A genetic linkage map of the vervet monkey (Chlorocebus aethiops sabaeus)

The spectacular progress in genomics increasingly highlights the importance of comparative biology in biomedical research. In particular, nonhuman primates, as model systems, provide a crucial intermediate between humans and mice. The close similarities between humans and other primates are stimulating primate studies in virtually every area of biomedical research, including development, anatomy, physiology, immunology, and behavior. The vervet monkey (Chlorocebus aethiops sabaeus) is an important model for studying human diseases and complex traits, especially behavior. We have developed a vervet genetic linkage map to enable mapping complex traits in this model organism and facilitate comparative genomic analysis between vervet and other primates. Here we report construction of an initial genetic map built with about 360 human orthologous short tandem repeats (STRs) that were genotyped in 434 members of an extended vervet pedigree. The map includes 226 markers mapped in a unique order with a resolution of 9.8 Kosambi centimorgans (cM) in the vervet monkey genome, and with a total length (including all 360 markers) of 2726 cM. At least one complex and 11 simple rearrangements in marker order distinguish vervet chromosomes from human homologs. While inversions and insertions can explain a similar number of changes in marker order between vervet and rhesus homologs, mostly inversions are observed when vervet chromosome organization is compared to that in human and chimpanzee. Our results support the notion that large inversions played a less prominent role in the evolution within the group of the Old World monkeys compared to the human and chimpanzee lineages. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.     

Interactions of Bacterial and Amoebal Populations in Soil Microcosms with Fluctuating Moisture Content

Sterilized soil samples (20 g of soil per 50-ml flask), amended with 600 μg of glucose-carbon and 60 μg of NH₄-N · g of dry soil⁻¹, were inoculated with bacteria (Pseudomonas paucimobilis) alone or with bacteria and amoebae (Acanthamoeba polyphaga). We used wet-dry treatments, which involved air drying the samples to a moisture content of approximately 2% and remoistening the samples three times during the 83-day experiment. Control treatments were kept moist. In the absence of amoebae, bacterial populations were reduced by the first drying to about 60% of the moist control populations, but the third drying had no such effect. With amoebae present, bacterial numbers were not significantly affected by the dryings. Amoebal grazing reduced bacterial populations to 20 to 25% of the ungrazed bacterial populations in both moisture treatments. Encystment was an efficient survival mechanism for amoebae subjected to wet-dry cycles. The amoebal population was entirely encysted in dry soil, but the total number of amoebae was not affected by the three dryings. Growth efficiencies for amoebae feeding on bacteria were 0.33 and 0.39 for wet-dry and constantly moist treatments, respectively, results that compared well with those previously reported for Acanthamoeba spp.     

Hypoxanthine-Guanine Phosphoribosyltransferase Deficiency: Biochemical and Molecular Findings in Six Argentine Patients

Hypoxanthine-guanine phosphoribosyltransferase (HPRT) deficiency is an inborn error of purine metabolism responsible for Lesch-Nyhan Disease (LND) and its partial phenotypes, HPRT-related hyperuricemia with neurologic dysfunction (HRND) and hyperuricemia alone. We report here the recognition of six Argentine patients, two with LND and four with HRND. All patients presented elevated excretion of uric acid, hypoxanthine, and xanthine and decreased HPRT enzyme activities <1 nmol/h/mg Hb. The molecular analysis demonstrated in the two LND patients a novel inherited transition mutation, c.203T >C (L68P), in one subject and a germline transition mutation, c.209G >A (G70E), in the other. In the HRND patients a novel transversion mutation, c.584 A >C (Y195S), was found in three related patients and an inherited transition mutation, c.143G >A (R48H), in the fourth subject.     

HPRT Deficiency: Identification of Twenty-Four Novel Variants Including an Unusual Deep Intronic Mutation

Hypoxanthine phosphoribosyltranferase (HPRT) deficiency is an X-linked disorder of purine salvage that ranges phenotypically from hyperuricaemia to Lesch–Nyhan Syndrome. Molecular testing is necessary to identify female carriers within families as a prelude to prenatal diagnosis. During the period 1999–2010 the Purine Research Laboratory studied 106 patients from 68 different families. Genomic sequencing revealed mutations in 88% of these families, 24 of which were novel. In eight patients, exon sequencing was not informative. Copy-DNA analysis in one patient revealed an insertion derived from a deep intronic sequence with a genomic mutation flanking this region, resulting in the creation of a false exon. Carrier testing was performed in 21 mothers of affected patients, out of these, 81% (17) were found to be carriers of the disease-associated mutation. Our results confirm the extraordinary variety and complexity of mutations in HPRT deficiency. A combination of genomic and cDNA sequencing may be necessary to define mutations.     

