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1.
Sci Rep ; 9(1): 10400, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320702

RESUMO

The α-carbonic anhydrases (α-CAs) are a large and ancient group of metazoan-specific enzymes. They generate bicarbonate from metabolic carbon dioxide and through calcium carbonate crystal formation play a key role in the regulation of mineralized structures. To better understand how α-CAs contribute to shell mineralization in the marine Mediterranean mussel (Mytilus galloprovincialis) we characterized them in the mantle. Phylogenetic analysis revealed that mollusc α-CA evolution was affected by lineage and species-specific events. Ten α-CAs were found in the Mediterranean mussel mantle and the most abundant form was named, MgNACR, as it grouped with oyster nacreins (NACR). Exposure of the Mediterranean mussel to reduced water salinity (18 vs 37 ppt), caused a significant reduction (p < 0.05) in mantle esterase activity and MgNACR transcript abundance (p < 0.05). Protonograms revealed multiple proteins in the mantle with α-CA hydratase activity and mapped to a protein with a similar size to that deduced for monomeric MgNACR. Our data indicate that MgNACR is a major α-CA enzyme in mantle and that by homology with oyster nacreins likely regulates mussel shell production. We propose that species-dependent α-CA evolution may contribute to explain the diversity of bivalve shell structures and their vulnerability to environmental changes.

2.
Fish Shellfish Immunol ; 90: 134-140, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31055019

RESUMO

Toll-like receptors (TLRs) are a large family of pattern recognition receptors (PRRs) that play a critical role in innate immunity. TLRs are activated when they recognize microbial associated molecular patterns (MAMPs) of bacteria, viruses, or fungus. In the present study, two TLRs were isolated from the mantle of the hard-shelled mussel (Mytilus coruscus) and designated McTLR2 and McTLR3 based on their sequence similarity and phylogenetic clustering with Crassostrea gigas, CgiTLR2 and CgiTLR3, respectively. Quantitative RT-PCR analysis demonstrated that McTLR2 and McTLR3 were constitutively expressed in many tissues but at low abundance.


Assuntos
Hemócitos/imunologia , Imunidade Inata/genética , Mytilus/genética , Mytilus/imunologia , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Sequência de Aminoácidos , Animais , Perfilação da Expressão Gênica , Hemócitos/metabolismo , Filogenia , Alinhamento de Sequência , Receptores Toll-Like/química
3.
Sci Rep ; 8(1): 17807, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30546023

RESUMO

Mosquito breeding depends on the supply of fresh vertebrate blood, a major bottleneck for large-scale production of Anopheles spp. Feeding alternatives to fresh blood are thus a priority for research, outdoor large-cage trials and control interventions. Several artificial meal compositions were tested and Anopheles oogenesis, egg laying and development into the next generation of adult mosquitoes were followed. We identified blood-substitute-diets that supported ovarian development, egg maturation and fertility as well as, low progeny larval mortality, and normal development of offspring into adult mosquitoes. The formulated diet is an effective artificial meal, free of fresh blood that mimics a vertebrate blood meal and represents an important advance for the sustainability of Anopheles mosquito rearing in captivity.


Assuntos
Ração Animal , Anopheles/crescimento & desenvolvimento , Comportamento Alimentar , Mosquitos Vetores/crescimento & desenvolvimento , Animais , Feminino , Humanos , Masculino
4.
Sci Rep ; 8(1): 6027, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-29662086

RESUMO

The ATP-binding cassette transporter 6 (ABCC6) gene encodes a cellular transmembrane protein transporter (MRP6) that is involved in the regulation of tissue calcification in mammals. Mutations in ABCC6 are associated with human ectopic calcification disorders. To gain insight into its evolution and involvement in tissue calcification we conducted a comparative analysis of the ABCC6 gene and the related gene ABCC1 from invertebrates to vertebrates where a bony endoskeleton first evolved. Taking into consideration the role of ABCC6 in ectopic calcification of human skin we analysed the involvement of both genes in the regeneration of scales, mineralized structures that develop in fish skin. The ABCC6 gene was only found in bony vertebrate genomes and was absent from Elasmobranchs, Agnatha and from invertebrates. In teleost fish the abcc6 gene duplicated but the two genes persisted only in some teleost genomes. Six disease causing amino acid mutations in human MRP6 are a normal feature of abcc6 in fish, suggesting they do not have a deleterious effect on the protein. After scale removal the abcc6 (5 and 10 days) and abcc1 (10 days) gene expression was up-regulated relative to the intact control skin and this coincided with a time of intense scale mineralization.

