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Locomotor constraints favour the evolution of the human pygmy phenotype in tropical rainforests

Venkataraman VV, Yegian AK, Wallace IJ, Holowka NB, Tacey I, Gurven M, et al.

Proc Biol Sci, 2018 11 07;285(1890).
PMID: 30404871 DOI: 10.1098/rspb.2018.1492

The convergent evolution of the human pygmy phenotype in tropical rainforests is widely assumed to reflect adaptation in response to the distinct ecological challenges of this habitat (e.g. high levels of heat and humidity, high pathogen load, low food availability, and dense forest structure), yet few precise adaptive benefits of this phenotype have been proposed. Here, we describe and test a biomechanical model of how the rainforest environment can alter gait kinematics such that short stature is advantageous in dense habitats. We hypothesized that environmental constraints on step length in rainforests alter walking mechanics such that taller individuals are expected to walk more slowly due to their inability to achieve preferred step lengths in the rainforest. We tested predictions from this model with experimental field data from two short-statured populations that regularly forage in the rainforest: the Batek of Peninsular Malaysia and the Tsimane of the Bolivian Amazon. In accordance with model expectations, we found stature-dependent constraints on step length in the rainforest and concomitant reductions in walking speed that are expected to compromise foraging efficiency. These results provide the first evidence that the human pygmy phenotype is beneficial in terms of locomotor performance and highlight the value of applying laboratory-derived biomechanical models to field settings for testing evolutionary hypotheses.

Matched MeSH terms: Adaptation, Biological*
Complete genome of Jeotgalibacillus malaysiensis D5(T) consisting of a chromosome and a circular megaplasmid

Goh KM, Chan KG, Yaakop AS, Ee R

J Biotechnol, 2015 Jun 20;204:13-4.
PMID: 25858153 DOI: 10.1016/j.jbiotec.2015.03.007

Jeotgalibacillus spp. are halophilic bacteria within the family Planococcaceae. No genomes of Jeotgalibacillus spp. have been reported to date, and their metabolic pathways are unknown. How the bacteria survive in hypertonic conditions such as seawater is yet to be discovered. As only few studies have been conducted on Jeotgalibacillus spp., potential applications of these bacteria are unknown. Here, we present the complete genome of J. malaysiensis D5(T) (=DSM 28777(T) =KCTC 33350(T)), which is invaluable in identifying interesting applications for this genus.

Matched MeSH terms: Adaptation, Biological/genetics*
Fulltext Shared Signature of Recent Positive Selection on the TSBP1-BTNL2-HLA-DRA Genes in Five Native Populations from North Borneo

Hoh BP, Zhang X, Deng L, Yuan K, Yew CW, Saw WY, et al.

Genome Biol Evol, 2020 12 06;12(12):2245-2257.
PMID: 33022050 DOI: 10.1093/gbe/evaa207

North Borneo (NB) is home to more than 40 native populations. These natives are believed to have undergone local adaptation in response to environmental challenges such as the mosquito-abundant tropical rainforest. We attempted to trace the footprints of natural selection from the genomic data of NB native populations using a panel of ∼2.2 million genome-wide single nucleotide polymorphisms. As a result, an ∼13-kb haplotype in the Major Histocompatibility Complex Class II region encompassing candidate genes TSBP1-BTNL2-HLA-DRA was identified to be undergoing natural selection. This putative signature of positive selection is shared among the five NB populations and is estimated to have arisen ∼5.5 thousand years (∼220 generations) ago, which coincides with the period of Austronesian expansion. Owing to the long history of endemic malaria in NB, the putative signature of positive selection is postulated to be driven by Plasmodium parasite infection. The findings of this study imply that despite high levels of genetic differentiation, the NB populations might have experienced similar local genetic adaptation resulting from stresses of the shared environment.

