1
|
Jiao H, Wang Q, Wang BJ, Li K, Lövy M, Nevo E, Li Q, Su W, Jiang P, Zhao H. Local adaptation of bitter taste and ecological speciation in a wild mammal. Mol Biol Evol 2021; 38:4562-4572. [PMID: 34240186 PMCID: PMC8476172 DOI: 10.1093/molbev/msab205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sensory systems are attractive evolutionary models to address how organisms adapt to local environments that can cause ecological speciation. However, tests of these evolutionary models have focused on visual, auditory, and olfactory senses. Here, we show local adaptation of bitter taste receptor genes in two neighboring populations of a wild mammal—the blind mole rat Spalax galili—that show ecological speciation in divergent soil environments. We found that basalt-type bitter receptors showed higher response intensity and sensitivity compared with chalk-type ones using both genetic and cell-based functional analyses. Such functional changes could help animals adapted to basalt soil select plants with less bitterness from diverse local foods, whereas a weaker reception to bitter taste may allow consumption of a greater range of plants for animals inhabiting chalk soil with a scarcity of food supply. Our study shows divergent selection on food resources through local adaptation of bitter receptors, and suggests that taste plays an important yet underappreciated role in speciation.
Collapse
Affiliation(s)
- Hengwu Jiao
- Department of Ecology, Tibetan Centre for Ecology and Conservation at Wuhan University-Tibet University, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Qian Wang
- Department of Ecology, Tibetan Centre for Ecology and Conservation at Wuhan University-Tibet University, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Bing-Jun Wang
- Department of Ecology, Tibetan Centre for Ecology and Conservation at Wuhan University-Tibet University, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Kexin Li
- Institute of Evolution, University of Haifa, Mount Carmel, Haifa, 3498838, Israel.,State Key Laboratory of Grassland Agro-ecosystem, Institute of Innovation Ecology, Lanzhou University, Lanzhou, 730000, China
| | - Matěj Lövy
- Department of Zoology, Faculty of Science, University of South Bohemia, České Budějovice, 37005, Czech Republic
| | - Eviatar Nevo
- Institute of Evolution, University of Haifa, Mount Carmel, Haifa, 3498838, Israel
| | - Qiyang Li
- Department of Ecology, Tibetan Centre for Ecology and Conservation at Wuhan University-Tibet University, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Wenchuan Su
- Department of Ecology, Tibetan Centre for Ecology and Conservation at Wuhan University-Tibet University, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Peihua Jiang
- Monell Chemical Senses Center, Philadelphia, Pennsylvania, 19104, USA
| | - Huabin Zhao
- Department of Ecology, Tibetan Centre for Ecology and Conservation at Wuhan University-Tibet University, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.,Research Center for Ecology, College of Science, Tibet University, Lhasa, 850000, China
| |
Collapse
|
2
|
Ali MA, Wang Y, Qin Z, Yuan X, Zhang Y, Zeng C. Odorant and Taste Receptors in Sperm Chemotaxis and Cryopreservation: Roles and Implications in Sperm Capacitation, Motility and Fertility. Genes (Basel) 2021; 12:genes12040488. [PMID: 33801624 PMCID: PMC8065900 DOI: 10.3390/genes12040488] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/24/2021] [Accepted: 03/24/2021] [Indexed: 11/24/2022] Open
Abstract
Sperm chemotaxis, which guide sperm toward oocyte, is tightly associated with sperm capacitation, motility, and fertility. However, the molecular mechanism of sperm chemotaxis is not known. Reproductive odorant and taste receptors, belong to G-protein-coupled receptors (GPCR) super-family, cause an increase in intracellular Ca2+ concentration which is pre-requisite for sperm capacitation and acrosomal reaction, and result in sperm hyperpolarization and increase motility through activation of Ca2+-dependent Cl¯ channels. Recently, odorant receptors (ORs) in olfactory transduction pathway were thought to be associated with post-thaw sperm motility, freeze tolerance or freezability and cryo-capacitation-like change during cryopreservation. Investigation of the roles of odorant and taste receptors (TRs) is important for our understanding of the freeze tolerance or freezability mechanism and improve the motility and fertility of post-thaw sperm. Here, we reviewed the roles, mode of action, impact of odorant and taste receptors on sperm chemotaxis and post-thaw sperm quality.
Collapse
Affiliation(s)
- Malik Ahsan Ali
- College of Animal Science and Technology and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; (Y.W.); (Z.Q.); (X.Y.); (Y.Z.)
- Department of Theriogenology, Riphah College of Veterinary Sciences, Lahore 54000, Punjab, Pakistan;
- Department of Theriogenology, Faculty of Veterinary Science, University of Agriculture, Faisalabad 38000, Punjab, Pakistan
| | - Yihan Wang
- College of Animal Science and Technology and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; (Y.W.); (Z.Q.); (X.Y.); (Y.Z.)
| | - Ziyue Qin
- College of Animal Science and Technology and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; (Y.W.); (Z.Q.); (X.Y.); (Y.Z.)
| | - Xiang Yuan
- College of Animal Science and Technology and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; (Y.W.); (Z.Q.); (X.Y.); (Y.Z.)
| | - Yan Zhang
- College of Animal Science and Technology and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; (Y.W.); (Z.Q.); (X.Y.); (Y.Z.)
| | - Changjun Zeng
- College of Animal Science and Technology and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, Sichuan Agricultural University, Chengdu 611130, Sichuan, China; (Y.W.); (Z.Q.); (X.Y.); (Y.Z.)
