Search

13 pages; International audience; The family Galagidae (African galagos or bushbabies) comprises five genera: EuoticusGray, 1872; GalagoGeoffroy Saint-Hilaire, 1796; GalagoidesSmith, 1833; OtolemurCoquerel, 1859; and SciurocheirusGray, 1872, none of which is regarded as monotypic, but some (Euoticus and Otolemur) certainly qualify as oligotypic. We argue for the recognition of a sixth genus, if the taxonomy is to reflect galagid evolution accurately. Genetic evidence has consistently demonstrated that the taxa currently referred to the genus Galagoides are not monophyletic but form two clades (a western and an eastern clade) that do not share an exclusive common ancestor; we review 20 years of genetic studies that corroborate this conclusion. Further, we compare vocalizations emitted by small-bodied galagids with proposed phylogenetic relationships and demonstrate congruence between these data sets. Morphological evidence, however, is not entirely congruent with genetic reconstructions; parallel dwarfing in the two clades has led to convergences in skull size and shape that have complicated the classification of the smaller species. We present a craniodental morphometric analysis of small-bodied galagid genera that identifies distinguishing characters for the genera and supports our proposal that five taxa currently subsumed under Galagoides (Galagoides cocos, Galagoides granti, Galagoides orinus, Galagoides rondoensis and Galagoides zanzibaricus) be placed in their own genus, for which we propose the name Paragalago.

Occupational exposure to anaesthetic gases is one of the major hazards to healthcare personnel. We evaluated the cytogenetic effects of chronic exposure to low concentrations of anaesthetic gases in operating theatres. The study included 21 anesthetists and 21 control subjects who matched in age and gender. Chromosome aberrations (CAs) and sister chromatid exchanges (SCEs) assays were performed. All subjects were also genotyped for glutathione S-transferase T1 (GSTT1) gene polymorphisms. Significant differences were found between exposed and controls in terms of SCEs frequency (P = 0.001) and replication index value (P = 0.005), but not in terms of CAs (P = 0.201) and aberrant cells (P = 0.227) frequencies. Regression analyses indicated that age and the years of employment did not influence the level of chromosomal damage in both groups. Finally, among anesthetists, GSTT1 null individuals showed a significant higher frequency of SCE with respect to GSTT1-positive subjects.

Aim Small body size in Madagascar’s dwarf and mouse lemurs (Cheirogalei-dae) is generally viewed as primitive. We investigated the evolution of bodysize in this family and in its sister-taxon, the Lepilemuridae, from phylogenetic,ontogenetic and adaptive perspectives.Location Madagascar.Methods We used a phylogenetic method to reconstruct the evolution ofbody size in lemurs, and allometric regression models of gestation periods andstatic and growth allometries in Cheirogaleidae and Lepilemuridae to test thehypothesis that dwarfing occurred as a result of truncated ontogeny (progene-sis). We also examined adaptive hypotheses relating body size to environmentalvariability, life history, seasonality of reproduction, hypothermy (use of tor-por), and a diet rich in plant exudates.Results Our results indicated that cheirogaleids experienced at least four inde-pendent events of body size reduction from an ancestor as large as livingLepilemuridae, by means of progenesis. Our interpretation is supported by thepaedomorphic appearance and parallel ontogenetic trajectories of the dwarftaxa, as well as their very short gestation periods and increased fecundity.Lepilemur species that occupy more predictable environments are significantlylarger than those occupying unpredictable habitats.Main conclusions Cheirogaleidae appear to be paedomorphic dwarfs, a con-sequence of progenesis, probably as an adaptation to high environmentalunpredictability. Although the capacity to use hypothermy is related to smallbody size, this advantage is unlikely to have driven dwarfing in cheirogaleids.We propose that gummmivory/exudativory co-evolved with body size reduc-tion in this clade, probably from a folivorous ancestor. Their small size isderived, and their suitability as models for the ‘ancestral primate’ is thereforedubious.KeywordsAncestor reconstruction, body size evolution, dwarfism, hypervariability,island rule, lemurs, Lepilemuridae, Madagascar, ontogeny, progenesis.INTRODUCTIONThe currently popular model of a small, nocturnal primateancestor was largely inspired by an extant family of Malagasylemurs, the Cheirogaleidae, which includes the smallest livingprimates (30–400 g). Mouse lemurs (Microcebus spp.), inparticular, are believed to have retained a series of primitivecharacters associated with their very small size (30–100 g):nocturnality, insectivorous/omnivorous diet, fast life history,nest-building, altricial infants carried by mouth, solitarysocial structure, and a promiscuous mating system (Charles-Dominique & Martin, 1970; Cartmill, 1972, 1974, 1992;Martin, 1972, 1990; Kappeler, 1998; Wimmer et al., 2002;Gebo, 2004; Scheumann & Zimmermann, 2008; Montgomeryet al., 2010; but see Soligo, 2006; Masters et al., 2007; Soligo& Martin, 2007). This interpretation is frequently associated

