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1.
The New World tropics represents the most diverse region for tachinid parasitoids (Diptera: Tachinidae), but it also contains the most narrowly defined, and possibly the most confusing, tachinid genera of any biogeographic region. This over-splitting of genera and taxonomic confusion has limited progress toward our understanding the family in this region and much work is needed to revise, redefine, and make sense of the profusion of finely split taxa. In a recent analysis of the Neotropical genus Erythromelana Townsend, two species previously assigned to this genus, Euptilodegeeria obumbrata (Wulp) and Myiodoriops marginalis Townsend were reinstated as monotypic genera. In the present study, we demonstrate that Euptilodegeeria obumbrata (Wulp), previously assigned to three different genera, represents in fact a species of the large New World genus Eucelatoria Townsend, in which females possess a sharp piercer for oviposition. We also show that the species Eucelatoria carinata (Townsend) belongs to the same species group as Eucelatoria obumbrata, which we here define and characterize as the Eucelatoria obumbrata species group. Additionally, we describe Eucelatoria flava sp. n. as a new species within the Eucelatoria obumbrata species group. Finally, we redescribe the genus Myiodoriops Townsend and the single species Myiodoriops marginalis Townsend.  相似文献   

2.
Juan J. Morrone 《ZooKeys》2013,(273):15-71
The phylogenetic relationships of the genera of Listroderini LeConte, 1876 are analyzed based on 58 morphological characters. The genera are grouped in four clades, which are given subtribal status: Macrostyphlina new subtribe (Adioristidius, Amathynetoides, Andesianellus, Macrostyphlus, Nacodius and Puranius), Palaechthina Brinck, 1948 (Anorthorhinus, Gunodes, Haversiella, Inaccodes, Listronotus, Neopachytychius, Palaechthus, Palaechtodes, Steriphus and Tristanodes), Falklandiina new subtribe (Falklandiellus, Falklandiopsis, Falklandius, Gromilus, Lanteriella, Liparogetus, Nestrius and Telurus), and Listroderina (Acroriellus, Acrorius, Acrostomus, Antarctobius, Germainiellus, Hyperoides, Lamiarhinus, Listroderes, Methypora, Philippius, Rupanius and Trachodema). The subtribes are characterized and keys to identify them and their genera are provided. Listroderini have four main biogeographical patterns: Andean (Macrostyphlina), Andean-New Zealand (Falklandiina), Andean-Neotropical-Australian (Listroderina) and Andean-Neotropical-Australian-New Zealand-Nearctic-Tristan da Cunha-Gough islands (Palaechthina). Geographical paralogy, particularly evident in the Subantarctic subregion of the Andean region, suggests that Listroderini are an ancient Gondwanic group, in which several extinction events might have obscured relationships among the areas.  相似文献   

3.
This study was designed to investigate the relationship between the microclimate temperature and clothing insulation (Icl) under comfortable environmental conditions. In total, 20 subjects (13 women, 7 men) took part in this study. Four environmental temperatures were chosen: 14°C (to represent March/April), 25°C (May/June), 29°C (July/August), and 23°C (September/October). Wind speed (0.14ms-1) and humidity (45%) were held constant. Clothing microclimate temperatures were measured at the chest (Tchest) and on the interscapular region (Tscapular). Clothing temperature of the innermost layer (Tinnermost) was measured on this layer 30 mm above the centre of the left breast. Subjects were free to choose the clothing that offered them thermal comfort under each environmental condition. We found the following results. 1) All clothing factors except the number of lower clothing layers (Llower), showed differences between the different environmental conditions (P<0.05). The ranges of Tchest were 31.6 to 33.5°C and 32.2 to 33.4°C in Tscapular. The range of Tinnermost was 28.6 to 32.0°C. The range of the upper clothing layers (Lupper) and total clothing mass (Mtotal) was 1.1 to 3.2 layers and 473 to 1659 g respectively. The range of Icl was 0.78 to 2.10 clo. 2) Post hoc analyses showed that analysis of Tinnermost produced the same results as for that of Icl. Likewise, the analysis of Lupper produced the same result as the analysis of the number of total layers (Ltotal) within an outfit. 3) Air temperature (ta) had positive relationships with Tchest and Tscapular and with Tinnermost but had inverse correlations with Icl, Mtotal, Lupper and Ltotal. Tchest, Tscapular, and Tinnermost increased as ta rose. 4) Icl had inverse relationships with Tchest and Tinnermost, but positive relationships with Mtotal, Lupper and Ltotal. Icl could be estimated by Mtotal, Lupper, and Tscapular using a multivariate linear regression model. 5) Lupper had positive relationships with Icl and Mtotal, but Llower did not. Subjects hardly changed Llower under environmental comfort conditions between March and October. This indicates that each of the Tchest, Mtotal, and Lupper was a factor in predicting Icl. Tinnermost might also be a more influential factor than the clothing microclimate temperature.  相似文献   