- Correspondence: ; Tel./Fax: +86-28-86291010
| |
Collapse
|
3
|
Liang Q, Shu F, Dong X, Feng P. The evolution of a bitter taste receptor gene in primates. Chem Senses 2021; 46:6449468. [PMID: 34864939 DOI: 10.1093/chemse/bjab049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Bitter taste perception is critical to prevent animals from ingesting potentially harmful substances. The aim of this study was to characterize the evolution of T2R4 and test the hypothesis that different regions of the T2R gene are subject to disparate selective pressures, with extracellular regions (ECs) being erratic while transmembrane (TMs) and intracellular regions (ICs) being constrained. Thus, we examined the selective pressures acting on T2R4 and its different regions in 37 primates, and discovered that T2R4 and ECs were subject to neutral evolution and purifying selection, respectively, whereas both TMs and ICs showed purifying selection, as suggested by the hypothesis. We attribute this result to the relatively conservative property of T2R4 gene and the limited number of bitter tastants that T2R4 can respond to. Furthermore, we found that positive selection had acted on the first loop of extracellular regions (EL1). In contrast, the second loop (EL2) and transmembrane region-3, -6, -7 (TM367) were subject to purifying selection, and the third loop (EL3) was subject to neutral evolution. This discovery is probably because EL2, EL3, and TMs play a crucial role in the ligand-binding process, and EL1 is involved in the tastant recognition process. We further tested whether the ω of T2R4 differs among species with different diets and found that a specialized diet affected the evolution of T2R4. Feeding habits, fewer T2Rs, and a dietary shift may account for the results. This study can help to uncover the evolution of T2Rs during the primate evolutionary course.
Collapse
Affiliation(s)
- Qiufang Liang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, Guangxi, China.,Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi, China
| | - Fanglan Shu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, Guangxi, China.,Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi, China
| | - Xiaoyan Dong
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, Guangxi, China.,Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi, China
| | - Ping Feng
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin, Guangxi, China.,Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University, Guilin, Guangxi, China
| |
Collapse
|
4
|
Abstract
While non-human primate studies have long been conducted in laboratories, and more recently at zoological parks, sanctuaries are increasingly considered a viable setting for research. Accredited sanctuaries in non-range countries house thousands of primates formerly used as subjects of medical research, trained performers or personal pets. In range countries, however, sanctuaries typically house orphaned primates confiscated from illegal poaching and the bushmeat and pet trafficking trades. Although the primary mission of these sanctuaries is to rescue and rehabilitate residents, many of these organizations are increasingly willing to participate in non-invasive research. Notably, from a scientific standpoint, most sanctuaries provide potential advantages over traditional settings, such as large, naturalistic physical and social environments which may result in more relevant models of primates' free-ranging wild counterparts than other captive settings. As a result, an impressive scope of research in the fields of primate behaviour, cognition, veterinary science, genetics and physiology have been studied in sanctuaries. In this review, we examine the range and form of research that has been conducted at accredited sanctuaries around the world. We also describe the potential challenges of sanctuary-based work and the considerations that external researchers may face when deciding to collaborate with primate sanctuaries on their research projects.
Collapse
Affiliation(s)
- Stephen R Ross
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, 2001 North Clark St., Chicago, IL 60614, USA
| | - Jesse G Leinwand
- Lester E. Fisher Center for the Study and Conservation of Apes, Lincoln Park Zoo, 2001 North Clark St., Chicago, IL 60614, USA
| |
Collapse
|
5
|
Humans and Chimpanzees Display Opposite Patterns of Diversity in Arylamine N-Acetyltransferase Genes. G3-GENES GENOMES GENETICS 2019; 9:2199-2224. [PMID: 31068377 PMCID: PMC6643899 DOI: 10.1534/g3.119.400223] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Among the many genes involved in the metabolism of therapeutic drugs, human arylamine N-acetyltransferases (NATs) genes have been extensively studied, due to their medical importance both in pharmacogenetics and disease epidemiology. One member of this small gene family, NAT2, is established as the locus of the classic human acetylation polymorphism in drug metabolism. Current hypotheses hold that selective processes favoring haplotypes conferring lower NAT2 activity have been operating in modern humans’ recent history as an adaptation to local chemical and dietary environments. To shed new light on such hypotheses, we investigated the genetic diversity of the three members of the NAT gene family in seven hominid species, including modern humans, Neanderthals and Denisovans. Little polymorphism sharing was found among hominids, yet all species displayed high NAT diversity, but distributed in an opposite fashion in chimpanzees and bonobos (Pan genus) compared to modern humans, with higher diversity in Pan species at NAT1 and lower at NAT2, while the reverse is observed in humans. This pattern was also reflected in the results returned by selective neutrality tests, which suggest, in agreement with the predicted functional impact of mutations detected in non-human primates, stronger directional selection, presumably purifying selection, at NAT1 in modern humans, and at NAT2 in chimpanzees. Overall, the results point to the evolution of divergent functions of these highly homologous genes in the different primate species, possibly related to their specific chemical/dietary environment (exposome) and we hypothesize that this is likely linked to the emergence of controlled fire use in the human lineage.