5.
Gen Comp Endocrinol ; 264: 113-130, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29056448

RESUMO

In fishes, including the jawless lampreys, the most ancient lineage of extant vertebrates, plasma glucose levels are highly variable and regulation is more relaxed than in mammals. The regulation of glucose and lipid in fishes in common with mammals involves members of the glucagon (GCG)-like family of gastrointestinal peptides. In mammals, four peptides GCG, glucagon-like peptide 1 and 2 (GLP1 and GLP2) and glucose-dependent insulinotropic peptide (GIP) that activate four specific receptors exist. However, in lamprey and other fishes the glucagon-like family evolved differently and they retained additional gene family members (glucagon-related peptide, gcrp and its receptor, gcrpr) that are absent from mammals. In the present study, we analysed the evolution of the glucagon-like system in fish and characterized gene expression of the family members in the European sea bass (Dicentrarchus labrax) a teleost fish. Phylogenetic analysis revealed that multiple receptors and peptides of the glucagon-like family emerged early during the vertebrate radiation and evolved via lineage specific events. Synteny analysis suggested that family member gene loss is likely to be the result of a single gene deletion event. Lamprey was the only fish where a putative glp1r persisted and the presence of the receptor gene in the genomes of the elephant shark and coelacanth remains unresolved. In the coelacanth and elephant shark, unique proglucagon genes were acquired which in the former only encoded Gcg and Glp2 and in the latter, shared a similar structure to the teleost proglucagon gene but possessed an extra exon coding for Glp-like peptide that was most similar to Glp2. The variable tissue distribution of the gene transcripts encoding the ligands and receptors of the glucagon-like system in an advanced teleost, the European sea bass, suggested that, as occurs in mammals, they have acquired distinct functions. Statistically significant (p < .05) down-regulation of teleost proglucagon a in sea bass with modified plasma glucose levels confirmed the link between these peptides and metabolism. The tissue distribution of members of the glucagon-like system in sea bass and human suggests that evolution of the brain-gut-peptide regulatory loop diverged between teleosts and mammals despite the overall conservation and similarity of glucagon-like family members.


Assuntos
Evolução Molecular , Peixes/genética , Glucagon/genética , Sequência de Aminoácidos , Animais , Perfilação da Expressão Gênica , Genoma , Glucagon/química , Humanos , Peptídeos/genética , Filogenia , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética , Sintenia/genética
6.
J Plant Physiol ; 218: 35-44, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28763707

RESUMO

The essential oil of Thymus albicans Hoffmanns. & Link, a native shrub from the Iberian Peninsula, is mainly composed of monoterpenes. In this study, a 1,8-cineole synthase was isolated from the 1,8-cineole chemotype. A partial sequence that lacked the complete plastid transit peptide but contained an extended C-terminal when compared to other related terpene synthases was generated by PCR and Rapid Amplification of cDNA Ends (RACE). The predicted mature polypeptide was 593 amino acids in length and shared 78% and 77% sequence similarity with the homologue 1,8-cineole synthase from Rosmarinus officinalis and Salvia officinalis, respectively. The putative protein possessed the characteristic conserved motifs of plant monoterpene synthases including the RRx8W and DDxxD motifs and phylogenetic analysis indicated that the amplified 1,8-cineole synthase bears greater sequence similarity with other 1,8-cineole synthases from Lamiaceae family relative to the terpene synthases from the genus Thymus. Functional expression of the recombinant protein in Escherichia coli revealed that in the presence of geranyl diphosphate (GPP) 1,8-cineole was the major product but that its production was too low for robust quantification. Other minor conversion products included α-pinene, ß-pinene, sabinene and ß-myrcene suggesting the isolated 1,8-cineole synthase may be a multi-product enzyme. To our knowledge, this is the first report of a functionally characterized monoterpene synthase from Thymus albicans.