4.
Hourly blood samples were taken throughout a 24h (metabolites) or 48h (hormones) period from three lactating beef (Hereford-cross) and three dairy (Friesian) cows which had been matched for age, stage of lactation (89–110 days) and diet (0.55 kg hay + 4.95 kg concentrates, twice daily). During the first 15 weeks of lactation the beef cows (B) gained weight and gave a poor yield of milk, whereas the dairy animals (D) lost weight but gave a good yield of milk. Significantly higher circulating levels of growth hormone (D = 4.2 ± 0.5 B = 1.5 ± 0.2 ng/ml ± SEMP < 0.005), non-esterified fatty acids (D = 311.0 ± 48.3 B = 181.3 ± 18.9 μEq/1 P<0.0001) and β-hydroxybutyric acid (D= 0.170 ± 0.011 B=0.093 ± 0.0007 mg/mlP<0.0005) were found in the dairy cows, whereas in the beef animals there were significantly higher concentrations of prolactin (D = 8.3 ± 1.1 B = 15.4 ± 1.8 ng/mlP<0.025), insulin (D = 9.5 ± 0.08 B = 28.8 ± 2.6 μU/mlP<0.0001) and glucose (D = 0.654 ± 0.008 B= 0.705 ± 0.009 mg/mlP<0.025). No significant difference in L-lactic acid levels was found at this stage of lactation (D = 0.097 ±0.003 B =0.117 ± 0.006 mg/mlP<0.05).  相似文献   

5.
Three new spider species are described from Iran: Anemesia koponeni sp. n. (♂, Cyrtaucheniidae); Raveniola mazandaranica sp. n. (♂, Nemesiidae) and Sahastata sinuspersica sp. n. (♀, Filistatidae). Cyrtaucheniidae and Sahastata Benoit, 1968 are reported from Iran for the fisrt time.  相似文献   

6.
Material of the paederine genera Domene Fauvel, 1873 and Lathrobium Gravenhorst, 1802 from the Dayao Mountains, southern China, is examined. Eight species are identified, three of them described previously and five undescribed. Four species are described and illustrated for the first time: Domene hei Peng & Li, sp. n., Lathrobium jinxiuense Peng & Li, sp. n., Lathrobium kuan Peng & Li, sp. n. and Lathrobium leii Peng & Li, sp. n. One probably undescribed species of Lathrobium remains unnamed.  相似文献   

7.
Plant chalcone synthase (CHS) and CHS-Like (CHSL) proteins are polyketide synthases. In this study, we evaluated the molecular evolution of this gene family using representative types of CHSL genes, including stilbene synthase (STS), 2-pyrone synthase (2-PS), bibenzyl synthase (BBS), acridone synthase (ACS), biphenyl synthase (BIS), benzalacetone synthase, coumaroyl triacetic acid synthase (CTAS), and benzophenone synthase (BPS), along with their CHS homologs from the same species of both angiosperms and gymnosperms. A cDNA-based phylogeny indicated that CHSLs had diverse evolutionary patterns. STS, ACS, and 2-PS clustered with CHSs from the same species (late diverged pattern), while CTAS, BBS, BPS, and BIS were distant from their CHS homologs (early diverged pattern). The amino-acid phylogeny suggested that CHS and CHSL proteins formed clades according to enzyme function. The CHSs and CHSLs from Polygonaceae and Arachis had unique evolutionary histories. Synonymous mutation rates were lower in late diverged CHSLs than in early diverged ones, indicating that gene duplications occurred more recently in late diverged CHSLs than in early diverged ones. Relative rate tests proved that late diverged CHSLs had unequal rates to CHSs from the same species when using fatty acid synthase, which evolved from the common ancestor with the CHS superfamily, as the outgroup, while the early diverged lineages had equal rates. This indicated that late diverged CHSLs experienced more frequent mutation than early diverged CHSLs after gene duplication, allowing obtaining new functions in relatively short period of time.  相似文献   