Matched MeSH terms: Adaptation, Biological/genetics
Genomic analyses of five Roseivirga species: Insights into marine adaptation

Selvaratnam C, Thevarajoo S, Goh KM, Chan KG, Chong CS

Mar Genomics, 2018 Apr;38:97-101.
PMID: 29306571 DOI: 10.1016/j.margen.2017.12.008

To date, the genus Roseivirga consists of six species with one subspecies and is one of the least-studied genera among the family Flammeovirgaceae. In order to further explore this genus, the genome sequences of five Roseivirga spp. were compared and described in this study. The Roseivirga genomes have similar sizes in the range of 4.08-4.47Mb with an average of 4.22Mb. Several key proteins related to osmotic stress adaptation were identified in Roseivirga spp. including betaine transporter, choline dehydrogenase, and glutamate synthases. Significant amount of proteins associated with amino acid transport and metabolism were also present in Roseivirga genome. All five Roseivirga spp. were able to grow in medium contained casamino acids (mixture of amino acids) as sole carbon or nitrogen sources. Taken together, these findings suggested the potential role of Roseivirga in decomposing organic nitrogen matter in marine environment.

Matched MeSH terms: Adaptation, Biological/genetics*
Fulltext Demographic History and Genetic Adaptation in the Himalayan Region Inferred from Genome-Wide SNP Genotypes of 49 Populations

Arciero E, Kraaijenbrink T, Asan, Haber M, Mezzavilla M, Ayub Q, et al.

Mol Biol Evol, 2018 Aug 01;35(8):1916-1933.
PMID: 29796643 DOI: 10.1093/molbev/msy094

We genotyped 738 individuals belonging to 49 populations from Nepal, Bhutan, North India, or Tibet at over 500,000 SNPs, and analyzed the genotypes in the context of available worldwide population data in order to investigate the demographic history of the region and the genetic adaptations to the harsh environment. The Himalayan populations resembled other South and East Asians, but in addition displayed their own specific ancestral component and showed strong population structure and genetic drift. We also found evidence for multiple admixture events involving Himalayan populations and South/East Asians between 200 and 2,000 years ago. In comparisons with available ancient genomes, the Himalayans, like other East and South Asian populations, showed similar genetic affinity to Eurasian hunter-gatherers (a 24,000-year-old Upper Palaeolithic Siberian), and the related Bronze Age Yamnaya. The high-altitude Himalayan populations all shared a specific ancestral component, suggesting that genetic adaptation to life at high altitude originated only once in this region and subsequently spread. Combining four approaches to identifying specific positively selected loci, we confirmed that the strongest signals of high-altitude adaptation were located near the Endothelial PAS domain-containing protein 1 and Egl-9 Family Hypoxia Inducible Factor 1 loci, and discovered eight additional robust signals of high-altitude adaptation, five of which have strong biological functional links to such adaptation. In conclusion, the demographic history of Himalayan populations is complex, with strong local differentiation, reflecting both genetic and cultural factors; these populations also display evidence of multiple genetic adaptations to high-altitude environments.

Matched MeSH terms: Adaptation, Biological*
Spectacular Batesian mimicry in ants

Ito F, Hashim R, Huei YS, Kaufmann E, Akino T, Billen J

Naturwissenschaften, 2004 Oct;91(10):481-4.
PMID: 15729761

The mechanism by which palatable species take advantage of their similarity in appearance to those that are unpalatable, in order to avoid predation, is called Batesian mimicry. Several arthropods are thought to be Batesian mimics of social insects; however, social insects that are Batesian mimics among themselves are rare. In Malaysia we found a possible Batesian mimic in an arboreal ant species, Camponotus sp., which was exclusively observed on foraging trails of the myrmicine ant Crematogaster inflata. The bright yellow and black colouring pattern, as well as the walking behaviour, were very similar in both species. We observed general interactions between the two species, and tested their palatability and the significance of the remarkably similar visual colour patterns for predator avoidance. Prey offered to C. inflata was also eaten by Camponotus workers in spite of their being attacked by C. inflata, indicating that Camponotus sp. is a commensal of C. inflata. An experiment with chicks as potential predators suggests that Camponotus sp. is palatable whereas C. inflata is unpalatable. After tasting C. inflata, the chicks no longer attacked Camponotus sp., indicating that Camponotus sp. is a Batesian mimic of Crematogaster inflata.