Assuntos
Evolução Molecular , Liases Intramoleculares/genética , Proteínas de Plantas/genética , Thymus (Planta)/genética , Sequência de Aminoácidos , Escherichia coli/genética , Liases Intramoleculares/química , Liases Intramoleculares/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Thymus (Planta)/metabolismo
7.
J Endocrinol ; 233(3): 381-394, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28420709

RESUMO

The impact of thermal imprinting on the plasticity of the hypothalamic-pituitary-interrenal (HPI) axis and stress response in an adult ectotherm, the gilthead sea bream (Sparusaurata, L.), during its development was assessed. Fish were reared under 4 thermal regimes, and the resulting adults exposed to acute confinement stress and plasma cortisol levels and genes of the HPI axis were monitored. Changes in immune function, a common result of stress, were also evaluated using histomorphometric measurements of melanomacrophages centers (MMCs) in the head kidney and by monitoring macrophage-related transcripts. Thermal history significantly modified the HPI responsiveness in adult sea bream when eggs and larvae were reared at a higher than optimal temperature (HT, 22°C), and they had a reduced amplitude in their cortisol response and significantly upregulated pituitary pomc and head kidney star transcripts. Additionally, after an acute stress challenge, immune function was modified and the head kidney of adult fish reared during development at high temperatures (HT and LHT, 18-22°C) had a decreased number of MMCs and a significant downregulation of dopachrome tautomerase. Thermal imprinting during development influenced adult sea bream physiology and increased plasma levels of glucose and sodium even in the absence of an acute stress in fish reared under a high-low thermal regime (HLT, 22-18°C). Overall, the results demonstrate that temperature during early development influences the adult HPI axis and immune function in a teleost fish.


Assuntos
Temperatura Alta , Imunidade Inata/fisiologia , Dourada/imunologia , Estresse Fisiológico/imunologia , Animais , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/imunologia , Glândula Inter-Renal/imunologia , Dourada/sangue
8.
BMC Evol Biol ; 17(1): 14, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086749

RESUMO

BACKGROUND: The skin in vertebrates is a protective barrier and damage is rapidly repaired to re-establish barrier function and maintain internal homeostasis. The angiopoietin-like (ANGPTL) proteins are a family of eight secreted glycoproteins with an important role in skin repair and angiogenesis in humans. In other vertebrates their existence and role in skin remains largely unstudied. The present study characterizes for the first time the homologues of human ANGPTLs in fish and identifies the candidates that share a conserved role in skin repair using a regenerating teleost skin model over a 4-day healing period. RESULTS: Homologues of human ANGPTL1-7 were identified in fish, although ANGPTL8 was absent and a totally new family member designated angptl9 was identified in fish and other non-mammalian vertebrates. In the teleost fishes a gene family expansion occurred but all the deduced Angptl proteins retained conserved sequence and structure motifs with the human homologues. In sea bream skin angptl1b, angptl2b, angptl4a, angptl4b and angptl7 transcripts were successfully amplified and they were differentially expressed during skin regeneration. In the first 2 days of skin regeneration, re-establishment of the physical barrier and an increase in the number of blood vessels was observed. During the initial stages of skin regeneration angptl1b and angptl2b transcripts were significantly more abundant (p < 0.05) than in intact skin and angptl7 transcripts were down-regulated (p < 0.05) throughout the 4-days of skin regeneration that was studied. No difference in angptl4a and angptl4b transcript abundance was detected during regeneration or between regenerating and intact skin. CONCLUSIONS: The angptl gene family has expanded in teleost genomes. In sea bream, changes in the expression of angptl1b, angptl2b and angptl7 were correlated with the main phases of skin regeneration, indicating the involvement of ANGPTL family members in skin regeneration has been conserved in the vertebrates. Exploration of the fish angptl family in skin sheds new light on the understanding of the molecular basis of skin regeneration an issue of importance for disease control in aquaculture.


