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The 23 human ZDHHCS-acyltransferases catalyze long-chainS-acylation at cysteine residues across an extensive network of hundreds of proteins important for normal physiology or dysregulated in disease. Here we present a technology platform to directly map the protein substrates of a specific ZDHHC for the first time at the whole proteome level, in intact cells. Structure-guided engineering of paired ZDHHC ‘hole’ mutants and ‘bumped’ chemically tagged fatty acid probes enabled probe transfer to specific protein substrates with excellent selectivity over wild type ZDHHCs. Chemical genetic systems were exemplified for five ZDHHCs (3, 7, 11, 15 and 20), and applied to generate the firstde novoZDHHC substrate profiles, identifying >300 unique and shared substrates across multiple cell lines andS-acylation sites for novel functionally diverse substrates. We expect that this powerful and versatile platform will open a new window onS-acylation biology for a wide range of models and organisms.

Conjugated polymers are organic semiconductors that can be used for fluorescence microscopy of living specimens. Here, we report the encapsulation of the bright-red-emitting conjugated polymer, poly[{9,9-dihexyl-2,7-bis(1-cyanovinylene)fluorenylene}-alt-co-{2,5-bis(N,N′-diphenylamino)-1,4-phenylene}] (CN-FO-DPD), and superparamagnetic iron oxide nanoparticles (SPIONs) within poly(styrene-co-maleic anhydride) (PSMA) micelles. The resulting particles exhibited an emission peak at 657 nm, a fluorescence quantum yield of 21%, an average diameter of 65 nm, and a ζ potential of -30 mV. They are taken up by cells, and we describe their use in fluorescence microscopy of living Hela cells and zebrafish embryos and their associated cytotoxicity in HEK, HeLa, and HCE cells.

Lipids are key constituents of all cells, which express thousands of different lipid species. In most cases, it is not known why cells synthesize such diverse lipidomes, nor what regulates their metabolism. Although it is known that dividing cells specifically regulate their lipid content and that the correct lipid complement is required for successful division, it is unclear how lipids connect with the cell division machinery. Here, we report that the membrane protein stomatin is involved in the cytokinesis step of cell division. Although it is not a lipid biosynthetic enzyme, depletion of stomatin causes cells to change their lipidomes. These changes include specific lipid species, like ether lipids, and lipid families like phosphatidylcholines. Addition of exogenous phosphatidylcholines rescues stomatin-induced defects. These data suggest that stomatin interfaces with lipid metabolism. Stomatin has multiple contacts with the plasma membrane and we identify which sites are required for its role in cell division, as well as associated lipid shifts. We also show that stomatin's mobility on the plasma membrane changes during division, further supporting the requirement for a highly regulated physical interaction between membrane lipids and this newly identified cell division protein.

The amyloid precursor protein (APP), a key player in Alzheime’s disease (AD), is part of a larger gene family, including the APP like proteins APLP1 and APLP2. They share similar structures, form homo- and heterotypic dimers and exhibit overlapping functions. We investigated complex formation of the APP family members via two inducible dimerization systems, the FKBP-rapamycin based dimerization as well as cysteine induced dimerization, combined with coimmunoprecipitations and Blue Native (BN) gel analyses. Within the APP family, APLP1 shows the highest degree of dimerization and high molecular weight (HMW) complex formation. Interestingly, about 20% of APP is dimerized in cultured cells while about 50% of APP is dimerized in mouse brains, independent of age and splice forms. Furthermore, we could show that dimerized APP originates mostly from neurons and is enriched in synaptosomes. Finally, BN gel analysis of human cortex samples shows a significant decrease of APP dimers in AD patients compared to controls, suggesting that loss of dimers of full-length APP might correlate with loss of synapses in the process of AD.