Collapse
|
6
|
The role of GPCRs in bone diseases and dysfunctions. Bone Res 2019; 7:19. [PMID: 31646011 PMCID: PMC6804689 DOI: 10.1038/s41413-019-0059-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 05/22/2019] [Accepted: 05/27/2019] [Indexed: 12/13/2022] Open
Abstract
The superfamily of G protein-coupled receptors (GPCRs) contains immense structural and functional diversity and mediates a myriad of biological processes upon activation by various extracellular signals. Critical roles of GPCRs have been established in bone development, remodeling, and disease. Multiple human GPCR mutations impair bone development or metabolism, resulting in osteopathologies. Here we summarize the disease phenotypes and dysfunctions caused by GPCR gene mutations in humans as well as by deletion in animals. To date, 92 receptors (5 glutamate family, 67 rhodopsin family, 5 adhesion, 4 frizzled/taste2 family, 5 secretin family, and 6 other 7TM receptors) have been associated with bone diseases and dysfunctions (36 in humans and 72 in animals). By analyzing data from these 92 GPCRs, we found that mutation or deletion of different individual GPCRs could induce similar bone diseases or dysfunctions, and the same individual GPCR mutation or deletion could induce different bone diseases or dysfunctions in different populations or animal models. Data from human diseases or dysfunctions identified 19 genes whose mutation was associated with human BMD: 9 genes each for human height and osteoporosis; 4 genes each for human osteoarthritis (OA) and fracture risk; and 2 genes each for adolescent idiopathic scoliosis (AIS), periodontitis, osteosarcoma growth, and tooth development. Reports from gene knockout animals found 40 GPCRs whose deficiency reduced bone mass, while deficiency of 22 GPCRs increased bone mass and BMD; deficiency of 8 GPCRs reduced body length, while 5 mice had reduced femur size upon GPCR deletion. Furthermore, deficiency in 6 GPCRs induced osteoporosis; 4 induced osteoarthritis; 3 delayed fracture healing; 3 reduced arthritis severity; and reduced bone strength, increased bone strength, and increased cortical thickness were each observed in 2 GPCR-deficiency models. The ever-expanding number of GPCR mutation-associated diseases warrants accelerated molecular analysis, population studies, and investigation of phenotype correlation with SNPs to elucidate GPCR function in human diseases.
Collapse
|
7
|
Zhou C, Jin J, Peng C, Wen Q, Wang G, Wei W, Jiang X, Price M, Cui K, Meng Y, Song Z, Li J, Zhang X, Fan Z, Yue B. Comparative genomics sheds light on the predatory lifestyle of accipitrids and owls. Sci Rep 2019; 9:2249. [PMID: 30783131 PMCID: PMC6381159 DOI: 10.1038/s41598-019-38680-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 12/31/2018] [Indexed: 02/08/2023] Open
Abstract
Raptors are carnivorous birds including accipitrids (Accipitridae, Accipitriformes) and owls (Strigiformes), which are diurnal and nocturnal, respectively. To examine the evolutionary basis of adaptations to different light cycles and hunting behavior between accipitrids and owls, we de novo assembled besra (Accipiter virgatus, Accipitridae, Accipitriformes) and oriental scops owl (Otus sunia, Strigidae, Strigiformes) draft genomes. Comparative genomics demonstrated four PSGs (positively selected genes) (XRCC5, PRIMPOL, MDM2, and SIRT1) related to the response to ultraviolet (UV) radiation in accipitrids, and one PSG (ALCAM) associated with retina development in owls, which was consistent with their respective diurnal/nocturnal predatory lifestyles. We identified five accipitrid-specific and two owl-specific missense mutations and most of which were predicted to affect the protein function by PolyPhen-2. Genome comparison showed the diversification of raptor olfactory receptor repertoires, which may reflect an important role of olfaction in their predatory lifestyle. Comparison of TAS2R gene (i.e. linked to tasting bitterness) number in birds with different dietary lifestyles suggested that dietary toxins were a major selective force shaping the diversity of TAS2R repertoires. Fewer TAS2R genes in raptors reflected their carnivorous diet, since animal tissues are less likely to contain toxins than plant material. Our data and findings provide valuable genomic resources for studying the genetic mechanisms of raptors' environmental adaptation, particularly olfaction, nocturnality and response to UV radiation.
Collapse
Affiliation(s)
- Chuang Zhou
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Jiazheng Jin
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Changjun Peng
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Qinchao Wen
- Sichuan Key Laboratory of Conservation Biology on Endangered Wildlife, College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Guannan Wang
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Weideng Wei
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Xue Jiang
- Sichuan Key Laboratory of Conservation Biology on Endangered Wildlife, College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Megan Price
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Kai Cui
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Yang Meng
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Zhaobin Song
- Sichuan Key Laboratory of Conservation Biology on Endangered Wildlife, College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Jing Li
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Xiuyue Zhang
- Sichuan Key Laboratory of Conservation Biology on Endangered Wildlife, College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China
| | - Zhenxin Fan
- Sichuan Key Laboratory of Conservation Biology on Endangered Wildlife, College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China.
| | - Bisong Yue
- Key Laboratory of Bioresources and Ecoenvironment (Ministry of Education), College of Life Sciences, Sichuan University, Chengdu, 610064, P. R. China.
