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PubMed1984

Human T-cell leukemia virus: transformation in vitro of nonhuman primate T-lymphocytes and experimental inoculation of nonhuman primates.

T-lymphocytes from three species of New World monkeys were susceptible to transformation in vitro with human T-cell leukemia virus. Marmoset T-lymphocytes transformed in vitro with HVS or HVA, T-lymphotropic herpesviruses of New World monkeys, were also transformed with HTLV resulting in doubly transformed T-cells. This finding may provide a potential model for investigating the possible interaction between a herpesvirus and T-lymphotropic retroviruses in the clinical condition AIDS.

Animals↗
PubMed1991

Thermal inactivation study of glutathione peroxidase and glutathione reductase activities in lenses of primates and non-primates.

Heat lability studies of glutathione peroxidase and glutathione reductase activities were conducted on rabbit, sheep, rat, human, galago, cat and rhesus monkey lens supernatants. These species represent five mammalian orders. Incubation periods were 10.0 minutes in duration, with temperatures ranging from 25-100 degrees C (depending on which enzyme was being investigated). Results obtained for glutathione peroxidase activity demonstrated nearly identical heat lability profiles for human and rhesus monkey lenses. Both species were extremely labile to heat, losing activity at 30 degrees C and becoming totally inactive at temperatures of 50 degrees C (rhesus monkey) and 55 degrees C (human). Their profiles were very dissimilar to those of the other five species investigated, providing evidence for the existence of an evolutionary break. Glutathione reductase activity was extremely stable under conditions of highly elevated temperature for all seven species investigated. The human lens enzyme, the most stable of the species, maintained nearly 100% of its original activity up to 65 degrees C. Lenticular glutathione reductase activity did not reach zero levels in any of the seven species until a temperature of at least 80 degrees C was attained.

Animals↗
PubMed1985

[The social structure of primates].

A comprehensive comparative study of the social structure of primates revealed: There is no social structure which can be considered typical and discriminative for primates. The varying social structures of the extant primate genera cannot be derived from each other: In contrast it seems that the basic, ancestral condition was that of solitary living animals, loosely aggregated. It can be assumed that the development to a gregarious society took place in two entirely different ways. In terms of primate phylogeny this different development can be shown for the prosimians as well as for the old world and new world monkeys as independently occurring processes. One way of behavioral specialization resulted in close pair bonds or in small family groups, whereas the other led to female groups. The presupposition for the forming of a society based on female groups is the close contact between the individuals and in addition to this, a remarkable social tolerance of females to each other. Social specializations which can be considered transitional from the basic condition are frequently found in prosimians. The kinds of social structures of the particular genera are in close relation to their taxonomic positions in the phylogenetic scala. The number of males in larger social groups of primates is substantially irrelevant as the groups are socially most dependent on the females. The protecting males are socially peripheral. The social units of most of the primate species are matrilocal and endure for several generations. In contrast, the social units of the gibbons and of the pongids are patrilocal and are established anew by the females in each generation. Consequently the social unit disintegrates on the death of the male. In all genera studied, male and female individuals present considerable behavioral differences which can be found even in juveniles. Primates are able to discriminate well known and confident individuals from other less confident; they prefer more confident individuals to less confident ones, and less confident to non-confident. As a consequence of this discriminative ability there is a clear preference for near when compared to distant relatives. The complexity of the social relations is brought about by this ability to discriminate combined with the longevity of primates. This is a characteristic and discriminative feature of the primate order. Dominance relations occur in every social group of primates. Linear hierarchies of dominance have been developed only once in prosimians (Lemur) and also once in simians (Cercopithecinae). Therefore, liner hierarchies are not typical for primates.

Age Factors↗
PubMed1987

Structure and evolution of primate cytochrome c oxidase subunit II gene.

