Amino acid sequences of the alpha and beta chains of adult hemoglobin of the slender loris, Loris tardigradus. (1/70)

alpha and beta chains from adult hemoglobin of the slender loris (Loris tardigradus) were isolated by Amberlite CG-50 column chromatography. After S-aminoethylation, both chains were digested with trypsin and the amino acid sequences of the tryptic peptides obtained were analyzed. Further, the order of these tryptic peptides in each chain was deduced from their homology with the primary structures of alpha and beta chains of human adult hemoglobin. Comparing the primary structures of the alpha and beta chains of adult hemoglobin of the slender loris thus obtained with those of adult hemoglobin of the slow loris, 4 amino acid substitutions in the alpha chains and 2 in the beta chains were recognized.  (+info)

The oestrous cycle of the brown lemur, Lemur fulvus. (2/70)

Examination of vaginal smears and observations of the colour and tumescence of the genitalia and discharge of mucus of 9 brown lemurs indicated that the oestrous cycle lasted for 30 days and that cycles occurred between September and July. The timing of cycles of females housed in visual isolation differed from that of females able to see other lemurs, indicating that the oestrous cycle in this species can be influenced by different housing conditions.  (+info)

TT virus infection in nonhuman primates and characterization of the viral genome: identification of simian TT virus isolates. (3/70)

Newly discovered TT virus (TTV) is widely distributed in human populations. To understand more about the relationship between TTV and its hosts, we tested 400 sera from various nonhuman primates for the presence of TTV DNA by PCR assay. We collected serum samples from 24 different species of nonhuman primates. TTV DNA was determined by PCR with primers designed from the 5'-end region of the TTV genome. Nucleotide sequencing and phylogenetic analysis of viral genomes were also performed. TTV DNA was detected in 87 of 98 (89%) chimpanzees and 3 of 21 (14%) crab-eating macaques. Nucleotide sequences of the PCR products obtained from both animals were 80 to 100% identical between two species. In contrast, the sequences differed from TTV isolates in humans by 24 to 33% at the nucleotide level and 36 to 50% at the amino acid level. Phylogenetic analysis demonstrated that all TTV isolates obtained from simians were distinct from the human TTV isolates. Furthermore, TTV in simians, but not in humans, was classified into three different genotypes. Our results indicate that TTV in simians represents a group different from, but closely related to, TTV in humans. From these results, we tentatively named this TTV simian TTV (s-TTV). The existence of the s-TTV will be important in determining the origin, nature, and transmission of human TTV and may provide useful animal models for studies of the infection and pathogenesis of this new DNA virus.  (+info)

Amino acid sequences of the alpha and beta chains of adult hemoglobin of the brown lemur, Lemur fulvus fulvus. (4/70)

Globin prepared from hemoglobin of the brown lemur (Lemur fulvus fulvus) was separated into alpha and beta chains by chromatography on a CM 52 column. The S-aminoethylated alpha and beta chains were each digested with trypsin and resulting peptides were isolated. The amino acid sequences of the tryptic peptides were established. The ordering of these peptides in the alpha and beta chains was deduced from the homology of their amino acid sequences with that of human adult hemoglobin. The primary structure of brown lemur hemoglobin thus obtained differs from that of human hemoglobin in 15 amino acids in the alpha chain and 26 in the beta chain.  (+info)

Alu elements support independent origin of prosimian, platyrrhine, and catarrhine Mhc-DRB genes. (5/70)

The primate major histocompatibility complex (Mhc) genes fall into two classes and each of the classes into several families. Of the class II families, the DRB family has a long and complex evolutionary history marked by gene turnover, rearrangement, and molecular convergence. Because the history is not easily decipherable from sequences alone, Alu element insertions were used as cladistic markers to support the surmised phylogenetic relationships among the DRB genes. Intron 1 segments of 24 DRB genes from five platyrrhine species and five DRB genes from three prosimian species were amplified by PCR and cloned, and the amplification products were sequenced or PCR-typed for Alu repeats. Three Alu elements were identified in the platyrrhine and four in the prosimian DRB genes. One of the platyrrhine elements (Alu50J) is also found in the Catarrhini, whereas the other two (Alu62Sc, Alu63Sc) are restricted to the New World monkeys. Similarly, the four prosimian elements are found only in this taxon. This distribution of Alu elements is consistent with the phylogeny of the DRB genes as determined from their intron 1 sequences in an earlier and the present study. It contradicts the exon 2-based phylogeny and thus corroborates the conclusion that the evolution of DRB exon 2 sequences is, to some extent, shaped by molecular convergence. Taken together, the data indicate that each of the assemblages of DRB genes in prosimians, platyrrhines, and catarrhines is derived from a separate ancestral gene.  (+info)