| |
Collapse
|
8
|
Genome wide identification of taste receptor genes in common carp (Cyprinus carpio) and phylogenetic analysis in teleost. Gene 2018; 678:65-72. [DOI: 10.1016/j.gene.2018.07.078] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/21/2018] [Accepted: 07/31/2018] [Indexed: 12/20/2022]
|
9
|
Xue AY, Di Pizio A, Levit A, Yarnitzky T, Penn O, Pupko T, Niv MY. Independent Evolution of Strychnine Recognition by Bitter Taste Receptor Subtypes. Front Mol Biosci 2018; 5:9. [PMID: 29552563 PMCID: PMC5840161 DOI: 10.3389/fmolb.2018.00009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/19/2018] [Indexed: 01/02/2023] Open
Abstract
The 25 human bitter taste receptors (hT2Rs) recognize thousands of structurally and chemically diverse bitter substances. The binding modes of human bitter taste receptors hT2R10 and hT2R46, which are responsible for strychnine recognition, were previously established using site-directed mutagenesis, functional assays, and molecular modeling. Here we construct a phylogenetic tree and reconstruct ancestral sequences of the T2R10 and T2R46 clades. We next analyze the binding sites in view of experimental data to predict their ability to recognize strychnine. This analysis suggests that the common ancestor of hT2R10 and hT2R46 is unlikely to bind strychnine in the same mode as either of its two descendants. Estimation of relative divergence times shows that hT2R10 evolved earlier than hT2R46. Strychnine recognition was likely acquired first by the earliest common ancestor of the T2R10 clade before the separation of primates from other mammals, and was highly conserved within the clade. It was probably independently acquired by the common ancestor of T2R43-47 before the homo-ape speciation, lost in most T2Rs within this clade, but enhanced in the hT2R46 after humans diverged from the rest of primates. Our findings suggest hypothetical strychnine T2R receptors in several species, and serve as an experimental guide for further study. Improved understanding of how bitter taste receptors acquire the ability to be activated by particular ligands is valuable for the development of sensors for bitterness and for potential toxicity.
Collapse
Affiliation(s)
- Ava Yuan Xue
- Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
- The Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Antonella Di Pizio
- Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
- The Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Anat Levit
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, United States
| | - Tali Yarnitzky
- Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
- Tali Yarnitzky Scientific Consulting, Maccabim-Reut, Israel
| | - Osnat Penn
- Modeling, Analysis and Theory Group, Allen Institute for Brain Science, Seattle, WA, United States
| | - Tal Pupko
- The Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Masha Y. Niv
- Robert H. Smith Faculty of Agriculture, Food and Environment, Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot, Israel
- The Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
10
|
Genetic diversity of bitter taste receptor gene family in Sichuan domestic and Tibetan chicken populations. J Genet 2017; 95:675-81. [PMID: 27659339 DOI: 10.1007/s12041-016-0684-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The sense of bitter taste plays a critical role in animals as it can help them to avoid intake of toxic and harmful substances. Previous research had revealed that chicken has only three bitter taste receptor genes (Tas2r1, Tas2r2 and Tas2r7). To better understand the genetic polymorphisms and importance of bitter taste receptor genes (Tas2rs) in chicken, here, we sequenced Tas2rs of 30 Sichuan domestic chickens and 30 Tibetan chickens. Thirteen single-nucleotide polymorphisms (SNPs) including three nonsynonymous mutations (m.359G>C, m.503C>A and m.583A>G) were detected in Tas2r1 (m. is the abbreviation for mutation); three SNPs were detected in Tas2r2, but none of them were missense mutation; eight SNPs were detected in Tas2r7 including six nonsynonymous substitutions (m.178G>A, m.421A>C, m.787C>T, m.832G>T, m.907A>T and m.943G>A). Tajima's D neutral test indicates that there is no population expansion in both populations, and the size of the population is relatively stable. All the three networks indicate that red jungle fowls share haplotypes with domestic chickens. In addition, we found that haplotypes H1 and HE1 were positively associated with high-altitude adaptation, whereas haplotypes H4 and HE4 showed a negative correlation with high-altitude adaptation in Tas2rs. Although, chicken has only three Tas2rs, our results showed that both Sichuan domestic chickens and Tibetan chickens have abundant haplotypes in Tas2rs, especially in Tas2r7, which might help chickens to recognize a wide variety of bitter-tasting compounds.
