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1.
BMC Genomics ; 25(1): 339, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575860

RESUMO

BACKGROUND: Cetaceans, having experienced prolonged adaptation to aquatic environments, have undergone evolutionary changes in their respiratory systems. This process of evolution has resulted in the emergence of distinctive phenotypic traits, notably the abundance of elastic fibers and thickened alveolar walls in their lungs, which may facilitate alveolar collapse during diving. This structure helps selective exchange of oxygen and carbon dioxide, while minimizing nitrogen exchange, thereby reducing the risk of DCS. Nevertheless, the scientific inquiry into the mechanisms through which these unique phenotypic characteristics govern the diving behavior of marine mammals, including cetaceans, remains unresolved. RESULTS: This study entails an evolutionary analysis of 42 genes associated with pulmonary fibrosis across 45 mammalian species. Twenty-one genes in cetaceans exhibited accelerated evolution, featuring specific amino acid substitutions in 14 of them. Primarily linked to the development of the respiratory system and lung morphological construction, these genes play a crucial role. Moreover, among marine mammals, we identified eight genes undergoing positive selection, and the evolutionary rates of three genes significantly correlated with diving depth. Specifically, the SFTPC gene exhibited convergent amino acid substitutions. Through in vitro cellular experiments, we illustrated that convergent amino acid site mutations in SFTPC contribute positively to pulmonary fibrosis in marine mammals, and the presence of this phenotype can induce deep alveolar collapse during diving, thereby reducing the risk of DCS during diving. CONCLUSIONS: The study unveils pivotal genetic signals in cetaceans and other marine mammals, arising through evolution. These genetic signals may influence lung characteristics in marine mammals and have been linked to a reduced risk of developing DCS. Moreover, the research serves as a valuable reference for delving deeper into human diving physiology.


Assuntos
Fibrose Pulmonar , Animais , Humanos , Cetáceos/genética , Cetáceos/metabolismo , Pulmão/metabolismo , Mamíferos/metabolismo , Oxigênio/metabolismo
2.
Eur J Neurosci ; 59(10): 2616-2627, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38441250

RESUMO

Parkinson's disease (PD) is an age-related progressive neurodegenerative disorder characterized by both motor and non-motor symptoms resulting from the death of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and noradrenergic neurons in the locus coeruleus (LC). The current diagnosis of PD primarily relies on motor symptoms, often leading to diagnoses in advanced stages, where a significant portion of SNpc dopamine neurons has already succumbed. Therefore, the identification of imaging biomarkers for early-stage PD diagnosis and disease progression monitoring is imperative. Recent studies propose that neuromelanin-sensitive magnetic resonance imaging (NM-MRI) holds promise as an imaging biomarker. In this review, we summarize the latest findings concerning NM-MRI characteristics at various stages in patients with PD and those with atypical parkinsonism. In conclusion, alterations in neuromelanin within the LC are associated with non-motor symptoms and prove to be a reliable imaging biomarker in the prodromal phase of PD. Furthermore, NM-MRI demonstrates efficacy in differentiating progressive supranuclear palsy (PSP) from PD and multiple system atrophy with predominant parkinsonism. The spatial patterns of changes in the SNpc can be indicative of PD progression and aid in distinguishing between PSP and synucleinopathies. We recommend that patients with PD and individuals at risk for PD undergo regular NM-MRI examinations. This technology holds the potential for widespread use in PD diagnosis.


Assuntos
Biomarcadores , Imageamento por Ressonância Magnética , Melaninas , Doença de Parkinson , Humanos , Melaninas/metabolismo , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Imageamento por Ressonância Magnética/métodos , Biomarcadores/metabolismo , Locus Cerúleo/diagnóstico por imagem , Locus Cerúleo/metabolismo , Parte Compacta da Substância Negra/diagnóstico por imagem , Parte Compacta da Substância Negra/metabolismo
3.
Ann Nutr Metab ; 79(3): 334-342, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37253343