Matched MeSH terms: Adaptation, Biological
Global metabolic network reorganization by adaptive mutations allows fast growth of Escherichia coli on glycerol

Cheng KK, Lee BS, Masuda T, Ito T, Ikeda K, Hirayama A, et al.

Nat Commun, 2014;5:3233.
PMID: 24481126 DOI: 10.1038/ncomms4233

Comparative whole-genome sequencing enables the identification of specific mutations during adaptation of bacteria to new environments and allelic replacement can establish their causality. However, the mechanisms of action are hard to decipher and little has been achieved for epistatic mutations, especially at the metabolic level. Here we show that a strain of Escherichia coli carrying mutations in the rpoC and glpK genes, derived from adaptation in glycerol, uses two distinct metabolic strategies to gain growth advantage. A 27-bp deletion in the rpoC gene first increases metabolic efficiency. Then, a point mutation in the glpK gene promotes growth by improving glycerol utilization but results in increased carbon wasting as overflow metabolism. In a strain carrying both mutations, these contrasting carbon/energy saving and wasting mechanisms work together to give an 89% increase in growth rate. This study provides insight into metabolic reprogramming during adaptive laboratory evolution for fast cellular growth.

Matched MeSH terms: Adaptation, Biological*
Geographical variation of skull morphology and its functional significances in the red-cheeked squirrel

Endo H, Kimura J, Oshida T, Stafford BJ, Rerkamnuaychoke W, Nishida T, et al.

J Vet Med Sci, 2003 Nov;65(11):1179-83.
PMID: 14665745

Skulls of the red-cheeked squirrel (Dremomys rufigenis) from various geographical locations: Malaysia (peninsular area), Vietnam (south district)-Laos, and Thailand (north district) were osteometrically examined. The skull size of the squirrels in the southern (Malaysia) population was fundamentally larger than that in the northern (Vietnam, Laos and Thailand) populations. The proportion indices indicated that the splanchnocranium was relatively longer in the Malaysia population, and that the interorbital space was narrower in Vietnam-Laos, and Thailand populations. We suggest that the long nose and laterally-oriented orbits in the skull may be better adapted for terrestrial-insectivorous life in the Malaysia population and the binocular sense facilitated by rostrally-oriented eyes contributes to the arboreal-fruit eating behavior in the two northern populations. The Malaysia population was clearly distinguished from the other populations by the principal component analysis. We suggest that the geographical barrier of the Isthmus of Kra influences the morphological variation of the skull among the squirrel populations.

Matched MeSH terms: Adaptation, Biological*
Fulltext Enhancement of the production of L-glutaminase, an anticancer enzyme, from Aeromonas veronii by adaptive and induced mutation techniques

Jesuraj SAV, Sarker MMR, Ming LC, Praya SMJ, Ravikumar M, Wui WT

PLoS One, 2017;12(8):e0181745.
PMID: 28813436 DOI: 10.1371/journal.pone.0181745

Microbial anti-cancer enzymes have been proven to be effective and economical agents for cancer treatment. Aeromonas veronii has been identified as a microorganism with the potential to produce L-glutaminase, an anticancer agent effective against acute lymphocytic leukaemia. In this study, a selective medium of Aeromonas veronii was used to culture the microorganism. Strain improvement was done by adaptive and induced mutational techniques. A selective minimal agar media was incorporated for the growth of the strain which further supports adaptive mutation. Strains were also UV-irradiated and successively treated with N-methyl-N'-nitro-N-nitrosoguanidine to find a resilient strain capable of producing L-glutaminase efficiently. The Plackett-Burman design and central composite designs were used to screen and optimize additional carbon and nitrogen sources. Adaptive mutation resulted in promising yield improvements compared to native strain (P<0.001). The mean yield of 30 treated colonies from the induced mutation was significantly increased compared to the non-induced strain (P< 0.001). The economically feasible statistical designs were found to reinforce each other in order to maximize the yield of the enzyme. The interactions of nutrient factors were understood from the 3D response surface plots. The model was found to be a perfect fit in terms of maximizing enzyme yield, with the productivity improving at every stage to a fourfold output of enzyme (591.11 ±7.97 IU/mL) compared to the native strain (135±3.51 IU/mL).