Collapse
|
11
|
Kawamura S, Melin AD. Evolution of Genes for Color Vision and the Chemical Senses in Primates. EVOLUTION OF THE HUMAN GENOME I 2017. [DOI: 10.1007/978-4-431-56603-8_10] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
|
12
|
Imai H, Suzuki-Hashido N, Ishimaru Y, Sakurai T, Yin L, Pan W, Ishiguro M, Masuda K, Abe K, Misaka T, Hirai H. Amino acid residues of bitter taste receptor TAS2R16 that determine sensitivity in primates to β-glycosides. Biophys Physicobiol 2016; 13:165-171. [PMID: 27924271 PMCID: PMC5042178 DOI: 10.2142/biophysico.13.0_165] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 03/02/2016] [Indexed: 12/01/2022] Open
Abstract
In mammals, bitter taste is mediated by TAS2Rs, which belong to the family of seven transmembrane G protein-coupled receptors. Since TAS2Rs are directly involved in the interaction between mammals and their dietary sources, it is likely that these genes evolved to reflect species-specific diets during mammalian evolution. Here, we analyzed the amino acids responsible for the difference in sensitivities of TAS2R16s of various primates using a cultured cell expression system. We found that the sensitivity of TAS2R16 varied due to several amino acid residues. Mutation of amino acid residues at E86T, L247M, and V260F in human and langur TAS2R16 for mimicking the macaque TAS2R16 decreased the sensitivity of the receptor in an additive manner, which suggests its contribution to the potency of salicin, possibly via direct interaction. However, mutation of amino acid residues 125 and 133 in human TAS2R16, which are situated in helix 4, to the macaque sequence increased the sensitivity of the receptor. These results suggest the possibility that bitter taste sensitivities evolved independently by replacing specific amino acid residues of TAS2Rs in different primate species to adapt to species-specific food.
Collapse
Affiliation(s)
- Hiroo Imai
- Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan
| | - Nami Suzuki-Hashido
- Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan
| | - Yoshiro Ishimaru
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Takanobu Sakurai
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Lijie Yin
- Center for Nature and Society, School of Life Sciences, Peking University, Beijing 100871, China
| | - Wenshi Pan
- Center for Nature and Society, School of Life Sciences, Peking University, Beijing 100871, China
| | - Masaji Ishiguro
- Department of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata 956-8603, Japan
| | - Katsuyoshi Masuda
- Suntory Institute for Bioorganic Research, Mishima-gun, Osaka 618-8503, Japan
| | - Keiko Abe
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Takumi Misaka
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
| | - Hirohisa Hirai
- Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan
| |
Collapse
|
13
|
Lyte M, Fodor AA, Chapman CD, Martin GG, Perez-Chanona E, Jobin C, Dess NK. Gut Microbiota and a Selectively Bred Taste Phenotype: A Novel Model of Microbiome-Behavior Relationships. Psychosom Med 2016; 78:610-9. [PMID: 27035357 DOI: 10.1097/psy.0000000000000318] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVES The microbiota-gut-brain axis is increasingly implicated in obesity, anxiety, stress, and other health-related processes. Researchers have proposed that gut microbiota may influence dietary habits, and pathways through the microbiota-gut-brain axis make such a relationship feasible; however, few data bear on the hypothesis. As a first step in the development of a model system, the gut microbiome was examined in rat lines selectively outbred on a taste phenotype with biobehavioral profiles that have diverged with respect to energy regulation, anxiety, and stress. METHODS Occidental low and high-saccharin-consuming rats were assessed for body mass and chow, water, and saccharin intake; littermate controls had shared cages with rats in the experimental group but were not assessed. Cecum and colon microbial communities were profiled using Illumina 16S rRNA sequencing and multivariate analysis of microbial diversity and composition. RESULTS The saccharin phenotype was confirmed (low-saccharin-consuming rats, 0.7Δ% [0.9Δ%]; high-saccharin-consuming rats, 28.1Δ% [3.6Δ%]). Regardless of saccharin exposure, gut microbiota differed between lines in terms of overall community similarity and taxa at lower phylogenetic levels. Specifically, 16 genera in three phyla distinguished the lines at a 10% false discovery rate. DISCUSSION The study demonstrates for the first time that rodent lines created through selective pressure on taste and differing on functionally related correlates host different microbial communities. Whether the microbiota are causally related to the taste phenotype or its correlates remains to be determined. These findings encourage further inquiry on the relationship of the microbiome to taste, dietary habits, emotion, and health.
Collapse
Affiliation(s)
- Mark Lyte
- From the Department of Veterinary Microbiology and Preventive Medicine, School of Veterinary Medicine (Lyte), Iowa State University, Ames, Iowa; Department of Immunotherapeutics and Biotechnology (Lyte), Texas Tech University Health Sciences Center, Abilene, Texas; Department of Bioinformatics and Genomics (Fodor), University of North Carolina at Charlotte, North Carolina; School of Medicine (Perez-Chanona), University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Division of Gastroenterology, Department of Medicine (Jobin), University of Florida College of Medicine, Gainesville, Florida; and Occidental College (Chapman, Martin, Dess), Los Angeles, California
| | | | | | | | | | | | | |
Collapse
|
14
|
Zhao F, Zhang T, Xie J, Zhang S, Nevo E, Su J, Lin G. Genetic variation in bitter taste receptor genes influences the foraging behavior of plateau zokor (Eospalax baileyi). Ecol Evol 2016; 6:2359-67. [PMID: 27110349 PMCID: PMC4834321 DOI: 10.1002/ece3.2041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 01/29/2016] [Accepted: 02/09/2016] [Indexed: 12/20/2022] Open
Abstract
The ability to detect bitter tastes is important for animals; it can help them to avoid ingesting harmful substances. Bitter taste perception is mainly mediated by bitter taste receptor proteins, which are encoded by members of the Tas2r gene family and vary with the dietary preference of a specific species. Although individuals with different genotypes differ in bitterness recognition capability, little is known about the relationship between genetic variation and food selection tendencies at the intraspecific level. In this study, we examined the relationship between genotypes and diet in plateau zokor (Eospalax baileyi), a subterranean rodent endemic to the Qinghai‐Tibet Plateau that caches food for the winter. We assayed the composition and taste profile of each plant contained in temporary caches and vicinity quadrats, which were representative of selected and available food, respectively. Bitter plant selection indices (Ebitter) were estimated. We also sequenced 26 candidate Tas2r genes from zokors and determined their relationships with the Ebitter of their caches. We identified four key results: (1) zokors varied considerably in both bitter food preference and Tas2r sequences; (2) five genes (zTas2r115,zTas2r119,zTas2r126,zTas2r134, and zTas2r136) exhibited allelic variation that was significantly associated with Ebitter; (3) synonymous SNPs, nonsynonymous SNPs, and pseudogenization are involved in the genotype–phenotype relationship; (4) the minor genotypes of zTas2r115,zTas2r134, and zTas2r136 and the major genotypes of zTas2r119 and zTas2r126 cached more bitter plants. Our results link Tas2r variation with food selection behavior at the population level for the first time.