Cannabinoids, the bioactive constituents of Cannabis sativa, and endocannabinoids, among which the most important are anandamide and 2-arachidonoylglycerol, control various biological processes by binding to specific G protein-coupled receptors, namely CB1 and CB2 cannabinoid receptors. While a vast amount of information on the mammalian endocannabinoid system does exist, few data have been reported on bony fish. In the goldfish, Carassius auratus, the CB1 receptor has been cloned and its distribution has been analyzed in the retina, brain and gonads, while CB2 had not yet been isolated. In the present paper we cloned the goldfish CB2 receptor and show that it presents a quite high degree of amino acid identity with zebrafish Danio rerio CB2A and CB2B receptors, while the percentage of identity is lower with the pufferfish Fugu rubripes CB2, as also confirmed by the phylogenetic analysis. The sequence identity becomes much lower when comparing the goldfish and the mammalian CB2 sequences; as for other species, goldfish CB2 and CB1 amino acid sequences share moderate levels of identity. Western-blotting analysis shows the CB2 receptor as two major bands of about 53 kDa and 40 kDa, and other faint bands with apparent molecular masses around 70 kDa, 57 kDa and 55 kDa. Since the distribution of a receptor could give information on its physiological role, we evaluated and compared CB1 and CB2 mRNA expression in different goldfish organs by means of quantitative Real-Time PCR. Our results show that both CB1 and CB2 receptors are widely expressed in the goldfish, displaying some tissue specificities, thus opening the way for further functional studies on bony fish and other non-mammalian vertebrates.

The present work attempts to determine the distribution of GSTM1 and GSTT1 genotype and allele frequencies in a sample of northern Italian population, and to examine the age-related association of these polymorphisms. The frequencies of the deleted GSTM1 and GSTT1 genotypes were 0.357 and 0.169, respectively. GSTT1 null-genotype frequency found in this work further confirms data obtained in previous studies of Italian populations, while for GSTM1 deletion our sample showed a significantly lower-frequency value with respect to other Italian and European populations, with exception of the Greek. No significant differences occurred between men and women in the frequency of each gene, which could suggest that, in the studied sample, there were no sex differences in susceptibility to diseases and in detoxifying enzymes such as GSTs. In order to analyze the relationship between GSTT1 and GSTM1 gene polymorphisms and age, the sample was subdivided into four age groups: 1-30 years (n = 101); 31-50 years (n = 160); 51-79 years (n = 144) and 80-100 years (n = 58). This age-related analysis showed a decreasing gradient of GSTs null genotypes between younger and older groups, with the 80-100 age group showing a significantly lower frequency of GSTT1 null, GSTM1 null and GSTT1/GSTM1 double null genotypes with respect to the younger group.

The phylogeny of the Afro-Asian Lorisoidea is controversial. While postcranial data attest strongly to the monophyly of the Lorisidae, most molecular analyses portray them as paraphyletic and group the Galagidae alternately with the Asian or African lorisids. One of the problems that has bedevilled phylogenetic analysis of the group in the past is the limited number of taxa sampled for both ingroup families. We present the results of a series of phylogenetic analyses based on 635 base pairs (bp) from two mitochondrial genes (12S and 16S rRNA) with and without 36 craniodental characters, for 11 galagid and five lorisid taxa. The outgroup was the gray mouse lemur (Microcebus murinus). Analyses of the molecular data included maximum parsimony (MP), neighbor joining (NJ), maximum likelihood (ML), and Bayesian methods. The model-based analyses and the combined “molecules+morphology” analyses supported monophyly of the Lorisidae and Galagidae. The lorisids form two geographically defined clades. We find no support for the taxonomy of Galagidae as proposed recently by Groves [Primate Taxonomy, Washington, DC: Smithsonian Institution Press. 350 p, 2001]. The taxonomy of Nash et al. [International Journal of Primatology 10:57–80, 1989] is supported by the combined “molecules+morphology” analysis; however, the model-based analyses suggest that Galagoides may be an assemblage of species united by plesiomorphic craniodental characters. Am. J. Primatol. 69:6–15, 2007. © 2006 Wiley-Liss, Inc.

With the aim of further investigating the molecular evolution of beta defensin genes, after having analysed beta defensin 1 (DEFB1) in humans and several nonhuman primate species, we have studied the evolution of the beta defensin 2 gene (DEFB2), which codifies for a peptide with antimicrobial and chemoattractant activity, in humans and 16 primate species. We have found evidence of positive selection during the evolution of orthologous DEFB2 genes at two points on a phylogenetic tree relating these primates: during the divergence of the platyrrhines from the catarrhines and during the divergence of the Cercopithecidae from the Hylobatidae, Great Apes and humans. Furthermore, amino acid variations in Old World Monkeys seem to centre either on residues that are involved in oligomerisation in the human molecule, or that are conserved (40-80%) in beta-defensins in general. It is thus likely that these variations affect the biological function of the molecules and suggest that their synthesis and functional analysis might reveal interesting new information as to their role in innate immunity.

Degenerate PCR primers were used to amplify a conserved gene portion coding chitin synthase from genomic DNA of six species of ectomycorrhizal truffles. DNA was extracted from both hypogeous fruitbodies and in vitro growing mycelium of Tuber borchii. A single fragment of about 600 bp was amplified for each species. The amplification products from Tuber magnatum, T. borchii and T. ferrugineum were cloned and sequenced, revealing a high degree of identity (91.5%) at the nucleotide level. On the basis of the deduced amino acid sequences these clones were assigned to class II chitin synthase. Southern blot experiments performed on genomic DNA showed that the amplification products derive from a single copy gene. Phylogenetic analysis of the nucleotide sequences of class II chitin synthase genes confirmed the current taxonomic position of the genus Tuber, and suggested a close relationship between T. magnatum and T. uncinatum.