Matched MeSH terms: Adaptation, Biological*
Fulltext Duplicated female receptacle organs for traumatic insemination in the tropical bed bug Cimex hemipterus: adaptive variation or malformation?

Kamimura Y, Mitsumoto H, Lee CY

PLoS One, 2014;9(2):e89265.
PMID: 24586643 DOI: 10.1371/journal.pone.0089265

During mating, male bed bugs (Cimicidae) pierce the female abdomen to inject sperm using their needle-like genitalia. Females evolved specialized paragenital organs (the spermalege and associated structures) to receive traumatically injected ejaculates. In Leptocimex duplicatus, the spermalege is duplicated, but the evolutionary significance of this is unclear. In Cimex hemipterus and C. lectularius, in which females normally develop a single spermalege on the right side of the abdomen, similar duplication sometimes occurs. Using these aberrant morphs (D-females) of C. hemipterus, we tested the hypothesis that both of the duplicated spermaleges are functionally competent. Scars on female abdominal exoskeletons indicated frequent misdirected piercing by male genitalia. However, the piercing sites showed a highly biased distribution towards the right side of the female body. A mating experiment showed that when the normal insemination site (the right-side spermalege) was artificially covered, females remained unfertilized. This was true even when females also had a spermalege on the left side (D-females). This result was attributed to handedness in male mating behavior. Irrespective of the observed disuse of the left-side spermalege by males for insemination, histological examination failed to detect any differences between the right-side and left-side spermaleges. Moreover, an artificial insemination experiment confirmed that spermatozoa injected into the left-side spermalege show apparently normal migration behavior to the female reproductive organs, indicating an evolutionary potential for functionally-competent duplicated spermaleges. We discuss possible mechanisms for the evolutionary maintenance of D-females and propose a plausible route to the functionally-competent duplicated spermaleges observed in L. duplicatus.

Matched MeSH terms: Adaptation, Biological/physiology*
Fulltext FineMAV: prioritizing candidate genetic variants driving local adaptations in human populations

Szpak M, Mezzavilla M, Ayub Q, Chen Y, Xue Y, Tyler-Smith C

Genome Biol, 2018 Jan 17;19(1):5.
PMID: 29343290 DOI: 10.1186/s13059-017-1380-2

We present a new method, Fine-Mapping of Adaptive Variation (FineMAV), which combines population differentiation, derived allele frequency, and molecular functionality to prioritize positively selected candidate variants for functional follow-up. We calibrate and test FineMAV using eight experimentally validated "gold standard" positively selected variants and simulations. FineMAV has good sensitivity and a low false discovery rate. Applying FineMAV to the 1000 Genomes Project Phase 3 SNP dataset, we report many novel selected variants, including ones in TGM3 and PRSS53 associated with hair phenotypes that we validate using available independent data. FineMAV is widely applicable to sequence data from both human and other species.

Matched MeSH terms: Adaptation, Biological/genetics*
Size and shape of Kedah-Kelantan cows

Aman A, Brown CJ, Johnson Z

Growth, 1978 Dec;42(4):486-94.
PMID: 750311

Body weight and nine body measurements were recorded on 79 mature Kedah-Kelantan cows at two locations. The Kedah-Kelantan is an indigenous cattle of Malaysia. A principal component analysis was used to study size and shape as indicated by the dependence structure among measurements. The total variation among measurements associated with the first principal component which was interpreted as a measure of general size was 40.8%. The second principal component contrasted cows tall at the withers, and deep at the chest with top line sloping downward and under line sloping upward from front to rear with those having less wither height and chest depth and straighter lines. This contrast accounted for 14.3% of the variation in body dimensions. The third principal component contrasted long, narrow, and deeper cows with a more compact type. This contrast accounted for 10.7% of the variation in body dimensions.