Collapse
Affiliation(s)
- Fang Zhao
- Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China; University of Chinese Academy of Sciences Beijing 100049 China
| | - Tongzuo Zhang
- Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China
| | - Jiuxiang Xie
- Department of Grass Science Qinghai University Xining Qinghai 810016 China
| | - Shoudong Zhang
- Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China
| | - Eviatar Nevo
- Institute of Evolution University of Haifa Haifa 3498838 Israel
| | - Jianping Su
- Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China
| | - Gonghua Lin
- Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China
| |
Collapse
|
15
|
Richter I, Fidler AE. Marine invertebrate xenobiotic-activated nuclear receptors: their application as sensor elements in high-throughput bioassays for marine bioactive compounds. Mar Drugs 2014; 12:5590-618. [PMID: 25421319 PMCID: PMC4245547 DOI: 10.3390/md12115590] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 10/31/2014] [Accepted: 11/11/2014] [Indexed: 02/07/2023] Open
Abstract
Developing high-throughput assays to screen marine extracts for bioactive compounds presents both conceptual and technical challenges. One major challenge is to develop assays that have well-grounded ecological and evolutionary rationales. In this review we propose that a specific group of ligand-activated transcription factors are particularly well-suited to act as sensors in such bioassays. More specifically, xenobiotic-activated nuclear receptors (XANRs) regulate transcription of genes involved in xenobiotic detoxification. XANR ligand-binding domains (LBDs) may adaptively evolve to bind those bioactive, and potentially toxic, compounds to which organisms are normally exposed to through their specific diets. A brief overview of the function and taxonomic distribution of both vertebrate and invertebrate XANRs is first provided. Proof-of-concept experiments are then described which confirm that a filter-feeding marine invertebrate XANR LBD is activated by marine bioactive compounds. We speculate that increasing access to marine invertebrate genome sequence data, in combination with the expression of functional recombinant marine invertebrate XANR LBDs, will facilitate the generation of high-throughput bioassays/biosensors of widely differing specificities, but all based on activation of XANR LBDs. Such assays may find application in screening marine extracts for bioactive compounds that could act as drug lead compounds.
Collapse
Affiliation(s)
- Ingrid Richter
- Environmental Technology Group, Cawthron Institute, Private Bag 2, Nelson 7012, New Zealand.
| | - Andrew E Fidler
- Environmental Technology Group, Cawthron Institute, Private Bag 2, Nelson 7012, New Zealand.
| |
Collapse
|
16
|
Syed AS, Korsching SI. Positive Darwinian selection in the singularly large taste receptor gene family of an 'ancient' fish, Latimeria chalumnae. BMC Genomics 2014; 15:650. [PMID: 25091523 PMCID: PMC4132921 DOI: 10.1186/1471-2164-15-650] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 07/29/2014] [Indexed: 11/11/2022] Open
Abstract
Background Chemical senses are one of the foremost means by which organisms make sense of their environment, among them the olfactory and gustatory sense of vertebrates and arthropods. Both senses use large repertoires of receptors to achieve perception of complex chemosensory stimuli. High evolutionary dynamics of some olfactory and gustatory receptor gene families result in considerable variance of chemosensory perception between species. Interestingly, both ora/v1r genes and the closely related t2r genes constitute small and rather conserved families in teleost fish, but show rapid evolution and large species differences in tetrapods. To understand this transition, chemosensory gene repertoires of earlier diverging members of the tetrapod lineage, i.e. lobe-finned fish such as Latimeria would be of high interest. Results We report here the complete T2R repertoire of Latimeria chalumnae, using thorough data mining and extensive phylogenetic analysis. Eighty t2r genes were identified, by far the largest family reported for any species so far. The genomic neighborhood of t2r genes is enriched in repeat elements, which may have facilitated the extensive gene duplication events resulting in such a large family. Examination of non-synonymous vs. synonymous substitution rates (dN/dS) suggests pronounced positive Darwinian selection in Latimeria T2Rs, conceivably ensuring efficient neo-functionalization of newly born t2r genes. Notably, both traits, positive selection and enrichment of repeat elements in the genomic neighborhood, are absent in the twenty v1r genes of Latimeria. Sequence divergence in Latimeria T2Rs and V1Rs is high, reminescent of the corresponding teleost families. Some conserved sequence motifs of Latimeria T2Rs and V1Rs are shared with the respective teleost but not tetrapod genes, consistent with a potential role of such motifs in detection of aquatic chemosensory stimuli. Conclusions The singularly large T2R repertoire of Latimeria may have been generated by facilitating local gene duplication via increased density of repeat elements, and efficient neofunctionalization via positive Darwinian selection. The high evolutionary dynamics of tetrapod t2r gene families precedes the emergence of tetrapods, i.e. the water-to-land transition, and thus constitutes a basal feature of the lobe-finned lineage of vertebrates. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-650) contains supplementary material, which is available to authorized users.
