Monitoring Great Ape and Elephant Abundance at Large Spatial Scales: Measuring Effectiveness of a Conservation Landscape

Protected areas are fundamental to biodiversity conservation, but there is growing recognition of the need to extend beyond protected areas to meet the ecological requirements of species at larger scales. Landscape-scale conservation requires an evaluation of management impact on biodiversity under different land-use strategies; this is challenging and there exist few empirical studies. In a conservation landscape in northern Republic of Congo we demonstrate the application of a large-scale monitoring program designed to evaluate the impact of conservation interventions on three globally threatened species: western gorillas, chimpanzees and forest elephants, under three land-use types: integral protection, commercial logging, and community-based natural resource management. We applied distance-sampling methods to examine species abundance across different land-use types under varying degrees of management and human disturbance. We found no clear trends in abundance between land-use types. However, units with interventions designed to reduce poaching and protect habitats - irrespective of land-use type - harboured all three species at consistently higher abundance than a neighbouring logging concession undergoing no wildlife management. We applied Generalized-Additive Models to evaluate a priori predictions of species response to different landscape processes. Our results indicate that, given adequate protection from poaching, elephants and gorillas can profit from herbaceous vegetation in recently logged forests and maintain access to ecologically important resources located outside of protected areas. However, proximity to the single integrally protected area in the landscape maintained an overriding positive influence on elephant abundance, and logging roads – even subject to anti-poaching controls - were exploited by elephant poachers and had a major negative influence on elephant distribution. Chimpanzees show a clear preference for unlogged or more mature forests and human disturbance had a negative influence on chimpanzee abundance, in spite of anti-poaching interventions. We caution against the pitfalls of missing and confounded co-variables in model-based estimation approaches and highlight the importance of spatial scale in the response of different species to landscape processes. We stress the importance of a stratified design-based approach to monitoring species status in response to conservation interventions and advocate a holistic framework for landscape-scale monitoring that includes smaller-scale targeted research and punctual assessment of threats.     

The myelin oligodendrocyte glycoprotein directly binds nerve growth factor to modulate central axon circuitry

Myelin oligodendrocyte glycoprotein (MOG) is a central nervous system myelin-specific molecule expressed on the outer lamellae of myelin. To date, the exact function of MOG has remained unknown, with MOG knockout mice displaying normal myelin ultrastructure and no apparent specific phenotype. In this paper, we identify nerve growth factor (NGF) as a binding partner for MOG and demonstrate that this interaction is capable of sequestering NGF from TrkA-expressing neurons to modulate axon growth and survival. Deletion of MOG results in aberrant sprouting of nociceptive neurons in the spinal cord. Binding of NGF to MOG may offer widespread implications into mechanisms that underlie pain pathways.     

Interpretation of tracer data: Some factors which reduce the number of terms in the specific activity functions inn-pool systems

The number of exponential terms in the function which describes the change in the specific activity of a pool following the injection of an isotopically labeled tracer is usually considered to equal the number of pools in which the labeled compound is distributed. However, the number of exponential terms may be smaller than the actual number of pools in the system, even if all pools exchange material with each other. This study is concerned with the derivation of relationships among the fractional rates of transfer between pools which are necessary and sufficient for a reduction in the number of exponential terms for all exchanging pools. The concept of linear dependence among the specific activity functions is basic to this analysis. By considering these relationships, it is possible to interpret the data on the basis of models consisting of a large number of pools which satisfy the condition of fast internal mixing. Such models may be necessary for a meaningful interpretation of tracer data obtained from biological systems.     

Associations between enzyme genotypes and dark respiration in perennial ryegrass,Lolium perenne L.

Summary In this study, we determined whether relationships existed between dark respiration and genotype at five enzyme polymorphisms in perennial ryegrass, Lolium perenne L. Positive correlations were found between Q ₁₀ of dark respiration and genotype at the phosphoglucomutase (PGM) and 6-phosphogluconate dehydrogenase (6PGD) loci. Plants doubly homozygous for the common allele at these loci were found to have Q ₁₀ values 20% higher than those for double heterozygotes. In plants that were heat stressed for five consecutive days, Q ₁₀ was found to be negatively correlated with apparent vigor after stressing. Individuals homozygous for PGM and 6PGD (with higher Q ₁₀ values) exhibited more apparent damage following the stress than heterozygous individuals. Both PGM and 6PGD occupy positions in metabolism with regulatory potential. Although caution must be used in assigning causal relationships, the results suggest that specific forms of these enzymes are directly related to, or are correlated with, the determinants of respiratory efficiency in L. perenne.     