RESUMO

INTRODUCTION: Vitamin K (VK) as well as vitamin D (VD) plays an important role in osteoporosis. Vitamin K1 (VK1), vitamin K2 (VK2, menaquinone-4 (MK-4), and menaquinone-7 (MK-7)) are significant for the metabolism of skeletal muscle. 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 (25(OH)D2 and 25(OH)D3) reflect circulating VD levels. More sensitive measurements remain to be developed. In the present study, a new high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the determination of VK1, VK2 (MK-4 and MK-7), as well as 25(OH)D2 and 25(OH)D3 levels in human serum. METHODS: We developed a simple LC-MS/MS method for the determination of VK1, MK-4, MK-7, 25(OH)D2, and 25(OH)D3 levels in human serum and validated the method in a study cohort of 200 patients divided into the premenopausal women group and postmenopausal osteoporosis patient group. RESULTS: The overall precision (coefficient of variation) ranged from 2.66 to 10.11% in the specified working range (0.05-5 ng/mL) for VK1, MK-4, and MK-7. Serum VK1, MK-4, and MK-7 levels in postmenopausal women with osteoporosis were 1.187 ± 0.094 ng/mL, 0.058 ± 0.009 ng/mL, and 0.885 ± 0.064 ng/mL, respectively (mean ± standard deviation). Serum VK1, MK-4, and MK-7 levels in premenopausal women were 1.143 ± 0.103 ng/mL, 0.028 ± 0.003 ng/mL, and 1.553 ± 0.226 ng/mL, respectively. Serum 25(OH)D2 and 25(OH)D3 levels in postmenopausal women with osteoporosis were 0.757 ± 0.056 ng/mL and 11.72 ± 0.632 ng/mL, respectively. Serum 25(OH)D2 and 25(OH)D3 levels in premenopausal were 1.793 ± 0.575 ng/mL and 12.42 ± 1.069 ng/mL, respectively. CONCLUSION: A new LC-MS/MS method for determination of serum VK and VD levels was evaluated and validated. MK-7 in plasma decreased earlier than VD in postmenopausal osteoporosis patients. MK-7 status is significantly associated with osteoporosis and could be considered a predictable biomarker in the diagnosis of osteoporosis in postmenopausal women.


Assuntos
Osteoporose Pós-Menopausa , Osteoporose , Humanos , Feminino , Cromatografia Líquida/métodos , Vitamina K 1 , Espectrometria de Massas em Tandem/métodos , Vitamina D , Calcifediol , 25-Hidroxivitamina D 2 , Vitaminas
4.
BMC Genomics ; 23(1): 797, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460960

RESUMO

BACKGROUND: Cetacean hindlimbs were lost and their forelimb changed into flippers characterized by webbed digits and hyperphalangy, thus allowing them to adapt to a completely aquatic environment. However, the underlying molecular mechanism behind cetacean limb development remains poorly understood. RESULTS: In the present study, we explored the evolution of 16 limb-related genes and their cis-regulatory elements in cetaceans and compared them with that of other mammals. TBX5, a forelimb specific expression gene, was identified to have been under accelerated evolution in the ancestral branches of cetaceans. In addition, 32 cetacean-specific changes were examined in the SHH signaling network (SHH, PTCH1, TBX5, BMPs and SMO), within which mutations could yield webbed digits or an additional phalange. These findings thus suggest that the SHH signaling network regulates cetacean flipper formation. By contrast, the regulatory activity of the SHH gene enhancer-ZRS in cetaceans-was significantly lower than in mice, which is consistent with the cessation of SHH gene expression in the hindlimb bud during cetacean embryonic development. It was suggested that the decreased SHH activity regulated by enhancer ZRS might be one of the reasons for hindlimb degeneration in cetaceans. Interestingly, a parallel / convergent site (D42G) and a rapidly evolving CNE were identified in marine mammals in FGF10 and GREM1, respectively, and shown to be essential to restrict limb bud size; this is molecular evidence explaining the convergence of flipper-forelimb and shortening or degeneration of hindlimbs in marine mammals. CONCLUSIONS: We did evolutionary analyses of 16 limb-related genes and their cis-regulatory elements in cetaceans and compared them with those of other mammals to provide novel insights into the molecular basis of flipper forelimb and hindlimb loss in cetaceans.


