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1.
Inorg Chem ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483609

RESUMO

A nonstoichiometric ternary antimonide, Zr3.55Pt4Sb4, with a new structure type (hP24), has been synthesized via arc-melting. Its crystal structure was determined by single-crystal X-ray diffraction with hexagonal space group P63/mmc and lattice parameters a = 4.391(3) Å, c = 30.53(2) Å, and V = 509.7(8) Å3. It features the unique Pt4Sb4 slab with Pt-Pt bonds and is reminiscent to hexagonal diamond substructures. Three different Zr atoms, occupying three different sites, aid in the close-packing of the Pt and Sb atoms. Electronic structure calculations show the half occupancy of one Zr site creates a pseudogap at the Fermi level and optimizes the Pt-Sb bonding interactions. This enhances the electronic stability and accounts for the very narrow phase width observed for this nonstoichiometric compound. Furthermore, strong Zr-Pt and Zr-Sb interactions play a crucial role in the chemical bonding of the title compound. Electrical transport measurements show metallic behavior of this compound down to 2 K, consistent with the band structure calculations.

2.
Cell Reprogram ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31479283

RESUMO

Pig-induced pluripotent stem cells (piPSCs) have great potential application in regenerative medicine. The miR-302s cluster alone has been shown to reprogram mouse and human somatic cells into induced pluripotent stem cells (iPSCs) without exogenous transcription factors. However, miR-302s alone have not been reported to reprogram cells in large livestock. In this study, we induced pig somatic cells into partially reprogrammed piPSCs using overexpression of the miR-302s cluster (miR-302s-piPSC) and investigated the early reprogramming events during the miRNA induction process. The results showed that miR-302s-piPSCs exhibited some characteristics of pluripotent stem cells including expression of pluripotency markers-particularly, efficient activation of endogenous OCT4-and differentiation to the three germ layers in vitro. During the early reprogramming process, somatic cells first underwent epithelial-mesenchymal transition and then mesenchymal-epithelial transition to eventually form miR-302s-piPSCs. These data show, for the first time, that single factor miR-302s successfully induced pig somatic cells into miR-302s-piPSCs. This study provides a new tool and research direction for the induction of pluripotent stem cells in a large livestock.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31480153

RESUMO

Objective: Caseins and fatty acids of milk are synthesized and secreted by the epithelial cells of the mammary gland. All-trans retinoic acid (ATRA), an active metabolite of vitamin A, has been shown to promote mammary development. This study was conducted to determine the effect of ATRA on casein synthesis and fatty acid composition in MAC-T cells. Methods: MAC-T cells were allowed to differentiate for 4 d, treated with ATRA (0, 1.0, 1.5, and 2.0 µM), and incubated for 3 d. We analyzed the fatty acid composition, the mRNA expression of casein and fatty acid synthesis-related genes, and the phosphorylation of casein synthesis-related proteins of MAC-T cells by gas chromatography, qPCR, and western blotting, respectively. Results: In MAC-T cells, ATRA increased the mRNA levels of αS1-casein and ß-casein, janus kinase 2 (JAK2) and E74-like factor 5 (ELF5) of the signal transducer and activator of transcription 5 ß (STAT5-ß) pathway, ribosomal protein S6 kinase beta-1 (S6K1) and eukaryotic translation initiation factor 4E binding protein 1 (4EBP1) of the mammalian target of rapamycin (mTOR) pathway, inhibited the mRNA expression of phosphoinositide 3-kinase (PI3K) and eukaryotic initiation factor 4E (eIF4E) of the mTOR pathway, and promoted the phosphorylation of STAT5-ß and S6K1 proteins. Additionally, ATRA increased the de novo synthesis of fatty acids, reduced the content of long-chain fatty acids, the ratio of monounsaturated fatty acids (MUFA) to saturated fatty acids (SFA), the ratio of polyunsaturated fatty acids (PUFA) to SFA, and the ratio of ω-6 to ω-3 PUFA. The mRNA levels of acetyl-CoA carboxylase 1, fatty acid synthase, lipoprotein lipase, stearoyl-CoA desaturase (SCD), peroxisome proliferator-activated receptor gamma (PPARγ), and sterol regulatory element-binding protein 1 (SREBP1) were enhanced by ATRA. Conclusion: ATRA promotes the synthesis of casein by regulating JAK2/STAT5 pathway and downstream mTOR signaling pathway, and it improves the fatty acid composition of MAC-T cells by regulating SREBP1-related genes.