A requirement for PKCε in exiting from the Aurora B dependent abscission checkpoint is associated with events at the midbody, however, the recruitment, retention and action of PKCε in this compartment are poorly understood. Here, the prerequisite for 14-3-3 complex assembly in this pathway is directly linked to the phosphorylation of Aurora B S227 at the midbody. However, while essential for PKCε control of Aurora B, 14-3-3 association is shown to be unnecessary for the activity-dependent enrichment of PKCε at the midbody. This localisation is demonstrated to be an autonomous property of the inactive PKCε D532N mutant, consistent with activity-dependent dissociation. The C1A and C1B domains are necessary for this localisation, while the C2 domain and inter-C1 domain (IC1D) are necessary for retention at the midbody. Furthermore, it is shown that while the IC1D mutant retains 14-3-3 complex proficiency, it does not support Aurora B phosphorylation, nor rescues division failure observed with knockdown of endogenous PKCε. It is concluded that the concerted action of multiple independent events facilitates PKCε phosphorylation of Aurora B at the midbody to control exit from the abscission checkpoint.

Equipping DNA with hydrophobic anchors enables targeted interaction with lipid bilayers for applications in biophysics, cell biology, and synthetic biology. Understanding DNA–membrane interactions is crucial for rationally designing functional DNA. Here we study the interactions of hydrophobically tagged DNA with synthetic and cell membranes using a combination of experiments and atomistic molecular dynamics (MD) simulations. The DNA duplexes are rendered hydrophobic by conjugation to a terminal cholesterol anchor or by chemical synthesis of a charge-neutralized alkyl-phosphorothioate (PPT) belt. Cholesterol-DNA tethers to lipid vesicles of different lipid compositions and charges, while PPT DNA binding strongly depends on alkyl length, belt position, and headgroup charge. Divalent cations in the buffer can also influence binding. Our MD simulations directly reveal the complex structure and energetics of PPT DNA within a lipid membrane, demonstrating that longer alkyl-PPT chains provide the most stable membrane anchoring but may disrupt DNA base paring in solution. When tested on cells, cholesterol-DNA is homogeneously distributed on the cell surface, while alkyl-PPT DNA accumulates in clustered structures on the plasma membrane. DNA tethered to the outside of the cell membrane is distinguished from DNA spanning the membrane by nuclease and sphingomyelinase digestion assays. The gained fundamental insight on DNA–bilayer interactions will guide the rational design of membrane-targeting nanostructures.

Organisms use color for camouflage, sexual signaling, or as a warning sign of danger. Primates are one of the most vibrantly colored Orders of mammals. However, the genetics underlying their coat color are poorly known, limiting our ability to study molecular aspects of its evolution. The role of the melanocortin 1 receptor (MC1R) in color evolution has been implicated in studies on rocket pocket mice (Chaetodipus intermediusi), toucans (Ramphastidae), and many domesticated animals. From these studies, we know that changes in MC1R result in a yellow/red or a brown/black morphology. Here, we investigate the evolution of MC1R in Lorisidae, a monophyletic nocturnal primate family, with some genera displaying high contrast variation in color patterns and other genera being monochromatic. Even more unique, the Lorisidae family has the only venomous primate: the slow loris (Nycticebus). Research has suggested that the contrasting coat patterns of slow lorises are aposematic signals for their venom. If so, we predict the MC1R in slow lorises will be under positive selection. In our study, we found that Lorisidae MC1R is under purifying selection (ω = 0.0912). In Lorisidae MC1R, there were a total of 75 variable nucleotides, 18 of which were nonsynonymous. Six of these nonsynonymous substitutions were found on the Perodicticus branch, which our reconstructions found to be the only member of Lorisidae that has predominantly lighter coat color; no substitutions were associated with Nycticebus. Our findings generate new insight into the genetics of pelage color and evolution among a unique group of nocturnal mammals and suggest putative underpinnings of monochromatic color evolution in the Perodicticus lineage., In primates, the most colorful of mammals, few have examined the influence the melanocortin 1 receptor (MC1R) has on color variation (light or dark) in primates. Here, we examined how MC1R impacts color variation in a cryptic primate family with high contrasting color variation. We found MC1R is under purifying selection, but there appears to be a link in nucleotide changes and light coat color.