Assuntos
Angiopoietinas/genética , Evolução Molecular , Peixes/genética , Regeneração , Fenômenos Fisiológicos da Pele , Animais , Sequência Conservada , Regulação para Baixo , Peixes/fisiologia , Humanos , Família Multigênica , Filogenia
9.
Proteins ; 85(2): 242-255, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27862299

RESUMO

Cartilage acidic protein1 (CRTAC1) is an extracellular matrix protein of chondrogenic tissue in humans and its presence in bacteria indicate it is of ancient origin. Structural modeling of piscine CRTAC1 reveals it belongs to the large family of beta-propeller proteins that in mammals have been associated with diseases, including amyloid diseases such as Alzheimer's. In order to characterize the structure/function evolution of this new member of the beta-propeller family we exploited the unique characteristics of piscine duplicate genes Crtac1a and Crtac1b and compared their structural and biochemical modifications with human recombinant CRTAC1. We demonstrate that CRTAC1 has a beta-propeller structure that has been conserved during evolution and easily forms high molecular weight thermo-stable aggregates. We reveal for the first time the propensity of CRTAC1 to form amyloid-like structures, and hypothesize that the aggregating property of CRTAC1 may be related to its disease-association. We further contribute to the general understating of CRTAC1's and beta-propeller family evolution and function. Proteins 2017; 85:242-255. © 2016 Wiley Periodicals, Inc.

10.
J Mol Endocrinol ; 57(1): 73-86, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27220618

RESUMO

The evolution of the peptide family consisting of corticotropin-releasing hormone (CRH) and the three urocortins (UCN1-3) has been puzzling due to uneven evolutionary rates. Distinct gene duplication scenarios have been proposed in relation to the two basal rounds of vertebrate genome doubling (2R) and the teleost fish-specific genome doubling (3R). By analyses of sequences and chromosomal regions, including many neighboring gene families, we show here that the vertebrate progenitor had two peptide genes that served as the founders of separate subfamilies. Then, 2R resulted in a total of five members: one subfamily consists of CRH1, CRH2, and UCN1. The other subfamily contains UCN2 and UCN3. All five peptide genes are present in the slowly evolving genomes of the coelacanth Latimeria chalumnae (a lobe-finned fish), the spotted gar Lepisosteus oculatus (a basal ray-finned fish), and the elephant shark Callorhinchus milii (a cartilaginous fish). The CRH2 gene has been lost independently in placental mammals and in teleost fish, but is present in birds (except chicken), anole lizard, and the nonplacental mammals platypus and opossum. Teleost 3R resulted in an additional surviving duplicate only for crh1 in some teleosts including zebrafish (crh1a and crh1b). We have previously reported that the two vertebrate CRH/UCN receptors arose in 2R and that CRHR1 was duplicated in 3R. Thus, we can now conclude that this peptide-receptor system was quite complex in the ancestor of the jawed vertebrates with five CRH/UCN peptides and two receptors, and that crh and crhr1 were duplicated in the teleost fish tetraploidization.


Assuntos
Hormônio Liberador da Corticotropina/genética , Evolução Molecular , Família Multigênica , Sequência de Aminoácidos , Animais , Biologia Computacional/métodos , Hormônio Liberador da Corticotropina/química , Hormônio Liberador da Corticotropina/classificação , Mineração de Dados , Bases de Dados Genéticas , Humanos , Mamíferos/classificação , Mamíferos/genética , Filogenia , Vertebrados/classificação , Vertebrados/genética
11.
Mar Genomics ; 27: 25-35, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26751715