Assuntos
Membro Anterior , Polidactilia , Feminino , Gravidez , Animais , Camundongos , Membro Posterior , Extremidades , Desenvolvimento Embrionário , Mamíferos
5.
Genomics ; 113(5): 2925-2933, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34166750

RESUMO

Cetaceans have evolved elongated soft-tissue flipper with digits made of hyperphalangy. Cetaceans were found to have 2-3 more alanine residues in Hoxd13 than other mammals, which were suggested to be related to their flipper. However, how Hoxd13 regulates other genes and induces hyperphalangy in cetaceans remain poorly understood. Here, we overexpressed the bottlenose dolphin Hoxd13 in zebrafish (Danio rerio). Combined with transcriptome data and evolutionary analyses, our results revealed that the Wingless/Integrated (Wnt) and Hedgehog signaling pathways and multiple genes might regulate hyperphalangy development in cetaceans. Meanwhile, the Notch and mitogen-activated protein kinase (Mapk) signaling pathways and Fibroblast growth factor receptor 1 (Fgfr1) are probably correlated with interdigital tissues retained in the cetacean flipper. In conclusion, this is the first study to use a transgenic zebrafish to explore the molecular evolution of Hoxd13 in cetaceans, and it provides new insights into cetacean flipper formation.


Assuntos
Golfinho Nariz-de-Garrafa , Peixe-Zebra , Animais , Evolução Biológica , Golfinho Nariz-de-Garrafa/genética , Cetáceos/genética , Proteínas Hedgehog/genética , Peixe-Zebra/genética
6.
BMC Genomics ; 22(1): 763, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702182

RESUMO

BACKGROUND: Mammals have wide variations in testicular position, with scrotal testes in some species and ascrotal testes in others. Although cryptorchidism is hazardous to human health, some mammalian taxa are natural cryptorchids. However, the evolution of testicular position and the molecular mechanisms underlying the maintenance of health, including reproductive health, in ascrotal mammals are not clear. RESULTS: In the present study, comparative genomics and evolutionary analyses revealed that genes associated with the extracellular matrix and muscle, contributing to the development of the gubernaculum, were involved in the evolution of testicular position in mammals. Moreover, genes related to testicular position were significantly associated with spermatogenesis and sperm fertility. These genes showed rapid evolution and the signature of positive selection, with specific substitutions in ascrotal mammals. Genes associated with testicular position were significantly enriched in functions and pathways related to cancer, DNA repair, DNA replication, and autophagy. CONCLUSIONS: Our results revealed that alterations in gubernaculum development contributed to the evolution of testicular position in mammals and provided the first support for two hypotheses for variation in testicular position in mammals, the "cooling hypothesis", which proposes that the scrotum provides a cool environment for acutely heat-sensitive sperm and the "training hypothesis", which proposes that the scrotum develops the sperm by exposing them to an exterior environment. Further, we identified cancer resistance and DNA repair as potential protective mechanisms in natural cryptorchids. These findings provide general insights into cryptorchidism and have implications for health and infertility both in humans and domestic mammals.


Assuntos
Criptorquidismo , Animais , Criptorquidismo/genética , Genômica , Humanos , Masculino , Mamíferos/genética , Espermatogênese/genética , Testículo
7.
Stem Cells ; 38(11): 1467-1478, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32526076

RESUMO

Wnt/ß-catenin signaling regulates progenitor cell fate decisions during lung development and in various adult tissues. Ectopic activation of Wnt/ß-catenin signaling promotes tissue repair in emphysema, a devastating lung disease with progressive loss of parenchymal lung tissue. The identity of Wnt/ß-catenin responsive progenitor cells and the potential impact of Wnt/ß-catenin signaling on adult distal lung epithelial progenitor cell function in emphysema are poorly understood. Here, we used TCF/Lef:H2B/GFP reporter mice to investigate the role of Wnt/ß-catenin signaling in lung organoid formation. We identified an organoid-forming adult distal lung epithelial progenitor cell population characterized by a low Wnt/ß-catenin activity, which was enriched in club and alveolar epithelial type (AT)II cells. Endogenous Wnt/ß-catenin activity was required for the initiation of multiple subtypes of distal lung organoids derived from the Wntlow epithelial progenitors. Further ectopic Wnt/ß-catenin activation specifically led to an increase in alveolar organoid number; however, the subsequent proliferation of alveolar epithelial cells in the organoids did not require constitutive Wnt/ß-catenin signaling. Distal lung epithelial progenitor cells derived from the mouse model of elastase-induced emphysema exhibited reduced organoid forming capacity. This was rescued by Wnt/ß-catenin signal activation, which largely increased the number of alveolar organoids. Together, our study reveals a novel mechanism of lung epithelial progenitor cell activation in homeostasis and emphysema.


