Evidence linking APOBEC3B genesis and evolution of innate immune antagonism by gamma-herpesvirus ribonucleotide reductases.

Viruses have evolved diverse mechanisms to antagonize host immunity such as direct inhibition and relocalization of cellular APOBEC3B (A3B) by the ribonucleotide reductase (RNR) of Epstein-Barr virus. Here, we investigate the mechanistic conservation and evolutionary origin of this innate immune counteraction strategy. First, we find that human gamma-herpesvirus RNRs engage A3B via largely distinct surfaces. Second, we show that RNR-mediated enzymatic inhibition and relocalization of A3B depend upon binding to different regions of the catalytic domain. Third, we show that the capability of viral RNRs to antagonize A3B is conserved among gamma-herpesviruses that infect humans and Old World monkeys that encode this enzyme but absent in homologous viruses that infect New World monkeys that naturally lack the A3B gene. Finally, we reconstruct the ancestral primate A3B protein and demonstrate that it is active and similarly engaged by the RNRs from viruses that infect humans and Old World monkeys but not by the RNRs from viruses that infect New World monkeys. These results combine to indicate that the birth of A3B at a critical branchpoint in primate evolution may have been a driving force in selecting for an ancestral gamma-herpesvirus with an expanded RNR functionality through counteraction of this antiviral enzyme.

Energy balance but not competitive environment corresponds with allostatic load during development in an Old World monkey.

Primates develop slowly relative to their body size, a pattern posited to result from ecological risk aversion. Little is known, however, about how energy balance contributes to allostatic load in juveniles. Using data collected over 8 consecutive months, we examined variation in energy balance (as measured by urinary C-peptide) and how energy balance, life history status, and social competition related to allostatic load (as measured by deviation from baseline fecal glucocorticoid metabolites, dfGCs) in 41 wild juvenile blue monkeys from 3 social groups. Juvenile energy balance was higher among females, older juveniles, when ripe fruit was more available, and when rainfall was lower. Energy balance, but not life history or competitive environments, predicted dfGC concentrations, such that juveniles generally had lower mean dfGCs when they had higher energy balance. An additional exploratory analysis of how dfGCs relate to social strategies revealed that subjects had lower dfGCs when they groomed less, and played more. Time spent grooming interacted with energy balance in predicting dfGC concentrations, so that individuals that groomed more actually had higher dfGCs when they had higher energy balance. Together these results reveal that energetic deficiencies are a true ecological risk factor in blue monkeys, and suggest that navigating the social environment via overt affiliative behavior is potentially both a stress-relieving and stress-inducing endeavor during development.

Fluorescent image analysis of HIV-1 and HIV-2 uncoating kinetics in the presence of old world monkey TRIM5α.

Uncoating of Human Immunodeficiency Virus type 1 (HIV-1) and type 2 (HIV-2) conical cores is an important early step for establishment of infection. In Old World Monkey (OWM) cells, the TRIM5α cellular factor potently suppresses an early step of infection by HIV-1. Previously, biochemical studies using whole cell lysates of infected cells revealed that OWM TRIM5α accelerates the uncoating of HIV-1, leading to premature reverse transcription. In the present study, we re-evaluated uncoating kinetics of HIV-1 in the presence of OWM TRIM5α by using an in situ uncoating assay, which allowed us to differentiate productive HIV-1 entry from simple (non-productive) endocytosis. Results showed that the uncoating kinetics of HIV-1 was indeed accelerated in the presence of OWM TRIM5α. Furthermore, we adapted an in situ uncoating assay to HIV-2, which showed wide variations in TRIM5α sensitivity among different isolates. HIV-2 isolate GH123, whose infectivity was suppressed by cynomolgus monkey (CM) TRIM5α, showed accelerated uncoating in the presence of CM TRIM5α. In contrast, mutant HIV-2 ASA, whose infectivity was unaltered by CM TRIM5α, showed no change in uncoating kinetics in the presence of CM TRIM5α. These results confirmed and further extended the previous notion that accelerated uncoating is associated with restriction activity of TRIM5α against lentiviruses.

Prefrontal-enriched SLIT1 expression in Old World monkey cortex established during the postnatal development.

To elucidate the molecular basis of the specialization of cortical architectures, we searched for genes differentially expressed among neocortical areas of Old World monkeys by restriction landmark cDNA scanning . We found that mRNA of SLIT1, an axon guidance molecule, was enriched in the prefrontal cortex but with developmentally related changes. In situ hybridization analysis revealed that SLIT1 mRNA was mainly distributed in the middle layers of most cortical areas, robustly in the prefrontal cortex and faintly in primary sensory areas. The lowest expression was in the primary visual area. Analyses of other SLIT (SLIT2 and SLIT3) mRNAs showed preferential expression in the prefrontal cortex with a distinct laminar pattern. By contrast, the receptor Roundabout (ROBO1 and ROBO2) mRNAs were widely distributed throughout the cortex. Perinatally, SLIT1 mRNA was abundantly expressed in the cortex with modest area specificity. Downregulation of expression initially occurred in early sensory areas around postnatal day 60 and followed in the association areas. The prefrontal area-enriched SLIT1 mRNA expression results from a relatively greater attenuation of this expression in the other areas. These results suggest that its role is altered postnatally and that this is particularly important for prefrontal connectivity in the Old World monkey cortex.