RESUMO

Allatostatin-type A (AST-A), kisspeptin (KISS) and galanin (GAL) G-protein coupled receptor (GPCR) systems share a common ancestral origin in arthropods and the vertebrates where they regulate metabolism and reproduction. The molluscs are the second most diverse phylum in the animal kingdom, they occupy an important phylogenetic position, and their genome is more similar to deuterostomes than the arthropods and nematodes and thus they are good models for studies of gene family evolution and function. This mini-review intends to extend the current knowledge about AST-A, KISS and GAL GPCR system evolution and their putative function in the mollusc mantle. Comparative evolutionary analysis of the target GPCR systems was established by identifying homologues in genomes and tissue transcriptome datasets available for molluscs and comparing them to those of other metazoan systems. Studies in arthropods have revealed the existence of the AST-A system but the loss of homologues of the KISS and GAL systems. Homologues of the insect AST-AR and vertebrate KISSR genes were found in molluscs but putative GALR genes were absent. Receptor gene number suggested that members of this family have suffered lineage specific evolution during the molluscan radiation. In molluscs, orthologues of the insect AST-A peptides were not identified but buccalin peptides that are structurally related were identified and are putative receptor agonists. The identification of AST-AR and KISSR genes in molluscs strengthens the hypotheses that in metazoans members of the AST-AR subfamily share evolutionary proximity with KISSRs. The variable number of receptors and large repertoire of buccalin peptides may be indicative of the functional diversity of the AST-AR/KISSR systems in molluscs. The identification of AST-A and KISS receptors and ligands in the mantle transcriptome indicates that in molluscs they may have acquired a novel function and may play a role in shell development or sensory detection in the mantle.


Assuntos
Bivalves/genética , Evolução Molecular , Kisspeptinas/genética , Neuropeptídeos/genética , Receptores Acoplados a Proteínas-G/genética , Exoesqueleto/crescimento & desenvolvimento , Animais , Bivalves/crescimento & desenvolvimento , Bivalves/metabolismo , Calcificação Fisiológica , Galanina/genética , Galanina/metabolismo , Kisspeptinas/metabolismo , Ligantes , Neuropeptídeos/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo
12.
PLoS One ; 10(7): e0130347, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26135459

RESUMO

UNLABELLED: Allatostatin type A receptors (AST-ARs) are a group of G-protein coupled receptors activated by members of the FGL-amide (AST-A) peptide family that inhibit food intake and development in arthropods. Despite their physiological importance the evolution of the AST-A system is poorly described and relatively few receptors have been isolated and functionally characterised in insects. The present study provides a comprehensive analysis of the origin and comparative evolution of the AST-A system. To determine how evolution and feeding modified the function of AST-AR the duplicate receptors in Anopheles mosquitoes, were characterised. Phylogeny and gene synteny suggested that invertebrate AST-A receptors and peptide genes shared a common evolutionary origin with KISS/GAL receptors and ligands. AST-ARs and KISSR emerged from a common gene ancestor after the divergence of GALRs in the bilaterian genome. In arthropods, the AST-A system evolved through lineage-specific events and the maintenance of two receptors in the flies and mosquitoes (Diptera) was the result of a gene duplication event. Speciation of Anopheles mosquitoes affected receptor gene organisation and characterisation of AST-AR duplicates (GPRALS1 and 2) revealed that in common with other insects, the mosquito receptors were activated by insect AST-A peptides and the iCa2+-signalling pathway was stimulated. GPRALS1 and 2 were expressed mainly in mosquito midgut and ovaries and transcript abundance of both receptors was modified by feeding. A blood meal strongly up-regulated expression of both GPRALS in the midgut (p < 0.05) compared to glucose fed females. Based on the results we hypothesise that the AST-A system in insects shared a common origin with the vertebrate KISS system and may also share a common function as an integrator of metabolism and reproduction. HIGHLIGHTS: AST-A and KISS/GAL receptors and ligands shared common ancestry prior to the protostome-deuterostome divergence. Phylogeny and gene synteny revealed that AST-AR and KISSR emerged after GALR gene divergence. AST-AR genes were present in the hemichordates but were lost from the chordates. In protostomes, AST-ARs persisted and evolved through lineage-specific events and duplicated in the arthropod radiation. Diptera acquired and maintained functionally divergent duplicate AST-AR genes.