Assuntos
Enfisema/genética , Homeostase/fisiologia , Células-Tronco/metabolismo , beta Catenina/metabolismo , Animais , Enfisema/patologia , Humanos , Camundongos , Via de Sinalização Wnt
8.
J Mol Evol ; 88(6): 521-535, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32458105

RESUMO

Fossil evidence suggests that cetaceans evolved from artiodactylans. Thus, there was a major dietary change from herbivorous to carnivorous during their transition from a terrestrial to an aquatic environment. However, the molecular evolutionary mechanisms underlying this dietary switch have not been well investigated. Evidence of positive selection of digestive proteinases and lipases of cetaceans was detected: (1) For the four pancreatic proteinase families (carboxypeptidase, trypsin, chymotrypsin, and elastase) examined in this study, each family included only a single intact gene (e.g., CPA1, PRSS1, CTRC, and CELA3B) that had no ORF-disrupted or premature stop codons, whereas other members of each family had become pseudogenized. Further selective pressure analysis showed that three genes (PRSS1, CTRC, and CELA3B) were subjected to significant positive selection in cetaceans. (2) For digestive proteinases from the stomach, PGA was identified to be under positive selection. (3) Intense positive selection was also detected for the lipase gene PLRP2 in cetaceans. In addition, parallel /convergent amino acid substitutions between cetaceans and carnivores, two groups of mammals that have evolved similar feeding habits, were identified in 10 of the 12 functional genes. Although pseudogenization resulted in each family of pancreatic proteinases only retaining one intact gene copy in cetacean genomes, positive selection might have driven pancreatic proteinases, stomach proteinases, and lipases to adaptively evolve a stronger ability to digest a relatively higher proportion of proteins and lipids from animal foods. This study can provide some novel insights into the molecular mechanism of cetacean dietary changes during their transition from land to sea.


Assuntos
Cetáceos , Dieta/veterinária , Evolução Molecular , Lipase , Peptídeo Hidrolases , Animais , Filogenia , Seleção Genética
9.
J Hered ; 110(3): 332-339, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30844043

RESUMO

Cetaceans are a suborder of secondarily adapted aquatic mammals with an enigmatic history involving a transition from land to sea approximately 55 Mya. During the transition period, cetaceans would have faced many new pathogen challenges, but limited information is available about the adaptive immune system of these mammals. The major histocompatibility complex (MHC) family plays a key role in antigen recognition and presentation in adaptive immunity, which is believed to have evolved in response to pathogens. In the present study, MHC class II loci were characterized in 7 published cetacean genome assemblies and the genomic organization of cetaceans was compared with that of their terrestrial relatives, the cow, sheep, and pig. A total of 9 MHC class II loci were identified in the cetacean genomes: DRA, DRB, DQA, DQB, DPB, DOA, DOB, DMA, and DMB. Sequences from 8 of the 9 genes included intact coding regions and were presumably functional. The organization of the MHC class II loci was conserved across the examined mammalian species, whereas the orientation and number of the alpha and beta genes varied among the species. The phylogenetic reconstruction of all MHC genes from Cetartiodactyla suggested that alpha and beta genes had different topologies. Additionally, based on a phylogenetic reconstruction of the multi-locus DRB, 2 (DRB1 and DRB2) of the 4 putative gene copies were hypothesized to have duplicated and evolved during the radiation of cetaceans.


