization of the patas group is concentric, being composed of high-ranking females in the center, low-ranking females at the periphery, and the harem male at the distant periphery.     

Molecular cladistic markers in New World monkey phylogeny (Platyrrhini,Primates)

Transpositions of primate-specific Alu elements were applied as molecular cladistic markers in a phylogenetic analysis of South American primates. Seventy-four human and platyrrhine loci containing intronic Alu elements were PCR screened in various New World monkeys and the human outgroup to detect the presence of orthologous retrotransposons informative of New World monkey phylogeny. Six loci revealed size polymorphism in the amplification pattern, indicating a shared derived character state due to the presence of orthologous Alu elements confirmed by subsequent sequencing. Three markers corroborate (1) New World monkey monophyly and one marker supports each of the following callitrichine relationships: (2) Callithrix and Cebuella are more closely related to each other than to any other callitrichine, (3) the callitrichines form a monophyletic clade including Callimico, and (4) the next living relatives to the callitrichines are Cebus, Saimiri, and Aotus.     

Comparative large-scale propagation of retroviruses from Old World (Mason-Pfizer monkey virus) and New World (squirrel monkey virus) primates.

A cell culture method is described for the large-scale (50 to 150 1) production of Mason-Pfizer monkey virus and squirrel monkey virus, two primate retroviruses. Virus production was achieved with suspension cultures of chronically infected A204 human rhabdomyosarcoma cells harvested and clarified in the logarithmic stages of cell culture growth. Methods for the subsequent purification and concentration of virus material utilizing zonal centrifugation also are described. Applications of these methodologies resulted in products that afforded biochemical comparisons of these agents in a manner such that host cell-derived variations were minimized. These data indicated that high levels of production and efficient recovery and purification of virus material were achieved.     

New World monkey phylogeny based on X-linked G6PD DNA sequences

The Platyrrhini, or New World monkeys, are an infraorder of Primates comprised of 16 genera. Molecular phylogenetic analyses have consistently sorted these genera into three groups: the Pitheciidae (e.g., saki and titi monkeys), Atelidae (e.g., spider and howler monkeys), and Cebidae (e.g., night monkeys, squirrel monkeys, and tamarins). No consensus has emerged on the relationships among the three groups or within the Cebidae. Here, approximately 0.8 kb of newly generated intronic DNA sequence data from the X-linked glucose-6-phosphate dehydrogenase (G6PD) locus have been collected from nine New World monkey taxa to examine these relationships. These data are added to 1.3 kb of previously generated G6PD intronic DNA sequence data [Mol. Phylogenet. Evol. 11 (1999) 459]. Using distance and parsimony-based techniques, G6PD sequences provide support for an initial bifurcation between the Pitheciidae and the remaining platyrrhines, linking Atelidae and Cebidae as sister taxa. Bayesian methods provided a conflicting phylogeny with Atelidae as outgroup. Within the Cebidae, a sister relation between Aotus and the Cebus/Saimiri clade is favored by parsimony analysis, but not by other analyses. Potential reasons for the difficulty in resolving family level New World monkey phylogenetics are discussed.     

The leader's role in controlling aggressive behavior in a monkey group

An established group of pigtailed monkeys (Macaca nemestrina) was evaluated for aggressive behavior. The four highest ranking members of the group were removed one-by-one. Aggression was higher during all periods when the leader was absent and it decreased when he was returned. The leader male of aM. nemestrina group plays the major role in the control of aggression within the group.This research was supported by Public Health Service Grant No. FR 00166 from the National Institutes of Health.Ruth A. Bobbitt provided statistical consultation.