The Impact of Health Status on Dispersal Behavior in Banded Mongooses (Mungos mungo)

While disease and injury have obvious impacts on mortality, they can have less understood non-lethal impacts on behavior. These behavioral effects might have a significant consequences for population-level disease dynamics if diseased individuals are more or less likely to disperse. We opportunistically observed dispersal events in banded mongooses (Mungos mungo) that were either healthy or unhealthy due to injury and/or clinical signs of a novel tuberculosis pathogen, Mycobacterium mungi. We found that diseased and/or injured mongooses were significantly less likely to disperse than healthy individuals, suggesting that disease may have an important consequences for dispersal that could in turn affect population-level disease dynamics.     

Inheritance of large mitochondrial RNA's in alfalfa

Summary Several large RNA molecules that migrated to electrophoretic positions ranging from 1.7–10 kb were observed in preparation of alfalfa (Medicago sativa) mitochondria. F₁ progenies inherited the RNA's from both maternal and paternal parents (Fig. 1). Treatment of intact mitochondria with RNase A failed to remove the RNA's, indicating that they were contained within an RNase impermeable compartment. Further purification of mitochondria in linear sucrose gradients failed to separate the RNA's from mitochondria. Transmission electron microscopic examination of sucrose gradient purified mitochondria revealed that mitochondria were free of contamination by virus-like particles, indicating that the RNA's were contained within the mitochondrion. Biparental inheritance of large mitochondrial RNA's in alfalfa provides evidence that mitochondria are inherited biparentally in this species.     

Relationship of major phosphorylation reactions and MgATPase activities to ATP-dependent shape change of human erythrocyte membranes

Human erythrocyte ghosts prepared by hemolysis and washing in hypotonic Tris are crenated by salt and divalent cations, but undergo shape change to smooth biconcave discs and stomatocytic forms when incubated with MgATP at 37 degrees C. This is normally accompanied by protein and lipid phosphorylations in which the major phosphate acceptors are the spectrin beta-chain and inositol phospholipids, respectively. The system was manipulated in several ways to demonstrate the independence of ATP-dependent shape change from the major phosphorylation reactions. Salt-extracted membranes incubated with adenosine, an inhibitor of spectrin and phosphatidylinositol kinases, underwent normal shape change despite reductions of greater than 90% in spectrin and phospholipid labeling by [gamma-32P]ATP. ATP-dependent shape change was blocked by vanadate at micromolar concentrations (half-maximal inhibition at less than 1 microM), but vanadate did not inhibit membrane autophosphorylation reactions or turnover of spectrin- or lipid-bound phosphate. Vanadate inhibited part of the ATP hydrolysis that accompanies shape change and is expressed in the presence of ouabain and EGTA. The vanadate-sensitive MgATPase activity was approximately 3 nmol Pi X min-1 X mg of protein-1. The results implicate it in ATP-dependent shape change.     

Fetal and maternal factors associated with infant mortality in vervet monkeys

Background Causes of infant death remain unknown in significant proportions of human and non‐human primate pregnancies. Methods A closed breeding colony with high rates of infant mortality had pregnancies assessed (n = 153) by fetal measurements and maternal characteristics. Infant outcome was classified as neonatal death (stillborn or died <48 hours from birth), postnatal death (died 2–30 days) or surviving (alive after 30 days). Results Fetal size did not predict outcome. Poor maternal glycemic control and low social ranking increased odds for adverse outcome (OR = 3.72, P = 0.01 and 2.27, P = 0.04, respectively). Male sex was over‐represented in stillbirths (P = 0.04), and many were macrosomic, but size did not associate with maternal glycemic control measured as glycated hemoglobin A1c. Postnatally dead infants were smaller (P < 0.01), which associated with behavioral factors and glycemic control. Conclusions Fetal growth estimates predicted gestational age but not fetal outcome. Maternal social status and metabolic health, particularly glycemic control, increased risks of adverse pregnancy outcome.