Significance Cells generate a vast repertoire of lipid molecules whose functions are poorly understood. To investigate whether lipids can regulate cell fate decisions, we carried out a systematic lipidomic analysis and perturbation of lipid metabolism in cultured human epidermal keratinocytes, determining associations with the onset of differentiation. We identified individual lipid species that induced exit from the epidermal stem cell compartment. Our observations suggest that more research is warranted on the regulation of biological processes via lipid species, moving beyond the more conventional contribution of proteins and nucleic acids., While the lipids of the outer layers of mammalian epidermis and their contribution to barrier formation have been extensively described, the role of individual lipid species in the onset of keratinocyte differentiation remains unknown. A lipidomic analysis of primary human keratinocytes revealed accumulation of numerous lipid species during suspension-induced differentiation. A small interfering RNA screen of 258 lipid-modifying enzymes identified two genes that on knockdown induced epidermal differentiation: ELOVL1, encoding elongation of very long-chain fatty acids protein 1, and SLC27A1, encoding fatty acid transport protein 1. By intersecting lipidomic datasets from suspension-induced differentiation and knockdown keratinocytes, we pinpointed candidate bioactive lipid subspecies as differentiation regulators. Several of these—ceramides and glucosylceramides—induced differentiation when added to primary keratinocytes in culture. Our results reveal the potential of lipid subspecies to regulate exit from the epidermal stem cell compartment.

Due to geologic processes and recent anthropogenic introductions, patterns of genetic and morphological diversity within the Smallmouth Bass (Micropterus dolomieu), which are endemic to the central and eastern United States (USA), are poorly understood. We assessed genetic and morphological differentiation between the widespread Northern Smallmouth Bass (M. d. dolomieu) and the more restricted Neosho Smallmouth Bass (M. d. velox) where their ranges meet in the Central Interior Highlands ecoregion (CIH). Data from 14 microsatellite loci were used to conduct Structure and principal components analyses to evaluate diversity across populations and screen for hybridization with sympatric Spotted Bass (M. punctulatus). We also tested for morphological differences using five morphometric traits and one meristic trait. We found support for three genetic clusters corresponding to previously described taxonomic variation; five clusters largely corresponding to river systems; and nine clusters representing hierarchical population structure within both ranges. We found evidence of a unique genetic cluster in tributaries of the White River within the Northern Smallmouth Bass range and admixture between the subspecies throughout the Neosho range. We also found evidence of morphological differentiation between subspecies; Neosho Smallmouth Bass exhibited larger head length than Northern Smallmouth Bass relative to total length, and there was a significant interaction of subspecies and orbital length, possibly indicating differential growth patterns between subspecies. Our results reveal multiple levels of divergence, suggesting the CIH harbors greater and more complex Smallmouth Bass diversity than previously thought.

During division, eukaryotic cells undergo a dramatic, complex and coordinated remodelling of their cytoskeleton and membranes. For cell division to occur, chromosomes must be segregated and new cellular structures, such as the spindle apparatus, must be assembled. Pre-existing organelles, such as the nuclear envelope, endoplasmic reticulum and Golgi apparatus, must be disassembled or remodelled, distributed and reformed. Smaller organelles such as mitochondria as well as cytoplasmic content must also be properly distributed between daughter cells. This mixture of organelles and cytoplasm is bound by a plasma membrane that is itself subject to remodelling as division progresses. The lipids resident in these different membrane compartments play important roles in facilitating the division process. In recent years, we have begun to understand how membrane remodelling is coordinated during division; however, there is still much to learn. In this Review, we discuss recent insights into how these important cellular events are performed and regulated. During cell division, the distribution of membrane-bound organelles needs to be tightly regulated to ensure the proper composition and function of daughter cells. Recent studies have shed light on the range of complex and dynamic mechanisms needed to mediate organelle inheritance and membrane remodelling during cell division.

Population restoration is an inherently costly conservation practice typically reliant on animal translocations. There are many approaches to translocation and consideration is paid to understanding how various translocation models influence restoration success. Translocation strategies are often designed to meet site‐specific objectives, minimize cost, and maximize success. We investigated genetic diversity retention associated with the low‐founder, multi‐release, single admixed stock translocation model of the Missouri elk (Cervus canadensis) restoration in 2011–2013. We further estimated effective population size and projected future losses in genetic diversity if the restored Missouri elk herd is maintained at the population size objective with no immigration from neighboring states. We observed relatively high levels of genetic diversity retention as evidenced by minimal losses in allelic richness and expected heterozygosity. Our projections indicated 90% genetic diversity retention within the Missouri population for roughly 130 years. Where number of progeny or source stocks are limited by resource or disease considerations, use of a relatively low‐founder, single admixed source may enable retention of genetic variation, while minimizing costs.