8.
The genus Newportia Gervais, 1847, includes some 60 nominal species distributed in the Caribbean islands and from Mexico to central South America. Modern keys to species and subspecies are available, greatly facilitating identification, but some species are based on few specimens and have incomplete documentation of taxonomically-informative characters. In order to explore genetic variability and evolutionary relationships within geographically-widespread morphospecies, specimens of Newportia (Newportia) stolli (Pocock, 1896) and Newportia (Newportia) divergens Chamberlin, 1922, two nominal species distinguished principally by differences in suture patterns on T1, were sequenced for mitochondrial 16S rRNA and cytochrome c oxidase subunit I (COI) genes from populations in southern Mexico, Guatemala, Honduras and Brazil. Newportia (Newportia) stolli is paraphyletic with respect to Newportia (Newportia) divergens within a clade from Guatemala, Honduras, and Chiapas (Mexico), most trees being consistent with a single loss of a connection between the anterior transverse suture on T1, whereas specimens of “Newportia (Newportia) stolli” from Brazil are not closely allied to those from the Mesomerican type area. The widespread morphospecies Newportia (Newportia) monticola Pocock, 1890, was sequenced for the same loci from populations in Costa Rica, Colombia and Brazil, finding that specimens from these areas do not unite as a monophyletic group. Samples of Newportia (Newportia) oreina Chamberlin, 1915, from different regions of Mexico form geographic clusters that resolve as each other’s closest relatives. These results suggest that some widespread species of Newportia may be taxa of convenience more so than natural groupings. In several cases geographic proximity fits the phylogeny better than taxonomy, suggesting that non-monophyletic species do not result from use of inappropriate molecular markers. Molecular identification is possible for specimens missing taxonomically informative morphological characters, notably damaged specimens that lack the ultimate leg pair, a protocol that may also apply to other taxonomically difficult genera that are prone to damage (such as Cryptops).  相似文献   

9.
Despite the alarming rates of deforestation and forest fragmentation, Madagascar still harbors extraordinary biodiversity. However, in many arthropod groups, such as spiders, this biodiversity remains mostly unexplored and undescribed. The first subsocial Madagascan species of the theridiid spider genus Anelosimus were described in 2005 when six new species were found to coexist in the Périnet forest fragment within Andasibe-Mantadia NP. However, this discovery was based only on a few specimens and the extent of this Madagascan radiation has remained unknown. We here report on a thorough survey of >350 colonies from Périnet, and three pilot surveys into additional Madagascar forests (Ambohitantely, Ranamofana, and Montagne d’Ambre). The morphological, molecular and natural history data from these surveys facilitated a revised taxonomy and phylogenetic hypothesis of Madagascan Anelosimus. This subsocial clade currently comprises six previously known (Anelosimus andasibe Agnarsson & Kuntner, 2005, Anelosimus may Agnarsson, 2005, Anelosimus nazariani Agnarsson & Kuntner, 2005, Anelosimus sallee Agnarsson & Kuntner, 2005, Anelosimus salut Agnarsson & Kuntner, 2005, Anelosimus vondrona Agnarsson & Kuntner, 2005) and 10 new species: Anelosimus ata sp. n., Anelosimus buffoni sp. n., Anelosimus darwini sp. n., Anelosimus hookeri sp. n., Anelosimus huxleyi sp. n., Anelosimus lamarcki sp. n., Anelosimus moramora sp. n., Anelosimus tita sp. n., Anelosimus torfi sp. n., Anelosimus wallacei sp. n.. With the exception of Anelosimus may and Anelosimus vondrona, all other species appear to be single forest endemics. While additional sampling is necessary, these data imply a much higher local richness and endemism in Madagascan forests than in any other comparable area globally. The phylogenetic results establish a sister clade relationship between the subsocial Anelosimus in Madagascar and the American ‘eximius group’, and between the solitary Anelosimus decaryi on Madagascar and a solitary American clade. These findings imply duplicate colonizations from America, an otherwise rare biogeographical pattern, calling for more detailed investigation of Anelosimus biogeography.  相似文献   