4.
Chem Commun (Camb) ; 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31475261

RESUMO

An unprecedented use of inexpensive organohalides as halogen electrophiles to trap the zwitterion intermediates generated from amines and arynes has been developed to access structurally diverse tertiary 2-haloanilines. Effective organohalides include carbon tetrachloride, hexachloroethane, N-chlorosuccinimide, carbon tetrabromide, fluorotribromomethane, N-bromosuccinimide, carbon tetraiodide, and N-iodosuccinimide.

5.
Biomark Med ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31497992

RESUMO

Aim: This study was to evaluate whether CO2CP level in venous blood could predict prognosis of patients with colorectal cancer (CRC). Materials & methods: A retrospective cohort of 238 patients with CRC who received surgical resection and 176 CRC Stage IV patients were included. A total of 114 healthy people were recruited as control. CO2CP levels were obtained from medical records. Survival analysis was performed to evaluate CO2CP predictive potential. The patients were divided into CO2CP high or low group based on CO2CP optimal cut-off values. Conclusion: The decreased CO2CP in CRC patients was associated with advanced clinical stage, and suggested that decreased CO2CP may predict the worse outcomes of disease-free survival in II/III stage CRC patients.

6.
Int J Biol Macromol ; 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31505211

RESUMO

Alicella gigantea (Alicelloidae) is a scavenger with the largest body size among amphipods. It is a participant in the foodweb of deepsea ecosystem and distributed with vast bathymetric and geographic ranges. In this study, the mitochondrial genome of A. gigantea was completely assembled and characterized. The complete sequence has a total length of 16,851 bp, comprising the usual eukaryotic components, with 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and 2 noncoding control regions (CRs). The gene rearrangement and reverse nucleotide strand bias of its mitochondrial genome are similar to those observed in the deepsea amphipod Eurythenes maldoror (Eurytheneidae), but different from the characters of Halice sp. MT-2017 (Dexaminoidea), an inhabitant of a deeper environment. Phylogenetic analysis indicates that A. gigantea occupies the basal branch of deepsea species-E. maldoror and Hirondellea gigas. This phylogeny supports the hypothesis that the evolution of hadal amphipods has undergone a transition from the abyssal depth. Compared to 41 available shallow water equivalents, the four accessible mitochondrial genomes from the deep sea, including the one produced in this study, show significantly fewer charged amino acids in the 13 PCGs, which suggests an adaption to the deepsea environment.

7.
Sci China Life Sci ; 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31515730

RESUMO

Urine-derived stem cells (USCs) have shown potentials for the treatment of skeletal and urological disorders. Based on published literature and our own data, USCs consist of heterogeneous populations of cells. In this paper, we identify and characterize two morphologically distinct subpopulations of USCs from human urine samples, named as spindle-shaped USCs (SS-USCs) and rice-shaped USCs (RS-USCs) respectively. The two subpopulations showed similar clone-forming efficiency, while SS-USCs featured faster proliferation, higher motility, and greater potential for osteogenic and adipogenic differentiation, RS-USCs showed greater potential for chondrogenic differentiation. POU5F1 was strongly expressed in both subpopulations, but MYC was weakly expressed. Both subpopulations showed similar patterns of CD24, CD29, CD34, CD44, CD73, CD90 and CD105 expression, while a higher percentage of RS-USCs were positive for CD133. SS-USCs were positive for VIM, weakly positive for SLC12A1 and UMOD, and negative for KRT18, NPHS1, AQP1 and AQP2, indicating a renal mesenchyme origin; while RS-USCs are positive for VIM, partially positive for KRT18, NPHS1, AQP1, SLC12A1 and UMOD, and negative for AQP2, indicating a nephron tubule origin. The above results can facilitate understanding of the biological characteristics of subpopulations of USCs, and provide a basis for further research and applications of such cells.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31513743