Assuntos
Anopheles/genética , Genoma de Inseto , Proteínas de Insetos/genética , Filogenia , Receptores Acoplados a Proteínas-G/genética , Receptores de Galanina/genética , Receptores de Neuropeptídeos/genética , Sequência de Aminoácidos , Animais , Anopheles/classificação , Anopheles/metabolismo , Sinalização do Cálcio , Evolução Molecular , Corpo Adiposo/química , Corpo Adiposo/metabolismo , Feminino , Expressão Gênica , Glucose/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/química , Camundongos , Dados de Sequência Molecular , Família Multigênica , Ovário/química , Ovário/metabolismo , Receptores Acoplados a Proteínas-G/química , Receptores Acoplados a Proteínas-G/metabolismo , Receptores de Galanina/química , Receptores de Galanina/metabolismo , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/metabolismo , Reprodução/genética , Alinhamento de Sequência , Sintenia
13.
Mol Cell Endocrinol ; 411: 130-45, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25933704

RESUMO

Pituitary adenylate cyclase-activating polypeptide (PACAP) administered to tilapia melanophores ex-vivo causes significant pigment aggregation and this is a newly identified function for this peptide in fish. The G-protein coupled receptors (GPCRs), adcyap1r1a (encoding Pac1a) and vipr2a (encoding Vpac2a), are the only receptors in melanophores with appreciable levels of expression and are significantly (p < 0.05) down-regulated in the absence of light. Vpac2a is activated exclusively by peptide histidine isoleucine (PHI), which suggests that Pac1a mediates the melanin aggregating effect of PACAP on melanophores. Paradoxically activation of Pac1a with PACAP caused a rise in cAMP, which in fish melanophores is associated with melanin dispersion. We hypothesise that the duplicate adcyap1ra and vipr2a genes in teleosts have acquired a specific role in skin and that the melanin aggregating effect of PACAP results from the interaction of Pac1a with Ramp that attenuates cAMP-dependent PKA activity and favours the Ca(2+)/Calmodulin dependent pathway.


Assuntos
Melanóforos/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Pele/metabolismo , Animais , Evolução Biológica , Bases de Dados Factuais , Filogenia , Tilápia
15.
Gen Comp Endocrinol ; 209: 162-70, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25230393

RESUMO

The corticotropin releasing hormone receptors (CRHR) and the arthropod diuretic hormone 44 receptors (DH44R) are structurally and functionally related members of the G protein-coupled receptors (GPCR) of the secretin-like receptor superfamily. We show here that they derive from a bilaterian predecessor. In protostomes, the receptor became DH44R that has been identified and functionally characterised in several arthropods but the gene seems to be absent from nematode genomes. Duplicate DH44R genes (DH44 R1 and DH44R2) have been described in some arthropods resulting from lineage-specific duplications. Recently, CRHR-DH44R-like receptors have been identified in the genomes of some lophotrochozoans (molluscs, which have a lineage-specific gene duplication, and annelids) as well as representatives of early diverging deuterostomes. Vertebrates have previously been reported to have two CRHR receptors that were named CRHR1 and CRHR2. To resolve their origin we have analysed recently assembled genomes from representatives of early vertebrate divergencies including elephant shark, spotted gar and coelacanth. We show here by analysis of synteny conservation that the two CRHR genes arose from a common ancestral gene in the early vertebrate tetraploidizations (2R) approximately 500 million years ago. Subsequently, the teleost-specific tetraploidization (3R) resulted in a duplicate of CRHR1 that has been lost in some teleost lineages. These results help distinguish orthology and paralogy relationships and will allow studies of functional conservation and changes during evolution of the individual members of the receptor family and their multiple native peptide agonists.