10.
Equations derived from a contact pressure model of phyllotaxis are relevant to close packing of equal spheres on a cylindrical surface. They provide a general method of calculating the parameters for microscopic biological structures that are assembled in helical arrangements of protein monomers. In the triple-contact case of hexagonal packing, with km, kn and k(m+n) contact parastichies respectively, where m and n are relatively prime, the divergence angle d and the normalized internode distance r on the k fundamental spirals are completely determined by m, n and k, and formulas are given for calculating them. In the double-contact case of rhombic packing, with km and kn contact parastichies respectively, where m < n, d is a function of r, and the domain of r is the interval between the value of r determined for the triple-contact case of km, kn and k(m+n) parastichies and the value of r determined for the triple-contact case of k(n-m), km and kn parastichies. Here r and d can be determined from the measured ratio of the radius of the cylindrical surface to the radius of the spheres.  相似文献   

11.
Gunnar Brehm 《ZooKeys》2015,(537):131-156
Three new Hagnagora Druce species (Geometridae, Larentiinae) are described: Hagnagora richardi Brehm, sp. n. from Ecuador, Hagnagora hedwigae Brehm, sp. n. from Ecuador, and Hagnagora mirandahenrichae Brehm, sp. n. from Costa Rica. A checklist of taxa assigned to Hagnagora is provided. Hagnagora is provisionally divided into six clades: the anicata clade (6 species), the buckleyi clade (3 species), the croceitincta clade (3 species), the ephestris clade (3 species), the mortipax clade (4 species) and Hagnagora subrosea (1 species). Two taxa are revived from synonymy: Hagnagora catagrammina Druce, stat. rev. and Hagnagora luteoradiata Thierry-Mieg, stat. rev. Two taxa are reinstated from subspecies to species level: Hagnagora acothysta Schaus, stat. rev. and Hagnagora jamaicensis Schaus, stat. rev. Four taxa are provisionally removed from Hagnagora: Hagnagoraignipennis, Hagnagoramesenata, Hagnagoravittata, and Hagnagoraceraria. After these changes, the genus Hagnagora now comprises 20 valid species.  相似文献   

12.
We studied rdgB, a retinal degeneration mutant, and trp, a phototransduction mutant, separately and in combination in Drosophila. First we showed that trp did not block degeneration in white-eyed rdgB mutants. Thus, rdgB was useful in determining the defects which trp caused in the compound eye receptors R7 and R8; this is because rdgB selectively eliminates R1-6 photoreceptors which would, if present, dominate the compound eye responses. R7 and R8 both express the trptransient receptor potential phenotype in trp mutants. The trp mutation does not change receptor spectral sensitivities, nor does it alter the dark stability of R1-6's and R7's metarhodopsins as judged by dark adaptation studies. The dark adaptation is not significantly affected by trp. However, trp slows the dark adaptation of R8 considerably and seems to make the blue-induced inactivation of R1-6 less stable.  相似文献   

13.
Members of the genus Parachironomus Lenz known from China and Japan are revised, and a key to their male adults is given. Parachironomus poyangensis sp. n. is described in this life stage. Parachironomus frequens (Johannsen) and Parachironomus monochromus (van der Wulp) are recorded from China for the first time, thus are redescribed from Chinese specimens. Parachironomus kamaabeus Sasa & Tanaka and Parachironomus toneabeus Sasa & Tanaka are new junior synonyms of Parachironomus frequens. Three Chinese or Japanese species formerly placed in Parachironomus are transferred to other genera, resulting in the new combinations Cryptochironomus inafegeus (Sasa, Kitami & Suzuki), Demicryptochironomus (Irmakia) lobus (Yan, Sæther, Jin & Wang), and Microchironomus lacteipennis (Kieffer). Chironomus sauteri Kieffer, Parachironomus kisobilobalis Sasa & Kondo and Parachironomus kuramaexpandus Sasa are removed from Parachironomus; the last of these three denotes a valid species of uncertain generic placement, the first two are nomina dubia.  相似文献   