RESUMO

Solar-driven interfacial water evaporation is regarded as an effective, renewable, and environment-friendly technology for clean water production. However, bio-fouling caused by the nonspecific interaction between the steam generator and bio-foulants, generally hinders the efficient application of wastewater treatment. Herein, this work reports a facile strategy to fabricate flexible anti-biofouling fibrous photothermal membrane consisting of MXene coated cellulose membrane for efficient solar driven water steam generation toward water purification applications. The as-prepared MXene/cellulose photothermal membrane exhibits light absorption efficiency as high as ~94% in a wide solar spectrum range and a water evaporation rate up to 1.44 kg/m-2 h-1 under one solar illumination. Also, the MXene/cellulose membrane shows very high antibacterial efficiency (above 99.9%) owing to the MXene coating as a highly effective bacteriostatic agent. Such a flexible, anti-biofouling and high-efficiency photothermal membrane sheds light on practical applications in long-term wastewater treatments.

9.
Aging (Albany NY) ; 112019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31514170

RESUMO

Background: Aging has often been linked to age-related vascular disorders. The elucidation of the putative genes and pathways underlying vascular aging likely provides useful insights into vascular diseases at advanced ages. Transcriptional regulatory network analysis is the key to describing genetic interactions between molecular regulators and their target gene transcriptionally changed during vascular aging.Results: A total of 469 differentially expressed genes were parsed into 6 modules. Among the incorporated sample traits, the most significant module related to vascular aging was associated with triglyceride and enriched with biological terms like proteolysis, blood circulation, and circulatory system process. The module associated with triglyceride was preserved in an independent microarray dataset, indicating the robustness of the identified vascular aging-related subnetwork. Additionally, Enpp5, Fez1, Kif1a, F3, H2-Q7, and their interacting miRNAs mmu-miR-449a, mmu-miR-449c, mmu-miR-34c, mmu-miR-34b-5p, mmu-miR-15a, and mmu-let-7, exhibited the most connectivity with external lipid-related traits. Transcriptional alterations of the hub genes Enpp5, Fez1, Kif1a, and F3, and the interacting microRNAs mmu-miR-34c, mmu-miR-34b-5p, mmu-let-7, mmu-miR-449a, and mmu-miR-449c were confirmed.Conclusion: Our findings demonstrate that triglyceride and free fatty acid-related genes are key regulators of age-related vascular dysfunction in mice and show that the hub genes for Enpp5, Fez1, Kif1a, and F3 as well as their interacting miRNAs mmu-miR-34c, mmu-miR-34b-5p, mmu-let-7, mmu-miR-449a, and mmu-miR-449c, could serve as potential biomarkers in vascular aging.Methods: The microarray gene expression profiles of aorta samples from 6-month old mice (n=6) and 20-month old mice (n=6) were processed to identify nominal differentially expressed genes. These nominal differentially expressed genes were subjected to a weighted gene co-expression network analysis. A network-driven integrative analysis with microRNAs and transcription factors was performed to define significant modules and underlying regulatory pathways associated with vascular aging, and module preservation test was conducted to validate the age-related modules based on an independent microarray gene expression dataset in mice aorta samples including three 32-week old wild-type mice (around 6-month old) and three 78-week old wild-type mice (around 20-month old). Gene ontology and protein-protein interaction analyses were conducted to determine the hub genes as potential biomarkers in the progress of vascular aging. The hub genes were further validated with quantitative real-time polymerase chain reaction in aorta samples from 20 young (6-month old) mice and 20 old (20-month old) mice.

10.
Math Biosci Eng ; 16(5): 5672-5686, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31499731

RESUMO

Obstructive sleep apnea (OSA) is a common sleep-related respiratory disease that affects people's health, especially in the elderly. In the traditional PSG-based OSA detection, people's sleep may be disturbed, meanwhile the electrode slices are easily to fall off. In this paper, we study a sleep apnea detection method based on non-contact mattress, which can detect OSA accurately without disturbing sleep. Piezoelectric ceramics sensors are used to capture pressure changes in the chest and abdomen of the human body. Then heart rate and respiratory rate are extracted from impulse waveforms and respiratory waveforms that converted by filtering and processing of the pressure signals. Finally, the Heart Rate Variability (HRV) is obtained by processing the obtained heartbeat signals. The features of the heartbeat interval signal and the respiratory signal are extracted over a fixed length of time, wherein a classification model is used to predict whether sleep apnea will occur during this time interval. Model fusion technology is adopted to improve the detection accuracy of sleep apnea. Results show that the proposed algorithm can be used as an effective method to detect OSA.