Collapse
|
17
|
Hayakawa T, Suzuki-Hashido N, Matsui A, Go Y. Frequent Expansions of the Bitter Taste Receptor Gene Repertoire during Evolution of Mammals in the Euarchontoglires Clade. Mol Biol Evol 2014; 31:2018-31. [DOI: 10.1093/molbev/msu144] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
18
|
Ji M, Su X, Su X, Chen Y, Huang W, Zhang J, Gao Z, Li C, Lu X. Identification of novel compounds for human bitter taste receptors. Chem Biol Drug Des 2014; 84:63-74. [PMID: 24472524 DOI: 10.1111/cbdd.12293] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/06/2014] [Accepted: 01/15/2014] [Indexed: 01/28/2023]
Abstract
The finely tuned bitter taste sensing in humans is orchestrated by a group of 25 bitter taste receptors (TAS2Rs), which belong to the G-protein-coupled receptor superfamily. TAS2Rs are expressed in the specialized taste bud cells of the gustatory system and perceive a plethora of bitter substances with versatile structures. To date, more than one hundred bitter ligands have been matched with their cognate receptors, but the understanding of the molecular mechanisms of TAS2Rs remains limited. Additionally, the extraoral expression of TAS2R genes was found in the gastrointestinal tract and respiratory system, which suggests other important physiological functions for TAS2Rs. To gain insight into the physiological functions of TAS2Rs, we established a heterologous expression system and characterized the response of 24 TAS2Rs against a library of potential bitter compounds. Among these bitter compounds of interest, 18 bitter compounds activated 16 TAS2Rs, representing 42 tastant-receptor pairs. We then calculated 14 descriptor properties for the 18 positive compounds. By comparison with 102 previously annotated bitter compounds in the database, we discovered common descriptor properties that may contribute to the discovery of additional bitter ligands and further expand the known molecular receptive ranges of human TAS2Rs.
Collapse
Affiliation(s)
- Mingfei Ji
- Department of Urology, The Second Affiliated Hospital of Dalian Medical University, Dalian, 116023, China
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Li D, Zhang J. Diet shapes the evolution of the vertebrate bitter taste receptor gene repertoire. Mol Biol Evol 2013; 31:303-9. [PMID: 24202612 DOI: 10.1093/molbev/mst219] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Vertebrate Tas2r taste receptors bind to bitter compounds, which are typically poisonous, to elicit bitter sensation to prevent the ingestion of toxins. Previous studies noted a marked variation in the number of Tas2r genes among species, but the underlying cause is unclear. To address this question, we compile the Tas2r gene repertoires from 41 mammals, 4 birds, 2 reptiles, 1 amphibian, and 6 fishes. The number of intact Tas2r genes varies from 0 in the bottlenose dolphin to 51 in the Western clawed frog, with numerous expansions and contractions of the gene family throughout vertebrates, especially among tetrapods. The Tas2r gene number in a species correlates with the fraction of plants in its diet. Because plant tissues contain more toxic compounds than animal tissues do, our observation supports the hypothesis that dietary toxins are a major selective force shaping the diversity of the Tas2r repertoire.
Collapse
Affiliation(s)
- Diyan Li
- College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, Sichuan, China
| | | |
Collapse
|
20
|
Ledda M, Kutalik Z, Souza Destito MC, Souza MM, Cirillo CA, Zamboni A, Martin N, Morya E, Sameshima K, Beckmann JS, le Coutre J, Bergmann S, Genick UK. GWAS of human bitter taste perception identifies new loci and reveals additional complexity of bitter taste genetics. Hum Mol Genet 2013; 23:259-67. [PMID: 23966204 PMCID: PMC3857948 DOI: 10.1093/hmg/ddt404] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Human perception of bitterness displays pronounced interindividual variation. This phenotypic variation is mirrored by equally pronounced genetic variation in the family of bitter taste receptor genes. To better understand the effects of common genetic variations on human bitter taste perception, we conducted a genome-wide association study on a discovery panel of 504 subjects and a validation panel of 104 subjects from the general population of São Paulo in Brazil. Correction for general taste-sensitivity allowed us to identify a SNP in the cluster of bitter taste receptors on chr12 (10.88– 11.24 Mb, build 36.1) significantly associated (best SNP: rs2708377, P = 5.31 × 10−13, r2 = 8.9%, β = −0.12, s.e. = 0.016) with the perceived bitterness of caffeine. This association overlaps with—but is statistically distinct from—the previously identified SNP rs10772420 influencing the perception of quinine bitterness that falls in the same bitter taste cluster. We replicated this association to quinine perception (P = 4.97 × 10−37, r2 = 23.2%, β = 0.25, s.e. = 0.020) and additionally found the effect of this genetic locus to be concentration specific with a strong impact on the perception of low, but no impact on the perception of high concentrations of quinine. Our study, thus, furthers our understanding of the complex genetic architecture of bitter taste perception.