14.
Cunaxidae are predaceous mites found in a variety of habitats. This work provides comprehensive keys to world subfamilies, genera, and species. Diagnoses and historical reviews are provided for subfamilies and genera.Cunaxa boneti, C. denmarki, C. exoterica, C. floridanus, C. lehmanae, C. lukoschusi, C. metzi, C. myabunderensis, C newyorkensis, C. rackae, C. reevesi, and C. reticulatus are moved to Rubroscirus and C. otiosus, C. valentis, and C. rasile are returned to Rubroscirus. Cunaxoides neopectinatus is moved to Pulaeus. Neocunaxoides pradhani and N. gilbertoi are transferred to Scutopalus. Pulaeus minutus and P. subterraneus are moved to Lupaeus. Pseudobonzia bakari, P. malookensis, and P. shamshadi are transferred to Neobonzia. Dactyloscirus bifidus is transferred to Armascirus.Scirula papillata is reported from the Western Hemisphere for the first time. Armascirus ozarkensis, A. primigenius, and Dactyloscirus dolichosetosus are reported from new localities.  相似文献   

15.
K+ and Na+ fluxes and ion content have been studied in roots of Atriplex nummularia Lindl. and Avena sativa L. cv Goodfield grown in 3 millimolar K+ with or without 3 or 50 millimolar NaCl. Compartmental analysis was carried out with entire root systems under steady-state conditions.

Increasing ambient Na+ concentrations from 0 to 50 millimolar altered K+, in Atriplex, as follows: slightly decreased the cytoplasmic content (Qc), the vacuolar content (Qv), and the plasma membrane influx and efflux. Xylem transport for K+ decreased by 63% in Atriplex. For oat roots, similar increases in Na+ altered K+ parameters as follows: plasma membrane influx and efflux decreased by about 80%. Qc decreased by 65%, and xylem transport decreased by 91%. No change, however, was observed in Qv for K+. Increasing ambient Na+ resulted in higher (3 to 5-fold) Na+ fluxes across the plasma membrane and in Qc of both species. In Atriplex, Na+ fluxes across the tonoplast and Qv increased as external Na+ was increased. In oat, however, no significant change was observed in Na+ flux across the tonoplast or in Qv as external Na+ was increased. In oat roots, Na+ reduced K+ uptake markedly; in Atriplex, this was not as pronounced. However, even at high Na+ levels, the influx transport system at the plasma membrane of both species preferred K+ over Na+.

Based upon the Ussing-Teorell equation, it was concluded that active inward transport of K+ occurred across the plasma membrane, and passive movement of K+ occurred across the tonoplast in both species. Na+, in oat roots, was actively pumped out of the cytoplasm to the exterior, whereas, in Atriplex, Na+ was passively distributed between the free space, cytoplasm, and vacuole.