11.
Mater Sci Eng C Mater Biol Appl ; 104: 109935, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31500057

RESUMO

The slow degradation of Fe severely restricts its application in bone repair although it possesses good biocompatibility and high mechanical properties. In this study, carbon nanotubes (CNTs) were introduced to accelerate Fe biodegradation: (I) CNTs acted as cathodes to induce galvanic corrosion owing to their differences in corrosion potential; (II) The large specific surface area of CNTs increased area ratios of cathode to anode; (III) The excellent electrical conductivity of CNTs allowed significant levels of electron transfer through the cathode in galvanic corrosion. Consequently, the degradation rate of Fe/CNTs composites greatly increased by 74% with the increase of CNTs (0.3-0.9 wt%). Further addition of CNTs would lead to corrosion holes and cracks due to localized corrosion. Besides, cell culture experiments showed that MG-63 cells could normally proliferate to maintain their population, indicating good cytocompatibility of Fe/CNTs composites. The results proved that the incorporation of CNTs into Fe was an effective approach to develop Fe-based bone implants with enhanced degradation rates.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31501329

RESUMO

Aminoacyl-transfer RNA (tRNA) synthetases (aaRSs) are the largest protein family causatively linked to neurodegenerative Charcot-Marie-Tooth (CMT) disease. Dominant mutations cause the disease, and studies of CMT disease-causing mutant glycyl-tRNA synthetase (GlyRS) and tyrosyl-tRNA synthetase (TyrRS) showed their mutations create neomorphic structures consistent with a gain-of-function mechanism. In contrast, based on a haploid yeast model, loss of aminoacylation function was reported for CMT disease mutants in histidyl-tRNA synthetase (HisRS). However, neither that nor prior work of any CMT disease-causing aaRS investigated the aminoacylation status of tRNAs in the cellular milieu of actual patients. Using an assay that interrogated aminoacylation levels in patient cells, we investigated a HisRS-linked CMT disease family with the most severe disease phenotype. Strikingly, no difference in charged tRNA levels between normal and diseased family members was found. In confirmation, recombinant versions of 4 other HisRS CMT disease-causing mutants showed no correlation between activity loss in vitro and severity of phenotype in vivo. Indeed, a mutation having the most detrimental impact on activity was associated with a mild disease phenotype. In further work, using 3 independent biophysical analyses, structural opening (relaxation) of mutant HisRSs at the dimer interface best correlated with disease severity. In fact, the HisRS mutation in the severely afflicted patient family caused the largest degree of structural relaxation. These data suggest that HisRS-linked CMT disease arises from open conformation-induced mechanisms distinct from loss of aminoacylation.

13.
Opt Express ; 27(15): 20694-20703, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510158

RESUMO

A novel quintuplet spectrum is observed in  3He atoms' metastable state 23S1, when linear polarized light is adopted to probe the alignment component of its F=3/2 hyperfine structure. Static and oscillating magnetic fields produce magnetic resonance and Rabi nutation in ground state 11S0, respectively. After Fourier transform, centre frequency of the metastable-state quintuplet spectrum coincidences with the ground state Larmor frequency, and frequency separations between the five peaks equal to that of ground state Rabi nutation. Similar quintuplet spectrum is observed in  4He metastable state mixed with  3He hybrid vapor.

14.
Opt Express ; 27(16): 23476-23485, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510624

RESUMO

Recent experimental research has reported that a surface electric field on the polymer solar cell can restrain the recombination of the resultant charged carriers [23]. Based on this, this article reveals an underlying mechanism: If a surface electric field below 4.5 × 104 V/cm is applied to the polymer layer, the electric field drives the charged polaron to transport. Once the polaron approaches and collides with the exciton, it is easily trapped by the potential well produced by the exciton and then forms a charged exciton. The decay of the resultant charged exciton rapidly reduces the number of excitons. However, once the external field surpasses the threshold value of 4.5 × 104 V/cm, the charged polaron absorbs momentum from the external electric field and shakes off the trapping of the exciton. It finally steps out of the original lattice potential well, where the appropriate electric field magnitude ranges from 5.5 × 104 V/cm to 8 × 105 V/cm. After a collision of 300 fs, apart from a phase shift, the exciton still exists. Then, the originally carriers is dissociated when the electric field reaches 0.8 MV/cm. The applied surface field is able to effectively keep the excitons from fusion with the transporting charged polarons, which provides a valid and easily manufactured approach to yield higher efficiency of polymer solar cells.