Differential expression of GLUT2 in pancreatic islets and kidneys of New and Old World nonhuman primates.

Diabetes is a growing public health concern, and animal models of this disease are necessary for a full understanding of disease pathogenesis, progression, clinical sequelae, and treatment options. In particular, nonhuman primate models of diabetes are important because of their close genetic relationship to humans. Although numerous Old World primate models have been described, few studies have examined the possibility of using New World monkeys as an animal model for this disease. Streptozotocin (STZ) is a common diabetogenic drug that selectively destroys beta cells after uptake via the GLUT2 glucose transporter. Induction of diabetes using STZ was attempted in common marmosets (Callithrix jacchus). These animals showed increases in blood glucose consistent with diabetes only at STZ doses markedly greater than those used in other primate species. Additionally, all animals showed pathological evidence of acute renal and liver toxicity secondary to the treatment. In a subsequent comparative study of various nonhuman primates, GLUT2 immunostaining in pancreatic islets was used as a marker for sensitivity to STZ. Immunostaining of islets from a variety of nonhuman primate species indicated a reduced expression of pancreatic GLUT2 in New compared with Old World monkeys; this finding explains their resistance to diabetic induction with STZ. Furthermore, there were age-dependent differences in GLUT2 expression, with aged and infant macaques showing reduced expression. We conclude that New World monkeys are an inappropriate model for diabetes induction with STZ and that, with all primate species, it is important to consider the animals' age before diabetic induction with STZ is attempted.

Restriction of foamy viruses by primate Trim5alpha.

Foamy viruses (FVs) are unconventional retroviruses with a replication strategy that is significantly different from orthoretroviruses and bears some homology to that of hepadnaviruses. Although some cellular proteins, such as APOBEC3, have been reported to block FVs, no restriction by Trim5alpha has been described to date. The sensitivity of three FV isolates of human-chimpanzee or prototypic (PFV), macaque (SFVmac), and feline (FFV) origin to a variety of primate Trim5alphas was therefore tested. PFV and SFVmac were restricted by Trim5alphas from most New World monkeys, but not from other primates, whereas FFV-based vectors were restricted by Trim5alphas from the great apes gorilla and orangutan. Trim5alphas from Old World monkeys did not restrict any FV isolate tested. Capuchin Trim5alpha was unique, as it restricted SFVmac and FFV but not PFV. Trim5alpha specificity for FVs was determined by the B30.2 domain, interestingly involving, in some instances, the same residues of the variable regions previously implicated as major determinants for human immunodeficiency virus type 1 restriction. FVs with chimeric Gags were made to map the viral determinants of sensitivity to restriction. The N-terminal half of the Gag molecule was found to contain the regions that control susceptibility. This region most likely corresponds to the capsid of conventional retroviruses. Due to their unique replication strategy, FVs should provide a valuable new system to examine the mechanism of retroviral restriction by Trim5alpha.

Comparative energetics of primate fetal growth.

Among the primates, Homo sapiens has evolved a life history which includes long gestation, relatively slow growth to reproductive maturity, and large body size. While the slow growth rate may be linked to the energetic demands of having a large brain, there are other important morphological and physiological linkages that may be adaptive, including the development of significant fat stores with which to buffer against episodic and periodic energetic stress. In this comparative analysis of the energetic burden of pregnancy among primates (including humans), the daily energy investment in the development of neonatal tissue is modeled. During pregnancy, larger primates, notably the Hominidae, invest a smaller proportion of their maternal daily nonmaintenance energy budget in fetal tissue with increasing energy budget, allowing diverse adaptations, including foraging strategies which include folivory and mixed patterns of food getting, and meat consumption. Humans have a similar proportion of maternal daily nonmaintenance energy budget invested in fetal tissue with increasing energy budget to other apes and have a diet which is of much higher quality than predicted for body size and metabolic needs. The combination of high diet quality and low proportion of maternal daily nonmaintenance energy budget invested in fetal tissue allows greater brain size relative to body weight at birth compared with all other primates, apart from chimpanzees, and higher birthweight and body fatness at birth for a given body size than other primate species.

The primary structure of langur (Presbytis entellus) pancreatic ribonuclease: adaptive features in digestive enzymes in mammals.

The primary structure of pancreatic ribonuclease from langur (Presbytis entellus) has been determined. This sequence differs from that of human pancreatic ribonuclease at 14 (11%) of the amino acid positions. Eight of these 14 differences involve changes of charge, with the langur enzyme having five fewer positive charges than the human enzyme. The difference in charge between human and langur ribonuclease may be an adaptation to the different requirements for a nondigestive and a digestive role, respectively. A number of similarities in expression, gene duplications, and properties between mammalian ribonucleases and lysozymes have been observed, indicating similar adaptations in both enzyme systems.