Despite containing the largest extent of unfragmented landscape in the Asian elephant (Elephas maximus) range, Myanmar has high levels of human–elephant conflict. The Bago Yoma mountain region of central Myanmar has previously been identified as an elephant conflict hotspot, characterized by high levels of crop-raiding and illegal killing of elephants for the ivory and skin trades. We used non-invasive fecal sampling to evaluate the population structure and demography of wild and captive elephants in the Bago Yoma using microsatellite loci and mitochondrial DNA in combination with crop-raiding status, age, and sex. We were able to collect 252 samples from wild elephants –119 directly following conflict events– and 25 from captive elephants from which we identified 127 unique wild and 21 captive individuals. The population was biased toward subadults, which could be an important contributor to the high rates of conflict, as these individuals may lack the experience to avoid dangerous behaviors. Conflict elephants were primarily male, although both sexes and all ages engaged in crop-raiding, including females with juveniles. We found that elephants that commit solo raids were all male, while larger raiding parties often included both related and unrelated individuals of both sexes. Repeat offenders were common. These wild elephants contained high levels of genetic diversity, differentiated from local captive populations, and valuable for the species’ conservation. Overall, the elephants of Bago Yoma, Myanmar have been heavily affected by conflict, and managers could utilize the knowledge presented to aid in the preservation of this population.

Aim For many endemic species with limited dispersal capacities, the relationship between landscape changes and species distributions is still unclear. We characterized the population structure of the endemic ringed salamander (Ambystoma annulatum) across its distribution in the Central Interior Highlands (CIH) of North America, an area of high species endemism, to infer the ecological and evolutionary history of the species. Methods We sampled 498 individuals across the species distribution and characterized the population genetic structure using nuclear microsatellite and mitochondrial DNA (mtDNA) markers. Results Ambystoma annulatum exist in two strongly supported nuclear genetic clusters across the CIH that correspond to a northern cluster that includes the Missouri Ozark populations and a southern cluster that includes the Arkansas and Oklahoma Ozarks and the Ouachita Mountains. Our demographic models estimated that these populations diverged approximately 2,700 years ago. Pairwise estimates of genetic differentiation at microsatellite and mtDNA markers indicated limited contemporary gene flow and suggest that genetic differentiation was primarily influenced by changes in the post‐Pleistocene landscape of the CIH. Main Conclusions Both the geologic history and post‐European settlement history of the CIH have influenced the population genetic structure of A. annulatum. The low mtDNA diversity suggests a retraction into and expansion out of refugial areas in the south‐central Ozarks, during temperature fluctuations of the Pleistocene and Holocene epochs. Similarly, the estimated divergence time for the two nuclear clusters corresponds to changes in the post‐Pleistocene landscape. More recently, decreased A. annulatum gene flow may be a result of increased habitat fragmentation and alteration post‐European settlement., We characterized the population structure of the endemic ringed salamander (Ambystoma annulatum) across its distribution in the Central Interior Highlands of North America, an area of high species endemism, to infer the ecological and evolutionary history of the species. Both the geologic history and post‐European settlement history of the CIH have influenced the population genetic structure of A. annulatum.

Recent carnivore distributions in eastern Pakistan are poorly documented. In an effort to fill knowledge gaps, we combined field and laboratory molecular approaches to identify the large- and mid-sized mammalian carnivores in Murree, Kotli Sattian, and Kahuta National Park in Rawalpindi, Punjab. A total of 23 sites, each with a transect of 1–4 km in length, were identified and visited monthly over 24 months in 2016–2018. Fecal samples (n = 317) were collected and identified to species in the field based on morphology, odor, and additional signs. A subset (n = 150) of these samples was genetically identified to species using primers designed to amplify an informative region of the canid, felid, mustelid, and viverrid mitochondrial control region. Identified carnivore species for the park include leopard, leopard cat, jungle cat, red fox, golden jackal, small Indian civet, and Canis spp. For leopard, red fox, and golden jackal, field identification rates were accurate at a true-positive rate ≥ 63%. However, there was a notably high rate of field misidentification of putative jungle cat and yellow-throated marten samples, most of which were genetically identified as leopard cat or non-Carnivora samples. We mapped fecal sample presence points based on both morphological and genetically confirmed samples. For five of six dyadic combinations of pairwise species segregation patterns, there was evidence of high rates of non-random co-occurrence of red fox and jackal (p ≤ 0.05). For the other five pairwise combinations, no statistical support was found for non-random distribution. Such findings reiterate the need to combine field and molecular approaches when using fecal samples to survey communities, and underscore the need for broader studies of the carnivore communities of Pakistan.