Genetic variation of Batrachochytrium dendrobatidis is linked to skin bacterial diversity in the Pacific treefrog Hyliola regilla (hypochondriaca)

Symbiotic bacterial communities are crucial to combating infections and contribute to host health. The amphibian skin microbiome plays an important role in protecting their hosts against pathogens such as Batrachochytrium dendrobatidis (Bd), one of the causative agents of chytridiomycosis, which is responsible for dramatic amphibian population declines worldwide. Although symbiotic skin bacteria are known to inhibit Bd growth, an understanding of the relationship between Bd genetic variability, environmental conditions, and skin bacterial communities is limited. Therefore, we examined the associations between Bd infection load, Bd genetic diversity and skin bacterial communities in five populations of Hyliola regilla (hypochondriaca) from environmentally contrasting sites in Baja California, Mexico. We observed differences in Bd genetics and infection load among sites and environments. Genetic analysis of Bd isolates revealed patterns of spatial structure corresponding to the five sites sampled. Amphibian skin bacterial diversity and community structure differed among environments and sites. Bacterial community composition was correlated with Bd genetic differences and infection load, with specific bacterial taxa enriched on infected and un-infected frogs. Our results indicate that skin-associated bacteria and Bd strains likely interact on the host skin, with consequences for microbial community structure and Bd infection intensity.     

Genome sequence of the biocontrol strain Pseudomonas fluorescens F113

Pseudomonas fluorescens F113 is a plant growth-promoting rhizobacterium (PGPR) that has biocontrol activity against fungal plant pathogens and is a model for rhizosphere colonization. Here, we present its complete genome sequence, which shows that besides a core genome very similar to those of other strains sequenced within this species, F113 possesses a wide array of genes encoding specialized functions for thriving in the rhizosphere and interacting with eukaryotic organisms.     

Oceanicella actignis gen. nov., sp. nov., a halophilic slightly thermophilic member of the Alphaproteobacteria

Two isolates, designated PRQ-67^T and PRQ-68, with an optimum growth temperature of about 50 °C, growth range in medium containing between 1 and 9% NaCl and an optimum pH for growth between 7.5 and 8.0, were recovered from a shallow marine hot spring on a beach, Praia do Fogo, at Ribeira Quente, on the Island of São Miguel in the Azores. Comparisons of 16S rRNA gene sequences show these strains to be most closely related (93.1–94.7% similarity) to species of the genus Amaricoccus, within the family Rhodobacteraceae. Strains are non-pigmented and form non-motile pleomorphic cells that stain Gram-negative, are aerobic, oxidase and catalase positive. The major fatty acids are C_18:1ω7c and C_18:1ω7c 11-methyl. Ubiquinone 10 is the major respiratory quinone. Major polar lipids are phosphatidylcholine, phosphatidylglycerol and one aminolipid. Based on 16S rRNA gene sequence analysis, physiological and biochemical characteristics we describe a new species of a novel genus represented by strain PRQ-67^T (=DSM 22673^T = LMG 25334^T) for which we propose the name Oceanicella actignis.     

A new function in translocation for the mitochondrial i-AAA protease Yme1: import of polynucleotide phosphorylase into the intermembrane space

Polynucleotide phosphorylase (PNPase) is an exoribonuclease and poly(A) polymerase postulated to function in the cytosol and mitochondrial matrix. Prior overexpression studies resulted in PNPase localization to both the cytosol and mitochondria, concurrent with cytosolic RNA degradation and pleiotropic cellular effects, including growth inhibition and apoptosis, that may not reflect a physiologic role for endogenous PNPase. We therefore conducted a mechanistic study of PNPase biogenesis in the mitochondrion. Interestingly, PNPase is localized to the intermembrane space by a novel import pathway. PNPase has a typical N-terminal targeting sequence that is cleaved by the matrix processing peptidase when PNPase engaged the TIM23 translocon at the inner membrane. The i-AAA protease Yme1 mediated translocation of PNPase into the intermembrane space but did not degrade PNPase. In a yeast strain deleted for Yme1 and expressing PNPase, nonimported PNPase accumulated in the cytosol, confirming an in vivo role for Yme1 in PNPase maturation. PNPase localization to the mitochondrial intermembrane space suggests a unique role distinct from its highly conserved function in RNA processing in chloroplasts and bacteria. Furthermore, Yme1 has a new function in protein translocation, indicating that the intermembrane space harbors diverse pathways for protein translocation.