Assuntos
Cetáceos/classificação , Cetáceos/genética , Genes MHC da Classe II , Loci Gênicos , Genoma , Genômica , Filogenia , Animais , Genômica/métodos
10.
J Mol Evol ; 86(2): 138-149, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29455279

RESUMO

Pattern recognition receptors (PRRs) are specialized receptors that represent a key component of the host innate immune system. Whether molecular evolutionary history of different PRR classes have involved different genetic mechanisms underlying diverse pathogen environment in mammals, and whether distinct ecology of mammals may have imposed divergent selective pressures on the evolution of the PRRs, remained unknown. To test these hypotheses, we investigated the characterization of 20 genes belonging to four PRR classes in mammals. Evidence of positive selection was found in most (17 of 20) PRR genes examined, and most positively selected sites (84%) undergoing radical changes were found to fall in important functional regions, consistent with the co-evolutionary dynamics between the hosts and their microbial counterparts. We found different evolutionary patterns in different PRR classes, with the highest level of positive selection in C-type lectin receptor (CLR) family, suggesting that the capability of CLRs in response to a wide variety of ligands might explain their malleability to selection pressures. Tests using branch models that partitioned the data along habitat and social behavior found significant evidence of divergent selective pressures of PRRs among mammalian groups. Interestingly, species-specific evolution was detected on RIG-I-like helicase genes (RLRs) in cetaceans, suggesting that RLRs might play a critical role in the defense against widespread marine RNA viruses during their divergence and radiation into marine habitats. This study provides a comprehensive look at the evolutionary patterns and implications of mammalian PRRs, and highlights the importance of ecological influences in molecular adaptation.


Assuntos
Imunidade Inata/genética , Mamíferos/genética , Receptores de Reconhecimento de Padrão/genética , Adaptação Fisiológica , Animais , Evolução Biológica , Proteína DEAD-box 58/genética , Ecossistema , Evolução Molecular , Interações Hospedeiro-Patógeno/genética , Lectinas Tipo C/genética , Filogenia , Receptores de Reconhecimento de Padrão/metabolismo , Seleção Genética/genética , Especificidade da Espécie
11.
Haematologica ; 103(3): 466-476, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29217775

RESUMO

Chemotherapeutic agents, e.g., cytarabine and doxorubicin, cause DNA damage. However, it remains unknown whether such agents differentially regulate cell cycle arrest in distinct types of B-cell lymphomas, and whether this phenotype can be exploited for developing new therapies. We treated various types of B cells, including primary and B lymphoma cells, with cytarabine or doxorubicin, and determined DNA damage responses, cell cycle regulation and sensitivity to a Wee1 inhibitor. We found that cyclin A2/B1 upregulation appears to be an intrinsic programmed response to DNA damage; however, different types of B cells arrest in distinct phases of the cell cycle. The Wee1 inhibitor significantly enhanced the apoptosis of G2 phase-arrested B-cell lymphomas by inducing premature entry into mitosis and mitotic catastrophe, whereas it did not affect G1/S-phase-arrested lymphomas. Cytarabine-induced G1-arrest can be converted to G2-arrest by doxorubicin treatment in certain B-cell lymphomas, which correlates with newly acquired sensitivity to the Wee1 inhibitor. Consequently, the Wee1 inhibitor together with cytarabine or doxorubicin inhibited tumor growth in vitro and in vivo more effectively, providing a potential new therapy for treating B-cell lymphomas. We propose that the differential cell cycle arrest can be exploited to enhance the chemosensitivity of B-cell lymphomas.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/antagonistas & inibidores , Linfoma de Células B/patologia , Proteínas Nucleares/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Citarabina/farmacologia , Dano ao DNA/efeitos dos fármacos , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Humanos , Linfoma de Células B/tratamento farmacológico , Camundongos
12.
Biotechnol Appl Biochem ; 65(5): 672-679, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29644748