IntroductionPatients with schizophrenia have a reduced life expectancy compared to the general population, and cardiovascular diseases contribute to this. Peripheral arterial disease (PAD) is associated with excess all-cause mortality and specifically with cardiovascular morbidity and mortality. The risk factors for PAD, such as diabetes, smoking, hypertension, dyslipidaemia and obesity, are more common among patients with schizophrenia which could contribute to a possibly higher prevalence of PAD among patients with schizophrenia.ObjectivesTo investigate PAD utilizing toe brachial index (TBI) in a population of patients diagnosed with schizophrenia with the purpose of establishing prevalence rates amongst newly diagnosed as well as more chronic patients.MethodsA cross-sectional study of patients with schizophrenia (ICD10-diagnosis F20 or F25) with a study population of 57 patients diagnosed with schizophrenia within the last 2 years, psychiatric healthy controls matched by age, sex and smoking status and 142 patients with a schizophrenia diagnosis more than 10 years ago. The primary outcome is TBI in patients with schizophrenia stratified to the two subpopulations. The TBI will be calculated from the arm and toe systolic pressures. The toe pressures were measured using photoplethysmography (SysToe®, Atys Medical).ResultsNo results are available yet. The cohort will be described by age, sex, smoking status, body fat percentage and physical comorbidities. The TBI of the two subpopulations will be compared with psychiatrically healthy controls using paired t-tests if data is normally distributed. If transformation is unsuitable, Wilcoxon test will be carried out instead.ConclusionsNo results are available yet. Results will be presented at the EPA’s congress 2021.DisclosureNo significant relationships.

IntroductionPatients with schizophrenia have a four-fold increased all-cause and a doubled cardiovascular mortality rate as compared to the general population.ObjectivesThe study overall investigates the point-prevalence and prospective changes in cardiovascular risk factors in patients with schizophrenia, with baseline demographics of participants presented here.MethodsA prospective study of patients diagnosed with schizophrenia divided into two subpopulations consisting of newly diagnosed (≤2 years from baseline in study (group A)) or chronic (diagnosed ≥10 years from baseline in study (group B)).ResultsA total of 199 patients (57 diagnosed ≤2 years preceding baseline and 142 diagnosed ≥10 years ago) were included. Group A had been diagnosed for an average of 1.13±0.58 years and 21.19±7.62 years in group B. The majority (n=135 (67.8%)) were diagnosed with paranoid schizophrenia. At baseline PANSS total (median[Q1;Q3]) for group A was 61.0[51.0;76.0] and 60.0[48.0;76.0] for group B, with PANNS Positive being 17.0[13.0;20.0] and 15.0[12;19], PANSS Negative being 16.0[11.0;20.0] and 14.5[10.0;20.0], and PANSS General being 28.0[22.0;35.0] and30.0 [25.0;37.0], respectively. No difference in Clinical Global Impression was observed between groups ((median[Q1;Q3): 4.0[3.0;4.0] in both groups). Lastly, global assessment of function was similar between groups ((median[Q1;Q3): group A symptom: 38.5[37.0;46.0] and group B 41.0[37.0;52.0], and with function being 48.0[44.5;53.5] in group A and 45.5[41.0;53.0] in group B).ConclusionsProspective studies investigating prevalence of and prospective changes in cardiovascular risk in patients with schizophrenia are essential to understand the increased all-cause and cardiovascular specific mortality. Demographic descriptions of participants are essential to estimate generalizability in different treatment settings.DisclosureNo significant relationships.