15.
Endocr J ; 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391353

RESUMO

To study the thyroid regeneration and injury of recurrent laryngeal nerve after irreversible electroporation (IRE). 12 pigs were divided into three groups: six pigs underwent IRE, other pigs were used as controls. IRE was performed near tracheoesophageal groove, to ablate most part of thyroid gland. Parathyroid and thyroid function, recurrent laryngeal nerve injury and thyroid computed tomography (CT) imaging were regularly investigated. The histopathology results were analyzed to detect thyroid regeneration. Masson's trichrome method for collagen and immunohistochemistry were performed for Soluble protein-100 (S100) and neurofilaments on nerve section. In IRE group, there were no symptoms of recurrent laryngeal nerve-related injury. No abnormalities of recurrent laryngeal nerve were shown on hematoxylin-eosin (HE) staining, Masson's trichrome staining, Neurofilament (NF) staining and S100 staining. There were no significant changes for thyroid and parathyroid function in all pigs. Immediately after IRE, CT showed hypoattenuation in the ablated thyroid gland and it became swelling. 14 days after IRE, thyroid CT showed hetergenous attenuation in the electroporation zone, and the size and attenuation of thyroid gland were normal after two months. There was cell apoptosis in the thyroid gland after IRE. Seven and 14 days after IRE, there was fragmentation of nucleus within the follicle, and some follicles were empty. Two months later, complete regeneration of thyroid tissue was shown. IRE was shown to be both effective and safe with complete regeneration of thyroid tissue and preservation of the function and structure of the recurrent laryngeal nerve.

16.
World J Gastroenterol ; 25(29): 3956-3971, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31413530

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a common chronic non-organic disease of the digestive system. Berberine (BBR) has been used to treat patients with IBS, but the underlying therapeutic mechanism is little understood. We believe that BBR achieves its therapeutic effect on IBS by preventing stress intestinal inflammation and visceral hypersensitivity and reducing bowel motility. AIM: To test the hypothesis that BBR achieves its therapeutic effect on IBS by preventing subclinical inflammation of the intestinal mucosa and reducing visceral hypersensitivity and intestinal motility. METHODS: IBS was induced in rats via water avoidance stress (WAS). qRT-PCR and histological analyses were used to evaluate the levels of cytokines and mucosal inflammation, respectively. Modified ELISA and qRT-PCR were used to evaluate the nuclear factor kappa-B (NF-κB) signal transduction pathway. Colorectal distention test, gastrointestinal transit measurement, Western blot, and qRT-PCR were used to analyze visceral sensitivity, intestinal motility, the expression of C-kit (marker of Cajal mesenchymal cells), and the expression of brain derived neurotrophic factor (BDNF) and its receptor TrkB. RESULTS: WAS led to mucosal inflammation, visceral hyperalgesia, and high intestinal motility. Oral administration of BBR inhibited the NF-κB signal transduction pathway, reduced the expression of pro-inflammatory cytokines [interleukin (IL)-1ß, IL-6, interferon-γ, and tumor necrosis factor-α], promoted the expression of anti-inflammatory cytokines (IL-10 and transforming growth factor-ß), and improved the terminal ileum tissue inflammation. BBR inhibited the expression of BDNF, TrkB, and C-kit in IBS rats, leading to the reduction of intestinal motility and visceral hypersensitivity. The therapeutic effect of BBR at a high dose (100 mg/kg) was superior to than that of the low-dose (25 mg/kg) group. CONCLUSION: BBR reduces intestinal mucosal inflammation by inhibiting the intestinal NF-κB signal pathway in the IBS rats. BBR reduces the expression of BDNF, its receptor TrkB, and C-kit. BBR also reduces intestinal motility and visceral sensitivity to achieve its therapeutic effect on IBS.