RESUMO

This study aimed to investigate the effect of Scolopin-2, a cationic antimicrobial peptide from centipede venoms, and amidated Scolopin-2 on Hela cell viability in vitro and in vivo. The cellular proliferation was investigated with the MTT assay. Confocal laser scanning, flow cytometry, and Western blot analysis were employed to localize Scolopin-2-NH2 in Hela cells and to study the caused cells apoptosis. We subcutaneously injected Hela cells into BALB/c nude mice and studied if Scolopin-2-NH2 suppressed tumor growth in the mice. Scolopin-2-NH2 inhibited Hela proliferation in vitro in a dose-dependent manner with an IC50 of 35 µM. In addition, Scolopin-2-NH2 combined with mitochondria and regulated caspase-related apoptosis pathways in Hela cells. Scolopin-2-NH2 significantly suppressed tumor growth in the tumor-bearing mice without side effects, such as weight loss or abnormal changes in tissues, including liver, spleen, kidney, and lung. These results indicate Scolopin-2-NH2 may be a good therapeutic candidate for the treatment of Hela cervical cancer.


Assuntos
Amidas/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Animais , Western Blotting , Linhagem Celular Tumoral , Citometria de Fluxo , Células HEK293 , Humanos , Concentração Inibidora 50 , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
13.
BMC Evol Biol ; 17(1): 206, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851290

RESUMO

BACKGROUND: Cetacean brain size expansion is an enigmatic event in mammalian evolution, yet its genetic basis remains poorly explored. Here, all exons of the seven primary microcephaly (MCPH) genes that play key roles in size regulation during brain development were investigated in representative cetacean lineages. RESULTS: Sequences of MCPH2-7 genes were intact in cetaceans but frameshift mutations and stop codons was identified in MCPH1. Extensive positive selection was identified in four of six intact MCPH genes: WDR62, CDK5RAP2, CEP152, and ASPM. Specially, positive selection at CDK5RAP2 and ASPM were examined along lineages of odontocetes with increased encephalization quotients (EQ) and mysticetes with reduced EQ but at WDR62 only found along odontocete lineages. Interestingly, a positive association between evolutionary rate (ω) and EQ was identified for CDK5RAP2 and ASPM. Furthermore, we tested the binding affinities between Calmodulin (CaM) and ASPM IQ motif in cetaceans because only CaM combined with IQ, can ASPM perform the function in determining brain size. Preliminary function assay showed binding affinities between CaM and IQ motif of the odontocetes with increased EQ was stronger than for the mysticetes with decreased EQ. In addition, evolution rate of ASPM and CDK5RAP2 were significantly related to mean group size (as one measure of social complexity). CONCLUSIONS: Our study investigated the genetic basis of cetacean brain size evolution. Significant positive selection was examined along lineages with both increased and decreased EQ at CDK5RAP2 and ASPM, which is well matched with cetacean complex brain size evolution. Evolutionary rate of CDK5RAP2 and ASPM were significantly related to EQ, suggesting that these two genes may have contributed to EQ expansion in cetaceans. This suggestion was further indicated by our preliminary function test that ASPM might be mainly linked to evolutionary increases in EQ. Most strikingly, our results suggested that cetaceans evolved large brains to manage complex social systems, consisting with the 'social brain hypothesis', as evolutionary rate of ASPM and CDK5RAP2 were significantly related to mean group size.


Assuntos
Adaptação Fisiológica , Encéfalo/anatomia & histologia , Cetáceos/anatomia & histologia , Cetáceos/genética , Evolução Molecular , Microcefalia/genética , Proteínas do Tecido Nervoso/genética , Aminoácidos/genética , Animais , Humanos , Tamanho do Órgão/genética , Filogenia , Ligação Proteica , Análise de Regressão , Seleção Genética
14.
Mol Biol Evol ; 33(12): 3144-3157, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27651393