The sequence of cytochrome oxidase subunit II (COII) mRNA from the cynomolgus macaque has been determined. Availability of the sequence from a non-human primate has allowed examination of the evolution of the COII gene and protein along the primate lineage. Comparison with existing protein and DNA sequences, combined with estimates of divergence derived from calculations designed to compensate for multiple mutation and reversion events, indicates that although the rate of fixation of nucleotide substitutions at silent sites is somewhat lower in primates than non-primates, the rate of fixation at replacement sites is 4-5-fold higher. The data also suggest that the rate of divergence at replacement sites along the primate lineage has not been uniform, but has decreased 2-2.5-fold since the higher primate branch point, in the absence of a comparable change in the rate substitution at silent sites. Both primate mRNAs differ from their non-primate homologues in having 3'-untranslated regions of 20-25 nucleotides. Examination of the monkey and human untranslated sequences suggests that these regions have evolved by duplication events occurring in both cases within 2-3 nucleotides following the translational stop codon. The primate mRNAs are also exceptional in that both can form stable stem and loop structures immediately preceding the postulated duplication site that may have played a role in facilitating the mutational events involved. Comparison of the human and monkey protein sequences has revealed regions conserved in primates that are significantly more hydrophobic than their non-primate counterparts. The possible effects of these alterations on the interaction between COII and cytochrome c are discussed.

Amino Acid Sequence↗
PubMed1986

The new world primates as animal models of glucocorticoid resistance.

Many New World primate species have greatly increased plasma cortisol concentrations, decreased plasma cortisol binding globulin capacity and affinity, marked resistance of the hypothalamic-pituitary-adrenal axis to suppression by dexamethasone, and no biological evidence of glucocorticoid excess. These primates also have high levels of circulating progesterone, estrogen, mineralocorticoid, androgen and vitamin D. The glucocorticoid target tissues that have been examined (circulating mononuclear lymphocytes and cultured skin fibroblasts) have normal concentrations of glucocorticoid receptors with decreased affinity for dexamethasone. Transformation of B-lymphocytes with the Epstein-Barr virus leads to glucocorticoid receptor induction that is less than that observed with cells from Old World primates. The receptor in these cells has a low affinity for dexamethasone. The low affinity leads to an increased loss of specific bound ligand during thermal activation. Meroreceptor generation is normal. The molecular weight of the receptor, determined by SDS-PAGE, is similar to that of Old World primates (approximately 92,000) and the activation pattern per se, examined in vitro by heating cytosol and performing phosphocellulose chromatography, appears similar to that of human controls. The ratios of nuclear to cytosolic hormone-receptor-complexes and of cytosolic activated to unactivated receptor complexes in intact cells are similar to Old World primates. Results from mixing studies do not support the hypothesis that a binding inhibitor(s) or a deficient cytosolic positive modifier(s) of binding underlies the findings in these primates. The New World primates, unlike men with the syndrome of primary cortisol resistance, have compensated for their condition with intra-adrenal and mineralocorticoid receptor adaptations. Thus, unlike Old World primates, cortisol in New World primates has only weak sodium-retaining potency because the aldosterone receptor has a low affinity for cortisol. The common element that would explain the apparent resistance to six steroid hormones in New World primates remains unknown.

Adrenal Glands↗
PubMed1981

Toward a molecular paleontology of primate genomes. I. The HindIII and EcoRI dimer families of alphoid DNAs.

Families of related, but nonidentical repetitive DNA sequences, termed the alphoid DNAs, have been identified and characterized in representative species from seven major primate Families. The sequences appear as old as the primate Order itself: they are found in a prosimian (lemur), in a New World monkey, and in all Old World primates examined, including man. The alphoid DNAs are uniquely primate sequences and they may represent the most abundant repetitive DNAs in the primate genome. - A classification scheme for two major families of alphoid DNAs is proposed that is based upon restriction enzyme analysis and Southern blotting with radioactive probes prepared from component alpha DNA (Maio, 1971) and from the human EcoRI dimer sequences (Manuelidis, 1976). The family of alphoid DNAs that hybridizes readily with component alpha is termed the HindIII family of alphoid DNAs. This family shows an almost universal distribution among present-day primates. The family of DNA sequences that hybridizes readily with the human EcoRI dimer probe is termed the EcoRI dimer family of alphoid DNAs. This family may be restricted to the great apes and man. The two probes permitted the discrimination of different, but related alphoid families in present-day primates. Multiple alphoid sequence families are found within the genomes of individual primates and the major primate taxa can be characterized by the representations of the various alphoid DNAs within their genomes. - An Appendix is presented (Brown et al., 1981) indicating that competition hybridization effects may influence the autoradiographic banding patterns, and hence, the interpretations of Southern filter-transfer hybridizations when dealing with related repetitive sequences such as the alphoid DNAs that are present in abundance in eukaryotic genomes.

Animals↗