Assuntos
Hormônio Liberador da Corticotropina/genética , Proteínas de Drosophila/genética , Evolução Molecular , Invertebrados/genética , Receptores de Superfície Celular/genética , Vertebrados/genética , Animais , Sequência Conservada , Hormônio Liberador da Corticotropina/classificação , Hormônio Liberador da Corticotropina/metabolismo , Proteínas de Drosophila/classificação , Proteínas de Drosophila/metabolismo , Humanos , Hormônios de Inseto/genética , Hormônios de Inseto/metabolismo , Invertebrados/metabolismo , Filogenia , Receptores de Superfície Celular/classificação , Receptores de Superfície Celular/metabolismo , Vertebrados/metabolismo
16.
Gen Comp Endocrinol ; 209: 82-92, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24906176

RESUMO

The secretin receptor (SCTR) is a member of Class 2 subfamily B1 GPCRs and part of the PAC1/VPAC receptor subfamily. This receptor has long been known in mammals but has only recently been identified in other vertebrates including teleosts, from which it was previously considered to be absent. The ligand for SCTR in mammals is secretin (SCT), an important gastrointestinal peptide, which in teleosts has not yet been isolated, or the gene identified. This study revises the evolutionary model previously proposed for the secretin-GPCRs in metazoan by analysing in detail the fishes, the most successful of the extant vertebrates. All the Actinopterygii genomes analysed and the Chondrichthyes and Sarcopterygii fish possess a SCTR gene that shares conserved sequence, structure and synteny with the tetrapod homologue. Phylogenetic clustering and gene environment comparisons revealed that fish and tetrapod SCTR shared a common origin and diverged early from the PAC1/VPAC subfamily group. In teleosts SCTR duplicated as a result of the fish specific whole genome duplication but in all the teleost genomes analysed, with the exception of tilapia (Oreochromis niloticus), one of the duplicates was lost. The function of SCTR in teleosts is unknown but quantitative PCR revealed that in both sea bass (Dicentrarchus labrax) and tilapia (Oreochromis mossambicus) transcript abundance is high in the gastrointestinal tract suggesting it may intervene in similar processes to those in mammals. In contrast, no gene encoding the ligand SCT was identified in the ray-finned fishes (Actinopterygii) although it was present in the coelacanth (lobe finned fish, Sarcopterygii) and in the elephant shark (holocephalian). The genes in linkage with SCT in tetrapods and coelacanth were also identified in ray-finned fishes supporting the idea that it was lost from their genome. At present SCTR remains an orphan receptor in ray-finned fishes and it will be of interest in the future to establish why SCT was lost and which ligand substitutes for it so that full characterization of the receptor can occur.


Assuntos
Evolução Molecular , Peixes/genética , Genoma , Receptores Acoplados a Proteínas-G/genética , Receptores dos Hormônios Gastrointestinais/genética , Secretina/genética , Sequência de Aminoácidos , Animais , Sequência Conservada/genética , Peixes/metabolismo , Dados de Sequência Molecular , Filogenia , Receptores Acoplados a Proteínas-G/classificação , Receptores dos Hormônios Gastrointestinais/classificação , Secretina/metabolismo , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
17.
PLoS One ; 9(3): e92220, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24651821

RESUMO

Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes.


Assuntos
Artrópodes/genética , Evolução Molecular , Genoma Helmíntico/genética , Genoma de Inseto/genética , Nematoides/genética , Receptores CCR10/genética , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/genética , Sequência Conservada/genética , Drosophila melanogaster/genética , Genes de Helmintos/genética , Genes de Insetos/genética , Ligação Genética , Loci Gênicos , Humanos , Modelos Genéticos , Dados de Sequência Molecular , Família Multigênica , Filogenia , Estrutura Terciária de Proteína , Receptores CCR10/química , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
18.
Biochimie ; 95(8): 1534-43, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23603114