RESUMO

Although cetaceans (whales, porpoises, and dolphins) have multi-chambered stomachs, feeding habits of modern cetaceans have dramatically changed from herbivorous to carnivorous. However, the genetic basis underlying this dietary switch remains unexplored. Here, we present the first systematic investigation of 10 digestive enzymes genes (i.e., CYP7A1, CTRC, LIPC, LIPF, PNLIP, PGC, PRSS1, SI, SLC5A1, and TMPRSS15) of representative cetaceans, and the evolutionary trajectory of RNASE1 in cetartiodactylans. Positive selections were detected with proteinases (i.e., CTRC, PRSS1, and TMPRSS15) and lipases (i.e., CYP7A1, LIPF, and PNLIP) suggesting that cetaceans have evolved an enhanced digestion capacity for proteins and lipids, the major nutritional components of their prey (fishes and invertebrates). In addition, it was found that RNASE1 gene duplicated after the cetartiodactylan speciation and two independent gene duplication events took place in Camelidae and Ruminantia. Positive selection was detected with RNASE1 of Camelidae and Bovidae, suggesting enhanced digestive efficiency in the ruminants. Remarkably, even though the ancestors of cetaceans were terrestrial artiodactyls that are herbivorous, modern cetaceans lost the pancreatic RNASE1 copy with digestive function, which is in accordance with the dietary change from herbivorous to carnivorous. In sum, this is the first study that provides new insights into the evolutionary mechanism of dietary switch in cetaceans.


Assuntos
Cetáceos/genética , Cetáceos/metabolismo , Ribonuclease Pancreático/genética , Ribonuclease Pancreático/metabolismo , Animais , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Quimotripsina/genética , Quimotripsina/metabolismo , Golfinhos/genética , Golfinhos/metabolismo , Evolução Molecular , Comportamento Alimentar/fisiologia , Duplicação Gênica , Lipase/genética , Filogenia , Receptores Odorantes/genética , Seleção Genética , Transportador 1 de Glucose-Sódio/genética , Tripsina/genética , Baleias/genética , Baleias/metabolismo
16.
BMC Evol Biol ; 14: 218, 2014 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-25305673

RESUMO

BACKGROUND: Five basic taste modalities, sour, sweet, bitter, salt and umami, can be distinguished by humans and are fundamental for physical and ecological adaptations in mammals. Molecular genetic studies of the receptor genes for these tastes have been conducted in terrestrial mammals; however, little is known about the evolution and adaptation of these genes in marine mammals. RESULTS: Here, all five basic taste modalities, sour, sweet, bitter, salt and umami, were investigated in cetaceans. The sequence characteristics and evolutionary analyses of taste receptor genes suggested that nearly all cetaceans may have lost all taste modalities except for that of salt. CONCLUSIONS: This is the first study to comprehensively examine the five basic taste modalities in cetaceans with extensive taxa sampling. Our results suggest that cetaceans have lost four of the basic taste modalities including sour, sweet, umami, and most of the ability to sense bitter tastes. The integrity of the candidate salt taste receptor genes in all the cetaceans examined may be because of their function in Na(+) reabsorption, which is key to osmoregulation and aquatic adaptation.


Assuntos
Cetáceos/fisiologia , Evolução Molecular , Receptores Acoplados a Proteínas G/genética , Animais , Evolução Biológica , Cetáceos/classificação , Cetáceos/genética , Receptores Acoplados a Proteínas G/fisiologia , Cloreto de Sódio/metabolismo , Papilas Gustativas/fisiologia
17.
Appl Opt ; 53(23): 5259-63, 2014 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-25320937

RESUMO

We propose and demonstrate a fiber Bragg grating sensor interrogator based on a 2D imaging system using a virtually imaged phased array (VIPA) and infrared camera. There are no moving parts, and the interrogator has good stability and reliability. The absolute wavelength accuracy of the interrogator is better than that of traditional diffraction grating and a 1D-imaging-system-based method, thanks to the VIPA's high spectral resolution and large angular dispersion. The wavelength resolution of the interrogator is about 7 pm, and the spectral range of this interrogator is more than 30 nm. The optimum setup for the best wavelength resolution is analyzed.