Matched MeSH terms: Adaptation, Biological
Fulltext Identification of four functionally important microRNA families with contrasting differential expression profiles between drought-tolerant and susceptible rice leaf at vegetative stage

Cheah BH, Nadarajah K, Divate MD, Wickneswari R

BMC Genomics, 2015;16:692.
PMID: 26369665 DOI: 10.1186/s12864-015-1851-3

Developing drought-tolerant rice varieties with higher yield under water stressed conditions provides a viable solution to serious yield-reduction impact of drought. Understanding the molecular regulation of this polygenic trait is crucial for the eventual success of rice molecular breeding programmes. microRNAs have received tremendous attention recently due to its importance in negative regulation. In plants, apart from regulating developmental and physiological processes, microRNAs have also been associated with different biotic and abiotic stresses. Hence here we chose to analyze the differential expression profiles of microRNAs in three drought treated rice varieties: Vandana (drought-tolerant), Aday Sel (drought-tolerant) and IR64 (drought-susceptible) in greenhouse conditions via high-throughput sequencing.

Matched MeSH terms: Adaptation, Biological/genetics*
Fulltext A 3.4-kb Copy-Number Deletion near EPAS1 Is Significantly Enriched in High-Altitude Tibetans but Absent from the Denisovan Sequence

Lou H, Lu Y, Lu D, Fu R, Wang X, Feng Q, et al.

Am J Hum Genet, 2015 Jul 02;97(1):54-66.
PMID: 26073780 DOI: 10.1016/j.ajhg.2015.05.005

Tibetan high-altitude adaptation (HAA) has been studied extensively, and many candidate genes have been reported. Subsequent efforts targeting HAA functional variants, however, have not been that successful (e.g., no functional variant has been suggested for the top candidate HAA gene, EPAS1). With WinXPCNVer, a method developed in this study, we detected in microarray data a Tibetan-enriched deletion (TED) carried by 90% of Tibetans; 50% were homozygous for the deletion, whereas only 3% carried the TED and 0% carried the homozygous deletion in 2,792 worldwide samples (p < 10(-15)). We employed long PCR and Sanger sequencing technologies to determine the exact copy number and breakpoints of the TED in 70 additional Tibetan and 182 diverse samples. The TED had identical boundaries (chr2: 46,694,276-46,697,683; hg19) and was 80 kb downstream of EPAS1. Notably, the TED was in strong linkage disequilibrium (LD; r(2) = 0.8) with EPAS1 variants associated with reduced blood concentrations of hemoglobin. It was also in complete LD with the 5-SNP motif, which was suspected to be introgressed from Denisovans, but the deletion itself was absent from the Denisovan sequence. Correspondingly, we detected that footprints of positive selection for the TED occurred 12,803 (95% confidence interval = 12,075-14,725) years ago. We further whole-genome deep sequenced (>60×) seven Tibetans and verified the TED but failed to identify any other copy-number variations with comparable patterns, giving this TED top priority for further study. We speculate that the specific patterns of the TED resulted from its own functionality in HAA of Tibetans or LD with a functional variant of EPAS1.

Matched MeSH terms: Adaptation, Biological/genetics*
Fulltext Emergence and adaptive evolution of Nipah virus

Li K, Yan S, Wang N, He W, Guan H, He C, et al.

Transbound Emerg Dis, 2020 Jan;67(1):121-132.
PMID: 31408582 DOI: 10.1111/tbed.13330

Since its first emergence in 1998 in Malaysia, Nipah virus (NiV) has become a great threat to domestic animals and humans. Sporadic outbreaks associated with human-to-human transmission caused hundreds of human fatalities. Here, we collected all available NiV sequences and combined phylogenetics, molecular selection, structural biology and receptor analysis to study the emergence and adaptive evolution of NiV. NiV can be divided into two main lineages including the Bangladesh and Malaysia lineages. We formly confirmed a significant association with geography which is probably the result of long-term evolution of NiV in local bat population. The two NiV lineages differ in many amino acids; one change in the fusion protein might be involved in its activation via binding to the G protein. We also identified adaptive and positively selected sites in many viral proteins. In the receptor-binding G protein, we found that sites 384, 386 and especially 498 of G protein might modulate receptor-binding affinity and thus contribute to the host jump from bats to humans via the adaption to bind the human ephrin-B2 receptor. We also found that site 1645 in the connector domain of L was positive selected and involved in adaptive evolution; this site might add methyl groups to the cap structure present at the 5'-end of the RNA and thus modulate its activity. This study provides insight to assist the design of early detection methods for NiV to assess its epidemic potential in humans.