Collapse
Affiliation(s)
- Mirko Ledda
- Department of Food-Consumer Interaction, Nestlé Research Center, Lausanne, Switzerland
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
Genetic studies on taste sensitivity, and bitter taste receptors (T2R) in particular, are an essential tool to understand ingestive behavior and its relation to variations of nutritional status occurring in ruminants. In the present study, we conducted a data-mining search to identify T2R candidates in sheep by comparison with the described T2R in cattle and using recently available ovine genome. In sheep, we identified eight orthologs of cattle genes: T2R16, T2R10B, T2R12, T2R3, T2R4, T2R67, T2R13 and T2R5. The in silico predicted genes were then confirmed by PCR and DNA sequencing. The sequencing results showed a 99% to 100% similarity with the in silico predicted sequence. Moreover, we address the chromosomal distribution and compare, in homology and phylogenetic terms, the obtained genes with the known T2R in human, mouse, dog, cattle, horse and pig. The eight novel genes identified map either to ovine chromosome 3 or 4. The phylogenetic data suggest a clustering by receptor type rather than by species for some of the receptors. From the species analyzed, we observed a clear proximity between the two ruminant species, sheep and cattle, in contrast with lower similarities obtained for the comparison of sheep with other mammals. Although further studies are needed to identify the complete T2R repertoire in domestic sheep, our data represent a first step for genetic studies on this field.
Collapse
|
22
|
Sekine H, Takao K, Yoshinaga K, Kokubun S, Ikeda M. Effects of zinc deficiency and supplementation on gene expression of bitter taste receptors (TAS2Rs) on the tongue in rats. Laryngoscope 2012; 122:2411-7. [DOI: 10.1002/lary.23378] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 03/27/2012] [Accepted: 03/30/2012] [Indexed: 11/10/2022]
|
23
|
Hayakawa T, Sugawara T, Go Y, Udono T, Hirai H, Imai H. Eco-geographical diversification of bitter taste receptor genes (TAS2Rs) among subspecies of chimpanzees (Pan troglodytes). PLoS One 2012; 7:e43277. [PMID: 22916235 PMCID: PMC3420883 DOI: 10.1371/journal.pone.0043277] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 07/18/2012] [Indexed: 12/03/2022] Open
Abstract
Chimpanzees (Pan troglodytes) have region-specific difference in dietary repertoires from East to West across tropical Africa. Such differences may result from different genetic backgrounds in addition to cultural variations. We analyzed the sequences of all bitter taste receptor genes (cTAS2Rs) in a total of 59 chimpanzees, including 4 putative subspecies. We identified genetic variations including single-nucleotide variations (SNVs), insertions and deletions (indels), gene-conversion variations, and copy-number variations (CNVs) in cTAS2Rs. Approximately two-thirds of all cTAS2R haplotypes in the amino acid sequence were unique to each subspecies. We analyzed the evolutionary backgrounds of natural selection behind such diversification. Our previous study concluded that diversification of cTAS2Rs in western chimpanzees (P. t. verus) may have resulted from balancing selection. In contrast, the present study found that purifying selection dominates as the evolutionary form of diversification of the so-called human cluster of cTAS2Rs in eastern chimpanzees (P. t. schweinfurthii) and that the other cTAS2Rs were under no obvious selection as a whole. Such marked diversification of cTAS2Rs with different evolutionary backgrounds among subspecies of chimpanzees probably reflects their subspecies-specific dietary repertoires.
Collapse
Affiliation(s)
- Takashi Hayakawa
- Molecular Biology Section, Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
- Japan Society for Promotion of Science, Tokyo, Japan
| | - Tohru Sugawara
- Molecular Biology Section, Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Yasuhiro Go
- Molecular Biology Section, Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Toshifumi Udono
- Kumamoto Sanctuary, Wildlife Research Center of Kyoto University, Uki, Kumamoto, Japan
| | - Hirohisa Hirai
- Molecular Biology Section, Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Hiroo Imai
- Molecular Biology Section, Department of Cellular and Molecular Biology, Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| |
Collapse
|
24
|
Imai H, Suzuki N, Ishimaru Y, Sakurai T, Yin L, Pan W, Abe K, Misaka T, Hirai H. Functional diversity of bitter taste receptor TAS2R16 in primates. Biol Lett 2012; 8:652-6. [PMID: 22399783 DOI: 10.1098/rsbl.2011.1251] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In mammals, bitter taste is mediated by TAS2R genes, which belong to the large family of seven transmembrane G protein-coupled receptors. Because TAS2Rs are directly involved in the interaction between mammals and their dietary sources, it is likely that these genes evolved to reflect species-specific diets during mammalian evolution. Here, we investigated the sensitivities of TAS2R16s of various primates by using a cultured cell expression system, and found that the sensitivity of each primate species varied according to the ligand. Especially, the sensitivity of TAS2R16 of Japanese macaques to salicin was much lower than that of human TAS2R16, which was supported by behavioural tests. These results suggest the possibility that bitter-taste sensitivities evolved independently by replacing specific amino acid residues of TAS2Rs in different primate species to adapt to food items they use.
Collapse
Affiliation(s)
- Hiroo Imai
- Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|