  相似文献   

16.
BackgroundThe Zanzibar Archipelago (Pemba and Unguja islands) is targeted for the elimination of human urogenital schistosomiasis caused by infection with Schistosoma haematobium where the intermediate snail host is Bulinus globosus. Following multiple studies, it has remained unclear if B. nasutus (a snail species that occupies geographically distinct regions on the Archipelago) is involved in S. haematobium transmission on Zanzibar. Additionally, S. haematobium was thought to be the only Schistosoma species present on the Zanzibar Archipelago until the sympatric transmission of S. bovis, a parasite of ruminants, was recently identified. Here we re-assess the epidemiology of schistosomiasis on Pemba and Unguja together with the role and genetic diversity of the Bulinus spp. involved in transmission.Methodology/Principal findingsMalacological and parasitological surveys were conducted between 2016 and 2019. In total, 11,116 Bulinus spp. snails were collected from 65 of 112 freshwater bodies surveyed. Bulinus species identification were determined using mitochondrial cox1 sequences for a representative subset of collected Bulinus (n = 504) and together with archived museum specimens (n = 6), 433 B. globosus and 77 B. nasutus were identified. Phylogenetic analysis of cox1 haplotypes revealed three distinct populations of B. globosus, two with an overlapping distribution on Pemba and one on Unguja. For B. nasutus, only a single clade with matching haplotypes was observed across the islands and included reference sequences from Kenya. Schistosoma haematobium cercariae (n = 158) were identified from 12 infected B. globosus and one B. nasutus collected between 2016 and 2019 in Pemba, and cercariae originating from 69 Bulinus spp. archived in museum collections. Schistosoma bovis cercariae (n = 21) were identified from seven additional B. globosus collected between 2016 and 2019 in Pemba. By analysing a partial mitochondrial cox1 region and the nuclear ITS (1–5.8S-2) rDNA region of Schistosoma cercariae, we identified 18 S. haematobium and three S. bovis haplotypes representing populations associated with mainland Africa and the Indian Ocean Islands (Zanzibar, Madagascar, Mauritius and Mafia).Conclusions/SignificanceThe individual B. nasutus on Pemba infected with S. haematobium demonstrates that B. nasutus could also play a role in the local transmission of S. haematobium. We provide preliminary evidence that intraspecific variability of S. haematobium on Pemba may increase the transmission potential of S. haematobium locally due to the expanded intermediate host range, and that the presence of S. bovis complicates the environmental surveillance of schistosome infections.  相似文献   

17.

Background and Methods

Polyploidy results in genetic turmoil, much of which is associated with new phenotypes that result in speciation. Five independent lines of synthetic allotetraploid N. × obtusiata (N × o) were created from crosses between the diploid N. attenuata (Na) (♂) and N. obtusifolia (No) (♀) and the autotetraploids of Na (NaT) and No (NoT) were synthesized. Their genetic, genomic and phenotypic changes were then compared with those of the parental diploid species (Na and No) as well as to the natural allotetraploids, N. quadrivalvis (Nq) and N. clevelandii (Nc), which formed 1 million years ago from crosses between ancient Na and No.

Key Results

DNA fingerprinting profiles (by UP-PCR) revealed that the five N × o lines shared similar but not identical profiles. Both synthetic and natural polyploidy showed a dosage effect on genome size (as measured in seeds); however, only Nq was associated with a genome upsizing. Phenotypic analysis revealed that at the cellular level, N × o lines had phenotypes intermediate of the parental phenotypes. Both allo- and autotetraploidization had a dosage effect on seed and dry biomass (except for NaT), but not on stalk height at first flower. Nc showed paternal (Na) cellular phenotypes but inherited maternal (No) biomass and seed mass, whereas Nq showed maternal (No) cellular phenotypes but inherited paternal (Na) biomass and seed mass patterns. Principal component analysis grouped Nq with N × o lines, due to similar seed mass, stalk height and genome size. These traits separated Nc, No and Na from Nq and N × o lines, whereas biomass distinguished Na from N × o and Nq lines, and NaT clustered closer to Nq and N × o lines than to Na.

Conclusions

Both allo- and autotetraploidy induce considerable morphological, genetic and genomic changes, many of which are retained by at least one of the natural polyploids. It is proposed that both natural and synthetic polyploids are well suited for studying the evolution of adaptive responses.Key words: Nicotiana, polyploidy, genome size, DNA fingerprinting, phenotypic variation, Solanaceae  相似文献   

18.
Alfred C. Lenz 《Geobios》1978,11(5):623-653
Llandoverian and Wenlockian graptolite zonesin northern and Arctic Canada comprise the Sakmaricus-Laqueus Zone of latest Llandoverian age, Centrifugus Zone of earliest Wenlockian age, Rigidus Zone of about mid-Wenlockian age, possibly the Perneri Zone of late Wenlockian age, and the Testis-Lundgreni Zone of very late Wenlockian age.Species of Cyrtograptus described and illustratedin this study are C. centrifugus, C. cf. insectus, C. aff. lapworthi, C. laqueus, C. lundgreni, C. sp. (aff. C. lundgreni), C. mancki, C. radians, C. rigidus, C. sakmaricus, C. solaris n. subsp.? and C. sp. (similar to C. murchisoni bohemicus). Other taxa comprise Monograptus cf. capillaceus, M.? aff. deubeli, Gothograptus nassa, Plectograptus praemacilentus, Spinograptus cf. spinosus and Retiolites nevadensis.  相似文献   