Opsin gene and photopigment polymorphism in a prosimian primate. (6/70)

A recent genetic investigation found some species of prosimian to have an opsin gene polymorphism [Nature 402 (1999) 36]. In the present study the functional implications of this finding were explored in a correlated investigation of opsin genes and spectral sensitivity measurements of a diurnal prosimian, Coquerel's sifaka (Propithecus verreauxi coquereli). Spectra recorded using electroretinogram (ERG) flicker photometry reveal a cone photopigment polymorphism paralleling an opsin gene polymorphism detected by molecular methods. This species has two middle-to-long-wavelength cone pigments with peak sensitivities of about 545 and 558 nm and a short-wavelength-sensitive cone with a peak at about 430 nm. The distribution of these pigments among animals predicts the presence of both dichromatic and trichromatic forms of color vision.  (+info)

Organization of seminiferous epithelium in primates: relationship to spermatogenic efficiency, phylogeny, and mating system. (7/70)

The succession in time and space of specific germ cell associations, denoted as spermatogenic stages, is a typical feature of mammalian spermatogenesis. The arrangement of these stages is either single stage (one spermatogenic stage per tubular cross-section) or multistage (more than one spermatogenic stage per tubular cross-section). It has been proposed that the single-stage versus multistage arrangement is related to spermatogenic efficiency and that the multistage arrangement is typical for hominids. In the present work, the arrangement of spermatogenic stages and the spermatogenic efficiency of 17 primate species, comprising Strepsirrhini (Prosimians: Lemuriformes, Lorisiformes), Platyrrhini (New World primates), Catarrhini (Old World primates), and Hominoidea (great apes and humans), were analyzed comparatively by quantitative histological and flow cytometric means. We found a predominant single-stage tubular organization in the Strepsirrhini, indicating that the single-stage form represents the ancestral state. The highest degree of multistage complexity was found in Hominoidea (except orangutan) and in Platyrrhini, but not in Catarrhini. Hence, no direct relationship between single-stage/multistage tubular topography and phylogeny could be established across primates. In fact, the tubule arrangement seen in Platyrrhini and Catarrhini primates is the reverse of what might be expected from phylogeny. Interestingly, spermatogenic efficiency was similar in all species. We found no correlation between single-stage/multistage arrangement and spermatogenic efficiency or mating system. We speculate that the presence of a single-stage/multistage organization might simply reflect germ cell clonal size. Our findings further indicate that sperm competition in primates is not reflected at the level of testicular function.  (+info)

Muscles of facial expression in Otolemur, with a comparison to lemuroidea. (8/70)

Gross and histologic aspects of facial expression muscles are presented here for Otolemur spp. (suborder Prosimii, family Lorisidae) and are compared with those of lemuroids. Muscles of facial expression are involved in social signaling among primates, and are a primary means by which close-proximity nonverbal communication is achieved. These muscles have been well described in catarrhines and many of the lemuroids; however, their arrangement is not well known in the lorisids. In the present study we examined muscles of facial expression in Otolemur by dissecting preserved faces. The arrangement and appearance of the muscles were noted, and samples were gathered from each muscle for histologic processing. The results showed 17 muscles of facial expression in Otolemur, as compared to seven reported in previous studies. Histologically, muscles of the ear region were arranged in tight, dense fascicles, while muscles of the orbital region were arranged more loosely. Grossly, the facial expression muscles in Otolemur were very similar in morphology and attachments to those in the lemuroids, with some differences in the ear region. Otolemur garnettii had several muscles that appeared to be more robust than in the larger O. crassicaudatus. This may be due to dietary and/or social differences between the species. In previous studies it was concluded that, relative to lemuroids, Otolemur has a primitive arrangement of facial expression muscles. The current results do not support that conclusion, and in fact support a far greater similarity between Otolemur and lemuroids in general. These results underscore the need for a reexamination of facial musculature in prosimians in general, and may have taxonomic value as regards the position of Otolemur with lemuroids and other galagos.  (+info)

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