Immunoperoxidase localization of prostatic inhibin peptide in human, monkey, dog, and rat prostates.

A comparative study on the localization of prostatic inhibin peptide was carried out by the immunoperoxidase technique in prostates of humans, bonnet and langur monkeys, marmosets, dogs, and rats. A positive reaction was observed in the prostatic epithelial cells of humans, in all three species of monkeys, and in the rat, while the dog prostate did not exhibit any reaction. These observations indicate a close immunological similarity among human, monkey, and rat prostatic inhibin peptides.

Localization of plutonium retention in the small intestine of the neonatal rat, guinea pig, baboon and macaca after Pu-citrate ingestion.

The retention of Pu-citrate in the gastrointestinal wall was compared at similar post ingestion times after ingestion at 2 days of age by rats and guinea pigs and at 1 to 34 days by neonatal primates. The small intestine was the main site of the Pu retention in all species. In rats and primates, most of the Pu was retained in the distal ileum, whereas in guinea pigs it was more homogeneously distributed. In the rats, Pu was retained in the epithelial cells on villi, but in the guinea pigs and primates it was confined to the macrophages under the epithelial cells in the lacteal region.

Diminished internalization and action of 1,25-dihydroxyvitamin D3 in dermal fibroblasts cultured from New World primates.

We investigated the occurrence of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]-resistant osteomalacia in the New World primate colony of Saguinus imperator at the Los Angeles Zoo. The mean serum concentration of 1,25-(OH)2D3 was elevated 5-fold in the New World primates compared to that in their Old World counterparts. The specific internalization of 0.6 nM [3H]1,25-(OH)2D3 by cultured dermal fibroblasts from New World primates was reduced 75% compared to that by cells from Old World primates or man. The decrease in hormone uptake resulted from a decrease in the number of high affinity intracellular binding sites for 1,25-(OH)2D3 and apparently caused a 90-95% reduction in 1,25-(OH)2D3-induced 25-hydroxyvitamin-D3-24-hydroxylase activity. There was no alteration in the capacity or avidity of New World primate serum for 1,25-(OH)2D3 compared to that of serum from Old World primates. These data suggest that the occurrence of vitamin D-resistant osteomalacia in New World primates is the result of decreased high affinity, receptor-mediated uptake of 1,25-(OH)2D3 by the target cell.

Density gradient characterization of the high density lipoproteins in cholesterol-fed hyper- and hyporesponding patas monkeys (Erythrocebus patas).

Diet-induced changes in high density lipoprotein (HDL) density and size were studied in patas monkeys. When the animals were switched from a moderate fat-low cholesterol diet to a high fat-high cholesterol (HFHC) diet, the plasma apoA-I levels increased initially in all of the animals. The apoA-I levels remained elevated in monkeys able to maintain their plasma cholesterol concentrations near basal levels (hyporesponders), but began to decrease in monkeys who became severely hypercholesterolemic (hyperresponders), reaching levels as low as 65-70% of their basal value by 24 weeks. The larger, lipid-rich HDL (HDL2) was shown by density gradient ultracentrifugation and gradient-PAGE (polyacrylamide gel electrophoresis) to be the HDL fraction responsible for these changes in apoA-I, completely accounting for the increase in apoA-I in hyporesponders and the decrease in apoA-I in hyperresponders. The HDL3 levels remained unchanged in hyporesponders but increased markedly in hyperresponders, partially compensating for the decrease of HDL2 in those animals. Gradient-PAGE showed the HDL3 to be heterogeneous, containing at least two populations of particles of the same density but differing significantly in size. The smaller of these HDL3 were most prominent in the HFHC-fed hyperresponders. These data show that nonhuman primate HDL is both physically and metabolically heterogeneous, and indicate that a high fat-high cholesterol diet-induced hypercholesterolemia severely depresses the HDL2 levels.

Mucosubstances in the cervix uteri of the Indian langur monkey, Presbytis entellus entellus (Dufrense).

Mucosubstances in the cervix uteri of the Indian langur monkey, Presbytis entellus entellus was studied during non-pregnancy, pregnancy and lactation. Cells of the cervical epithelium and glands elaborated neutral, sialo- and sulfomucins during non-pregnancy. The concentration of these mucins was low during early pregnancy but increased during late pregnancy. The concentration of mucins was higher during later part of pregnancy than during non-pregnant stage which decline during lactation. Significance of mucins in cervix uteri and probable hormonal control over their elaboration is discussed.

The myoglobin of primates X.

The amino acid sequences of skeletal muscle myoglobins from two old-world monkeys, Presbytis entellus and Erythrocebus patas, as well as one new-world monkey, Cebus apella wer inferred by homology of the tryptic and peptic peptides with the known sequence of human myoglobin and by selective dansyl-Edman degradation. These new sequences were examined phylogentically in conjunction with the 15 primate sequences already reported. It is clear that myoglobin evolution has been extremely conservative among cercopithecoid primates, so much so that the two surviving subfamilies cannot be distinguished using this protein.