17.
J Exp Med ; 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467036

RESUMO

The NLRP3 inflammasome is critical for EAE pathogenesis; however, the role of gasdermin D (GSDMD), a newly identified pyroptosis executioner downstream of NLRP3 inflammasome, in EAE has not been well defined. Here, we observed that the levels of GSDMD protein were greatly enhanced in the CNS of EAE mice, especially near the areas surrounding blood vessels. GSDMD was required for the pathogenesis of EAE, and GSDMD deficiency in peripheral myeloid cells impaired the infiltration of immune cells into the CNS, leading to the suppression of neuroinflammation and demyelination. Furthermore, the loss of GSDMD reduced the activation and differentiation of T cell in the secondary lymphoid organs and prevented T cell infiltration into CNS of EAE. The administration of inflammasome-related cytokines partially rescued the impairment of pathogenesis of EAE in GSDMD KO mice. Collectively, these findings provide the first demonstration of GSDMD in peripheral myeloid cells driving neuroinflammation during EAE pathogenesis.

18.
BMJ ; 366: l4555, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467132
19.
East Mediterr Health J ; 25(6): 374-384, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31469157

RESUMO

Background: Among low- and middle-income nations, the highest prevalence of child overweight and associated metabolic disorders has been found in Middle Eastern and Eastern European countries. Obesity has been on the rise in Turkey and past research has shown regional variations among adults. However, the prevalence of childhood obesity in different socioeconomic groups in the largest metropolitan areas in the country has not been reported. Aims: This study aimed to investigate the prevalence of child obesity with a population-representative, SES-stratified random sample with objective measures of body mass index (BMI) in the capital city of Turkey. Methods: Weight status was measured by the WHO growth curve and analyzed by socioeconomic status (SES), sex, and parental factors in a population-representative sample of 2066 parent-child dyads. Chi-square and logistic regression were conducted. Results: Rates of overweight and obesity were 21.2% and 14.6% (35.8% combined) but significantly higher in high (24.5% and 18.9%) vs. low SES (20.1% and 13.8%) (P = 0.02). Boys were at higher risk for obesity than girls, especially in high vs. low SES (Odds Ratio [OR] = 3.0 [95% CI: 1.4-6.5] vs. 1.7 [95% CI: 1.2-2.5]). Having both parents being overweight or obese increased the risk for obesity, particularly in medium and high SES (OR = 5.8 [95% CI: 2.3-14.1]) and 6.3 (95% CI: 1.5-26.2). Conclusions: Higher maternal education was a risk factor in low-to-medium but not high SES. In Ankara, child overweight and obesity appears to be 1.5 times more prevalent than national estimates. Higher SES may signify greater exposure to an obesogenic environment and greater obesity risk.

20.
Insect Biochem Mol Biol ; 113: 103210, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31422152

RESUMO

Insect cytochrome P450 monooxygenases (CYPs) play essential roles in both xenobiotic metabolism and developmental processes. However, the exact physiological function of many CYP genes remains largely unknown. Screening the expression of the CYP genes from the CYP2 and mitochondrial CYP clans of Drosophila melanogaster revealed that Cyp303a1 is highly expressed in the pupal stage. Knockdown of CYP303A1 transcripts by RNAi using the Gal4/UAS system with a ubiquitous driver (tubulin-Gal4) in Drosophila or by dsRNA injection in the last nymph stage of Locusta migratoria resulted in severe defects in eclosion and lethality during and after adult emergence. In Drosophila, tissue-specific RNAi of Cyp303a1 with a wing-specific driver (MS1096-Gal4) revealed that Cyp303a1 was essential for wing extension. Stage-specific RNAi of Cyp303a1 using Gal80ts for thermal-dependent-suppression found that the expression of Cyp303a1 at the middle pupal stage was absolutely required. Meanwhile, Cyp303a1 mutants exhibited more than 80% lethality at the late embryonic development stages. Embryonic lethality of the Cyp303a1 mutants was fully rescued by the ubiquitous overexpression of exogenous Cyp303a1. Taken together, we conclude that Cyp303a1 is indispensable for embryonic development and adult eclosion in D. melanogaster, the latter role being conserved over 400 million years of insect evolution.

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