18.
Sleep ; 47(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38289699

RESUMO

Marine mammals, especially cetaceans, have evolved a very special form of sleep characterized by unihemispheric slow-wave sleep (USWS) and a negligible amount or complete absence of rapid-eye-movement sleep; however, the underlying genetic mechanisms remain unclear. Here, we detected unique, significant selection signatures in basic helix-loop-helix ARNT like 2 (BMAL2; also called ARNTL2), a key circadian regulator, in marine mammal lineages, and identified two nonsynonymous amino acid substitutions (K204E and K346Q) in the important PER-ARNT-SIM domain of cetacean BMAL2 via sequence comparison with other mammals. In vitro assays revealed that these cetacean-specific mutations specifically enhanced the response to E-box-like enhancer and consequently promoted the transcriptional activation of PER2, which is closely linked to sleep regulation. The increased PER2 expression, which was further confirmed both in vitro and in vivo, is beneficial for allowing cetaceans to maintain continuous movement and alertness during sleep. Concordantly, the locomotor activities of zebrafish overexpressing the cetacean-specific mutant bmal2 were significantly higher than the zebrafish overexpressing the wild-type gene. Subsequently, transcriptome analyses revealed that cetacean-specific mutations caused the upregulation of arousal-related genes and the downregulation of several sleep-promoting genes, which is consistent with the need to maintain hemispheric arousal during USWS. Our findings suggest a potential close relationship between adaptive changes in BMAL2 and the remarkable adaptation of USWS and may provide novel insights into the genetic basis of the evolution of animal sleep.


Assuntos
Fatores de Transcrição ARNTL , Cetáceos , Sono de Ondas Lentas , Animais , Locomoção/genética , Mamíferos , Sono/genética , Sono de Ondas Lentas/genética , Peixe-Zebra , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Cetáceos/genética
19.
Front Aging Neurosci ; 16: 1377994, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650864

RESUMO

Introduction: Peripheral inflammatory responses are suggested to play a major role in the pathophysiology of Parkinson's disease (PD). The neutrophil-to-lymphocyte ratio (NLR), a new recognized biomarker, can reflect peripheral inflammation in PD. However, the association between the NLR and dopaminergic degeneration in PD remains unclear. Methods: In this retrospective study, 101 enrolled PD patients were categorized into early-stage and advanced-stage PD based on the Hoehn and Yahr (HY) scale. We evaluated the clinical characteristics, peripheral immune profile, and 11C-CFT striatal dopamine transporter (DAT) binding levels. Linear regression analyses were employed to assess the associations between NLR and striatal DAT levels at different stages in PD patients. Results: Covariate-controlled regression analysis revealed that higher NLR was significantly associated with lower DAT levels in the caudate (ß = -0.27, p = 0.003) and the putamen (ß = -0.27, p = 0.011). Moreover, in the early-stage PD subgroup, a similar association was observed (caudate: ß = -0.37, p = 0.013; putamen: ß = -0.45, p = 0.005). The lymphocytes count was correlated positively with the striatal DAT levels in the Spearman correlation analysis whether in total patients (caudate: ρ = 0.25, p = 0.013; putamen: ρ = 0.22, p = 0.026) or in the early-stage subgroup (caudate: ρ = 0.31, p = 0.023, putamen: ρ = 0.34, p = 0.011). Conclusion: Dopaminergic degeneration is associated with peripheral inflammation in PD. The NLR, a widely used inflammatory marker, may have the potential to reflect the degree of dopaminergic degeneration in individuals with early-stage PD.

20.
Protein Expr Purif ; 92(2): 230-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24145284

RESUMO

Antimicrobial peptide scolopin 1 (AMP-scolopin 1) is a small cationic peptide identified from centipede venoms of Scolopendra subspinipes mutilans. It has broad-spectrum activities against bacteria, fungi, and tumor cells, which may possibly be used as an antimicrobial agent. We first report here the application of small ubiquitin-related modifier (SUMO) fusion technology to the expression and purification of cationic antimicrobial peptide AMP-scolopin 1. The fusion protein expressed in a soluble form was purified to a purity of 95% by Ni-IDA chromatography. After the SUMO-scolopin 1 fusion protein was cleaved by the SUMO protease at 30°C for 1 h, the cleaved sample was reapplied to a Ni-IDA. The recombinant scolopin1 had similar antimicrobial properties to the synthetic scolopin 1. Thus, we successfully established a system for purifying peptide of centipede, which could be used for further research.


Assuntos
Anti-Infecciosos/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Venenos de Artrópodes/metabolismo , Artrópodes/enzimologia , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Venenos de Artrópodes/química , Venenos de Artrópodes/genética , Artrópodes/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/química , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética
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