Wildlife translocations, which involve the introduction of naive hosts into new environments with novel pathogens, invariably pose an increased risk of disease. The meningeal worm Parelaphostrongylus tenuis is a nematode parasite of the white-tailed deer (Odocoileus virginianus), which serves as its primary host and rarely suffers adverse effects from infection. Attempts to restore elk (Cervus canadensis) to the eastern US have been hampered by disease caused by this parasite. Using DNA sequence data from mitochondrial and nuclear genes, we examined the hypothesis that elk translocated within the eastern US could be exposed to novel genetic variants of P. tenuis by detailing the genetic structure among P. tenuis taken from white-tailed deer and elk at a source (Kentucky) and a release site (Missouri). We found high levels of diversity at both mitochondrial and nuclear DNA in Missouri and Kentucky and a high level of differentiation between states. Our results highlight the importance of considering the potential for increased disease risk from exposure to novel strains of parasites in the decision-making process of a reintroduction or restoration.

Rationale: Oral treprostinil improves exercise capacity in patients with pulmonary arterial hypertension (PAH), but the effect on clinical outcomes was unknown.\ud \ud Objectives: To evaluate the effect of oral treprostinil compared with placebo on time to first adjudicated clinical worsening event in participants with PAH who recently began approved oral monotherapy.\ud \ud Methods: In this event-driven, double-blind study, we randomly allocated 690 participants (1:1 ratio) with PAH to receive placebo or oral treprostinil extended-release tablets three times daily. Eligible participants were using approved oral monotherapy for over 30 days before randomization and had a 6-minute-walk distance 150 m or greater. The primary endpoint was the time to first adjudicated clinical worsening event: death; hospitalization due to worsening PAH; initiation of inhaled or parenteral prostacyclin therapy; disease progression; or unsatisfactory long-term clinical response.\ud \ud Measurements and Main Results: Clinical worsening occurred in 26% of the oral treprostinil group compared with 36% of placebo participants (hazard ratio, 0.74; 95% confidence interval, 0.56–0.97; P = 0.028). Key measures of disease status, including functional class, Borg dyspnea score, and N-terminal pro–brain natriuretic peptide, all favored oral treprostinil treatment at Week 24 and beyond. A noninvasive risk stratification analysis demonstrated that oral treprostinil–assigned participants had a substantially higher mortality risk at baseline but achieved a lower risk profile from Study Weeks 12–60. The most common adverse events in the oral treprostinil group were headache, diarrhea, flushing, nausea, and vomiting.\ud \ud Conclusions: In participants with PAH, addition of oral treprostinil to approved oral monotherapy reduced the risk of clinical worsening.\ud \ud Clinical trial registered with www.clinicaltrials.gov (NCT01560624).

By the early 1900s, black bears were believed to be almost extinct in Missouri and Arkansas, presumably due to extensive logging and overharvest. To reestablish Arkansas populations, the Arkansas Game and Fish Commission conducted a translocation program from 1958 to 1968, moving 254 bears from Minnesota and Manitoba, Canada, to the Ozark and Ouachita National Forests. This remains one of the most successful large mammal translocations ever conducted, and the Arkansas population grew rapidly into the thousands. However, bear sightings and nuisance reports suggested that 50 years after the translocations, populations in Missouri were small, and densities were low. We conducted a spatially explicit genetic capture-recapture study to estimate the size and density of the black bear population in south-central Missouri. We genotyped hair samples collected over two years using 15 microsatellite loci and estimated the population size at 279 ± 54 (SE) and the density at 1.7 bears/km2. To infer the source of bears colonizing Missouri, we analyzed the resulting genotypes in the Bayesian clustering program STRUCTURE along with genotypes from Arkansas, Oklahoma, and source populations. The results revealed unique genetic clusters in the Ouachitas, the Ozarks, and the source populations and found that Missouri bears were divided between those that clustered with the Ozarks and a unique cluster. The presence of the unique cluster in Missouri supports the hypothesis that black bears in the Missouri Ozarks were not extirpated but were reduced to very low densities during European settlement and have subsequently become admixed with bears that trace their ancestry to the reintroduction. While some might suggest that the unique Missouri population should be designated as a separate management unit, we caution that this might not be beneficial to the preservation of the Missouri bear population as we have no evidence that it is ecologically or geographically distinct, it has low genetic diversity, and the genetic differentiation may not be related to adaptive differences.