Matched MeSH terms: Adaptation, Biological*
Fulltext Molecular analysis of asymptomatic bacteriuria Escherichia coli strain VR50 reveals adaptation to the urinary tract by gene acquisition

Beatson SA, Ben Zakour NL, Totsika M, Forde BM, Watts RE, Mabbett AN, et al.

Infect Immun, 2015 May;83(5):1749-64.
PMID: 25667270 DOI: 10.1128/IAI.02810-14

Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli responsible for >80% of all cases. One extreme of UTI is asymptomatic bacteriuria (ABU), which occurs as an asymptomatic carrier state that resembles commensalism. To understand the evolution and molecular mechanisms that underpin ABU, the genome of the ABU E. coli strain VR50 was sequenced. Analysis of the complete genome indicated that it most resembles E. coli K-12, with the addition of a 94-kb genomic island (GI-VR50-pheV), eight prophages, and multiple plasmids. GI-VR50-pheV has a mosaic structure and contains genes encoding a number of UTI-associated virulence factors, namely, Afa (afimbrial adhesin), two autotransporter proteins (Ag43 and Sat), and aerobactin. We demonstrated that the presence of this island in VR50 confers its ability to colonize the murine bladder, as a VR50 mutant with GI-VR50-pheV deleted was attenuated in a mouse model of UTI in vivo. We established that Afa is the island-encoded factor responsible for this phenotype using two independent deletion (Afa operon and AfaE adhesin) mutants. E. coli VR50afa and VR50afaE displayed significantly decreased ability to adhere to human bladder epithelial cells. In the mouse model of UTI, VR50afa and VR50afaE displayed reduced bladder colonization compared to wild-type VR50, similar to the colonization level of the GI-VR50-pheV mutant. Our study suggests that E. coli VR50 is a commensal-like strain that has acquired fitness factors that facilitate colonization of the human bladder.

Matched MeSH terms: Adaptation, Biological*
Differential positive selection of malaria resistance genes in three indigenous populations of Peninsular Malaysia

Liu X, Yunus Y, Lu D, Aghakhanian F, Saw WY, Deng L, et al.

Hum Genet, 2015 Apr;134(4):375-92.
PMID: 25634076 DOI: 10.1007/s00439-014-1525-2

The indigenous populations from Peninsular Malaysia, locally known as Orang Asli, continue to adopt an agro-subsistence nomadic lifestyle, residing primarily within natural jungle habitats. Leading a hunter-gatherer lifestyle in a tropical jungle environment, the Orang Asli are routinely exposed to malaria. Here we surveyed the genetic architecture of individuals from four Orang Asli tribes with high-density genotyping across more than 2.5 million polymorphisms. These tribes reside in different geographical locations in Peninsular Malaysia and belong to three main ethno-linguistic groups, where there is minimal interaction between the tribes. We first dissect the genetic diversity and admixture between the tribes and with neighboring urban populations. Later, by implementing five metrics, we investigated the genome-wide signatures for positive natural selection of these Orang Asli, respectively. Finally, we searched for evidence of genomic adaptation to the pressure of malaria infection. We observed that different evolutionary responses might have emerged in the different Orang Asli communities to mitigate malaria infection.

Matched MeSH terms: Adaptation, Biological/genetics
The status of the Japanese and East Asian bats of the genus Myotis (Vespertilionidae) based on mitochondrial sequences

Kawai K, Nikaido M, Harada M, Matsumura S, Lin LK, Wu Y, et al.