RESUMO

Sequence homologues of the bacterium Streptomyces violaceoruber and sea anemone Nematostella vectensis PLA2 pfam09056 members were identified in several bacteria, fungi and metazoans illustrating the evolution of this PLA2 sub-family. Comparison of their molecular structures revealed that bacteria and fungi members are part of the GXIV of PLA2s while metazoan representatives are similar with GIX PLA2 of the marine snail Conus magus. Members of GXIV and GIX PLA2s show modest overall sequence similarity (21-35%) but considerable motif conservation within the putative Ca(2+)-binding, catalytic sites and cysteine residue positions which are essential for enzyme function. GXIV PLA2s of bacteria and fungi typically contain four cysteine residues composing two intramolecular disulphide bonds. GIX PLA2 homologues were identified in cnidarians and molluscs and in a single tunicate but appear to be absent from other metazoan genomes. The mature GIX PLA2 deduced peptides contain up to ten cysteine residues capable of forming five putative disulphide bonds. Three disulphide bonds were identified in GIX PLA2s, two of which correspond to those localized in GXIV PLA2s. Phylogenetic analysis demonstrates that metazoan GIX PLA2s cluster separate from the bacterial and fungal GXIV PLA2s and both pfam09056 members form a group separate from the prokaryote and eukaryote GXIIA PLA2 pfam06951. Duplicate PLA2 pfam09056 genes were identified in the genomes of sea anemone N. vectensis and oyster Crassostrea gigas suggest that members of this family evolved via species-specific duplication events. These observations indicate that the newly identified metazoan pfam09056 members may be classified as GIX PLA2s and support the idea of the common evolutionary origin of GXIV and GIX PLA2 pfam09056 members, which emerged early in bacteria and were maintained in the genomes of fungi and selected extant metazoan taxa.


Assuntos
Bactérias/genética , Evolução Molecular , Fungos/genética , Invertebrados/classificação , Invertebrados/genética , Fosfolipases A2 Secretórias/genética , Filogenia , Animais , Bactérias/química , Bactérias/enzimologia , Sequência Conservada , Fungos/química , Fungos/enzimologia , Invertebrados/enzimologia , Fosfolipases A2 Secretórias/química , Alinhamento de Sequência
19.
Artigo em Inglês | MEDLINE | ID: mdl-23264768

RESUMO

In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs) play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologs of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans), and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster), suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologs of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR) that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors.

20.
Artigo em Inglês | MEDLINE | ID: mdl-22909802

RESUMO

Vertebrate group XII phospholipases A(2) (GXII PLA(2), conserved domain pfam06951) are proteins with unique structural and functional features within the secreted PLA(2) family. In humans, two genes (GXIIA PLA(2) and GXIIB PLA(2)) have been characterised. GXIIA PLA(2) is enzymatically active whereas GXIIB PLA(2) is devoid of catalytic activity. Recently, putative homologues of the vertebrate GXII PLA(2)s were described in non-vertebrates. In the current study a total of 170 GXII PLA(2) sequences were identified in vertebrates, invertebrates, non-metazoan eukaryotes, fungi and bacteria. GXIIB PLA(2) was found only in vertebrates and the searches failed to identify putative GXII PLA(2) homologues in Archaea. Comparisons of the predicted functional domains of GXII PLA(2)s revealed considerable structural identity within the Ca(2+)-binding and the catalytic sites among the various organisms suggesting that functional conservation may have been retained across evolution. The preservation of GXII PLA(2) family members from bacteria to human indicates that they have emerged early in evolution and evolved via gene/genome duplication events prior to Eubacteria. Gene duplicates were identified in some invertebrate taxa suggesting that species-specific duplications occurred. The analysis of the GXII PLA(2) homologue genome environment revealed that gene synteny and gene order are preserved in vertebrates. Conservation of GXII PLA(2)s indicates that important functional roles involved in species survival and were maintained across evolution and may be dependent on or independent of the enzyme's phospholipolytic activity.


Assuntos
Bactérias/enzimologia , Sequência Conservada , Fosfolipases A2/metabolismo , Animais , Humanos
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