Elephants, which are among the most high-profile of the charismatic megafauna, are increasingly found in the human-dominated landscapes outside protected areas, creating the potential for serious economic impacts and tragic consequences for both humans and elephants. Managing elephants and other wide-ranging species requires information about population and group sizes, demography, distribution and habitat connectivity. Although we can view African savannah elephants (Loxodonta africana) from the air and estimate population sizes and movements through direct observations, these data are especially difficult to obtain for African forest elephants (Loxodonta cyclotis) and Asian elephants (Elephas maximus), as aerial surveys cannot detect animals under the closed canopy and ground surveys cannot be performed due to the dense vegetation. The case studies presented here illustrate the power of genetic studies using DNA obtained from non-invasively collected samples to provide biologists with important insights at the individual and population levels. In the Rift Valley of southern Kenya, the use of these methods allowed researchers to infer the movement patterns, demography and stress levels of a recently reestablished population of African savannah elephants on Maasai community land. Although behavioral studies of African forest elephants have suggested that social groups are predominately made up of a single female and her offspring, genetic analyses revealed evidence of weak, but significant, kin-based social structure comparable to the family groups observed in African savannah elephants. For the Asian elephant population of the Nakai Plateau, Lao PDR, genetic analyses allowed researchers to infer population size and demographic structure, and to estimate the level of genetic diversity. Despite having a considerably smaller population size than those found in India and Sri Lanka, the genetic diversity of the Nakai elephants continues to be among the highest reported in Asian elephants, highlighting the conservation value of this and other small, isolated populations in southeast Asia. These studies illustrate the breadth of information that can be obtained and highlight the use of genetic data in the conservation of these keystone species.

Habitat fragmentation can play a major role in the reduction of genetic diversity among wildlife populations. The Ruaha-Rungwa and Katavi-Rukwa ecosystems in south-western Tanzania comprise one of the world’s largest remaining African savannah elephant metapopulation but are increasingly threatened by loss of connectivity and poaching for ivory. To investigate the genetic structure of populations, we compared the genotypes for nine microsatellite loci in the western, central and eastern populations. We found evidence of genetic differentiation among the three populations, but the levels were low and mostly concerned the younger cohort, suggesting recent divergence probably resulting from habitat loss between the two ecosystems. We identified weak isolation by distance, suggesting higher gene flow among individuals located less than 50km apart. In a long-lived species with overlapping generations, it takes a long time to develop genetic substructure even when there are substantial obstacles to migration. Thus, in these recently fragmented populations, inbreeding (and the loss of heterozygosity) may be less of an immediate concern than the loss of adults due to illegal hunting.

Patterns of human development are shifting from concentrated housing toward sprawled housing intermixed with natural land cover, and wildlife species increasingly persist in close proximity to housing, roads, and other anthropogenic features. These associations can alter population dynamics and evolutionary trajectories. Large carnivores increasingly occupy urban peripheries, yet the ecological consequences for populations established entirely within urban and exurban landscapes are largely unknown. We applied a spatial and landscape genetics approach, using noninvasively collected genetic data, to identify differences in black bear spatial genetic patterns across a rural‐to‐urban gradient and quantify how development affects spatial genetic processes. We quantified differences in black bear dispersal, spatial genetic structure, and migration between differing levels of development within a population primarily occupying areas with >6 houses/km2 in western Connecticut. Increased development disrupted spatial genetic structure, and we found an association between increased housing densities and longer dispersal. We also found evidence that roads limited gene flow among bears in more rural areas, yet had no effect among bears in more developed ones. These results suggest dispersal behavior is condition‐dependent and indicate the potential for landscapes intermixing development and natural land cover to facilitate shifts toward increased dispersal. These changes can affect patterns of range expansion and the phenotypic and genetic composition of surrounding populations. We found evidence that subpopulations occupying more developed landscapes may be sustained by male‐biased immigration, creating potentially detrimental demographic shifts.