Mol Phylogenet Evol, 2003 Aug;28(2):297-307.
PMID: 12878466

The genus Myotis includes the largest number of species in the family Vespertilionidae (Chiroptera), and its members are distributed throughout most of the world. To re-evaluate the phylogenetic position of East Asian Myotis species with respect to Myotis species worldwide, we analyzed mitochondrial gene sequences of NADH dehydrogenase subunit 1 and cytochrome b from 24 East Asian individuals as well as 42 vespertilionid bats determined previously. The results suggest that: (1) some individuals having the same species name in Europe and Japan do not form a monophyletic clade, indicating that some bat species exhibit morphological convergence, (2) Japanese Myotis mystacinus forms a sister relationship with Myotis brandtii (Palaearctic), and both species are included in the American clade implying that an ancestor of these species originated in North America, and (3) the Black whiskered bat, Myotis pruinosus, is endemic to Japan and forms sister relationships with Myotis yanbarensis and Myotis montivagus collected from Okinawa (Japan) and Selangor (Malaysia), respectively, implying that M. pruinosus originated from the south. The systematics of Japanese and East Asian Myotis bats were revisited by considering their phylogenetic relationships. Our study provides the first extensive phylogenetic hypothesis of the genus Myotis that includes East Asian and Japanese species.

Matched MeSH terms: Adaptation, Biological
Fulltext Protective role of the vulture facial skin and gut microbiomes aid adaptation to scavenging

Zepeda Mendoza ML, Roggenbuck M, Manzano Vargas K, Hansen LH, Brunak S, Gilbert MTP, et al.

Acta Vet Scand, 2018 Oct 11;60(1):61.
PMID: 30309375 DOI: 10.1186/s13028-018-0415-3

BACKGROUND: Vultures have adapted the remarkable ability to feed on carcasses that may contain microorganisms that would be pathogenic to most other animals. The holobiont concept suggests that the genetic basis of such adaptation may not only lie within their genomes, but additionally in their associated microbes. To explore this, we generated shotgun DNA sequencing datasets of the facial skin and large intestine microbiomes of the black vulture (Coragyps atratus) and the turkey vulture (Cathartes aura). We characterized the functional potential and taxonomic diversity of their microbiomes, the potential pathogenic challenges confronted by vultures, and the microbial taxa and genes that could play a protective role on the facial skin and in the gut.
RESULTS: We found microbial taxa and genes involved in diseases, such as dermatitis and pneumonia (more abundant on the facial skin), and gas gangrene and food poisoning (more abundant in the gut). Interestingly, we found taxa and functions with potential for playing beneficial roles, such as antilisterial bacteria in the gut, and genes for the production of antiparasitics and insecticides on the facial skin. Based on the identified phages, we suggest that phages aid in the control and possibly elimination, as in phage therapy, of microbes reported as pathogenic to a variety of species. Interestingly, we identified Adineta vaga in the gut, an invertebrate that feeds on dead bacteria and protozoans, suggesting a defensive predatory mechanism. Finally, we suggest a colonization resistance role through biofilm formation played by Fusobacteria and Clostridia in the gut.
CONCLUSIONS: Our results highlight the importance of complementing genomic analyses with metagenomics in order to obtain a clearer understanding of the host-microbial alliance and show the importance of microbiome-mediated health protection for adaptation to extreme diets, such as scavenging.

Matched MeSH terms: Adaptation, Biological
Fulltext De novo sequencing, assembly and analysis of eight different transcriptomes from the Malayan pangolin

Mohamed Yusoff A, Tan TK, Hari R, Koepfli KP, Wee WY, Antunes A, et al.

Sci Rep, 2016 09 13;6:28199.
PMID: 27618997 DOI: 10.1038/srep28199

Pangolins are scale-covered mammals, containing eight endangered species. Maintaining pangolins in captivity is a significant challenge, in part because little is known about their genetics. Here we provide the first large-scale sequencing of the critically endangered Manis javanica transcriptomes from eight different organs using Illumina HiSeq technology, yielding ~75 Giga bases and 89,754 unigenes. We found some unigenes involved in the insect hormone biosynthesis pathway and also 747 lipids metabolism-related unigenes that may be insightful to understand the lipid metabolism system in pangolins. Comparative analysis between M. javanica and other mammals revealed many pangolin-specific genes significantly over-represented in stress-related processes, cell proliferation and external stimulus, probably reflecting the traits and adaptations of the analyzed pregnant female M. javanica. Our study provides an invaluable resource for future functional works that may be highly relevant for the conservation of pangolins.

Matched MeSH terms: Adaptation, Biological

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