19.
Glutathione S-transferases (GSTs) play a pivotal role in detoxifying endogenous and xenobiotic compounds and oxidative stress resistance in cells. In this study, five GST genes, including three Sigma GSTs (SlGSTs1, SlGSTs2, and SlGSTs3), one Omega GST (SlGSTo1) and one un-classified GST (SlGSTu1) were identified from the midgut of the Common cutworm, Spodoptera litura. Structure analyses of the eight (including the previously identified Epsilon GST genes, SlGSTe1, SlGSTe2 and SlGSTe3 from the same insect) SlGSTs genes showed that the Epsilon SlGSTe genes do not contain any intron, while the Sigma SlGSTs contain three introns and the Omega SlGSTo1 and the un-classified SlGSTu1 contain five introns. Analysis of the spatial and temporal expression of these eight SlGSTs indicated that SlGSTe1, SlGSTs2 and SlGSTo1 expressed in all stages of development from the egg to the adult stages. SlGSTe2, SlGSTe3, SlGSTs1, SlGSTs3 and SlGSTu1 had higher expression levels in the larval stages than in other stages and their expression levels in the midgut were higher than in other tissues. SlGSTs1 was expressed in the larval midgut but not in the fat body and could be induced by bacterial infections. The expression of SlGSTe1, SlGSTe3, SlGSTs1 and SlGSTs3 was increased by chlorpyrifos to various degrees, while the expression of SlGSTe1, SlGSTe3, SlGSTs1, SlGSTs3 and SlGSTo1 was increased by xanthotoxin. Levels of malonaldehyde, an indicator of oxidative stress, were higher in the larval midgut than in the pupal midgut. Chlorpyrifos induced the malonaldehyde content in the larvae, whereas xanthotoxin did not. It is hypothesized that high expression levels of the midgut SlGSTs might be due to the increased levels of oxidative stress caused by feeding, bacterial infection and xenobiotic compounds.  相似文献   

20.

Background

Several studies have identified multiple obesity-associated loci mainly in European populations. However, their contribution to obesity in other ethnicities such as Mexicans is largely unknown. The aim of this study was to examine 26 obesity-associated single-nucleotide polymorphisms (SNP) in a sample of Mexican mestizos.

Methods

9 SNPs in biological candidate genes showing replications (PPARG, ADRB3, ADRB2, LEPR, GNB3, UCP3, ADIPOQ, UCP2, and NR3C1), and 17 SNPs in or near genes associated with obesity in first, second and third wave GWAS (INSIG2, FTO, MC4R, TMEM18, FAIM2/BCDIN3, BDNF, SH2B1, GNPDA2, NEGR1, KCTD15, SEC16B/RASAL2, NPC1, SFRF10/ETV5, MAF, PRL, MTCH2, and PTER) were genotyped in 1,156 unrelated Mexican-Mestizos including 683 cases (441 obese class I/II and 242 obese class III) and 473 normal-weight controls. In a second stage we selected 12 of the SNPs showing nominal associations with obesity, to seek associations with quantitative obesity-related traits in 3 cohorts including 1,218 Mexican Mestizo children, 945 Mexican Mestizo adults, and 543 Indigenous Mexican adults.

Results

After adjusting for age, sex and admixture, significant associations with obesity were found for 6 genes in the case-control study (ADIPOQ, FTO, TMEM18, INSIG2, FAIM2/BCDIN3 and BDNF). In addition, SH2B1 was associated only with class I/II obesity and MC4R only with class III obesity. SNPs located at or near FAIM2/BCDIN3, TMEM18, INSIG2, GNPDA2 and SEC16B/RASAL2 were significantly associated with BMI and/or WC in the combined analysis of Mexican-mestizo children and adults, and FTO locus was significantly associated with increased BMI in Indigenous Mexican populations.

Conclusions

Our findings replicate the association of 8 obesity-related SNPs with obesity risk in Mexican adults, and confirm the role of some of these SNPs in BMI in Mexican adults and children.  相似文献   

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