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1.
Nat Commun ; 15(1): 4588, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816433

RESUMO

Lycibarbarspermidines are unusual phenolamide glycosides characterized by a dicaffeoylspermidine core with multiple glycosyl substitutions, and serve as a major class of bioactive ingredients in the wolfberry. So far, little is known about the enzymatic basis of the glycosylation of phenolamides including dicaffeoylspermidine. Here, we identify five lycibarbarspermidine glycosyltransferases, LbUGT1-5, which are the first phenolamide-type glycosyltransferases and catalyze regioselective glycosylation of dicaffeoylspermidines to form structurally diverse lycibarbarspermidines in wolfberry. Notably, LbUGT3 acts as a distinctive enzyme that catalyzes a tandem sugar transfer to the ortho-dihydroxy group on the caffeoyl moiety to form the unusual ortho-diglucosylated product, while LbUGT1 accurately discriminates caffeoyl and dihydrocaffeoyl groups to catalyze a site-selective sugar transfer. Crystal structure analysis of the complexes of LbUGT1 and LbUGT3 with UDP, combined with molecular dynamics simulations, revealed the structural basis of the difference in glycosylation selectivity between LbUGT1 and LbUGT3. Site-directed mutagenesis illuminates a conserved tyrosine residue (Y389 in LbUGT1 and Y390 in LbUGT3) in PSPG box that plays a crucial role in regulating the regioselectivity of LbUGT1 and LbUGT3. Our study thus sheds light on the enzymatic underpinnings of the chemical diversity of lycibarbarspermidines in wolfberry, and expands the repertoire of glycosyltransferases in nature.


Assuntos
Glicosiltransferases , Lycium , Glicosiltransferases/metabolismo , Glicosiltransferases/química , Glicosiltransferases/genética , Glicosilação , Lycium/enzimologia , Lycium/metabolismo , Lycium/química , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Glicosídeos/metabolismo , Glicosídeos/química , Cristalografia por Raios X , Piperidinas/metabolismo , Piperidinas/química , Especificidade por Substrato
2.
Microbiol Spectr ; 11(6): e0313923, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37930041

RESUMO

IMPORTANCE: Parasitoid wasp populations have developed persistent beneficial symbiotic relationships with several viruses through repeated evolution. However, there have been limited reports on RNA viruses in parasitoid wasps of tephritid flies, a significant pest group affecting fruits and vegetables. This study explores the diversity of RNA viruses in three parasitoid wasps of tephritid flies and highlights the potential biological significance of specific viruses in Diachasmimorpha longicaudata. These findings have important implications for the development of sustainable pest management strategies and the enhancement of artificial rearing techniques for parasitoid wasps.


Assuntos
Dípteros , Vírus de RNA , Vírus , Vespas , Animais , Vespas/genética , Vírus de RNA/genética
3.
Obesity (Silver Spring) ; 30(7): 1357-1369, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35707874

RESUMO

OBJECTIVE: This study aimed to recapitulate the change trajectory of postoperative weight and investigate the association between postoperative hypothalamic damage and weight gain and hypothalamic obesity (HO) in patients with adult-onset craniopharyngioma. METHODS: The data of 96 patients with surgically treated primary adult-onset craniopharyngioma were retrospectively analyzed. The association between postoperative hypothalamic damage based on magnetic resonance images or endoscopic observation and postoperative weight gain and HO was determined by multivariable logistic regression. RESULTS: Forty-seven (49.0%) patients and 18 (18.8%) patients experienced clinically meaningful weight gain (≥5%) and HO at last follow-up, respectively. Postoperative weight significantly increased during the first 6 months following surgery, followed by stabilization. Both grade 2 postoperative hypothalamus damage, as evaluated by the magnetic resonance imaging classification system of Müller et al., and higher scores based on the Roth et al. hypothalamic lesion score were significantly associated with postoperative weight gain of ≥5% (p = 0.005 and p = 0.002) and with HO (p = 0.001 and p = 0.008). Additionally, bilateral hypothalamic injury as evaluated by the Hong et al. hypothalamic injury pattern based on endoscopic observation (p = 0.008) could predict postoperative weight gain ≥5%. CONCLUSIONS: Significant postoperative weight gain is common in patients with adult-onset craniopharyngioma. Postoperative hypothalamic damage can predict clinically meaningful weight gain and HO.


Assuntos
Craniofaringioma , Doenças Hipotalâmicas , Neoplasias Hipofisárias , Adulto , Índice de Massa Corporal , Craniofaringioma/complicações , Craniofaringioma/diagnóstico por imagem , Craniofaringioma/cirurgia , Humanos , Doenças Hipotalâmicas/complicações , Hipotálamo/diagnóstico por imagem , Hipotálamo/patologia , Obesidade/complicações , Obesidade/patologia , Obesidade/cirurgia , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Aumento de Peso
4.
Front Oncol ; 11: 689943, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249739

RESUMO

BACKGROUND: It is well known that the clivus is composed of abundant cancellous bone and is often invaded by pituitary adenoma (PA), but the range of these cancellous bone corridors is unknown. In addition, we found that PA with clivus invasion is sometimes accompanied by petrous apex invasion, so we speculated that the petrous apex tumor originated from the clivus cancellous bone corridor. The aim of this study was to test this hypothesis by investigating the bony anatomy associated with PA with clival invasion and its clinical significance. METHODS: Twenty-two cadaveric heads were used in the anatomical study to research the bony architecture of the clivus and petrous apex, including six injected specimens for microsurgical dissection and sixteen cadavers for epoxy sheet plastination. The surgical videos and outcomes of PA with clival invasion in our single center were also retrospectively reviewed. RESULTS: The hypoglossal canal and internal acoustic meatus are composed of bone canals surrounded by cortical bone. The cancellous corridor within clivus starts from the sellar or sphenoid sinus floor and extends downward, bypassing the hypoglossal canal and finally reaching the occipital condyle and the medial edge of the jugular foramen. Interestingly, we found that the cancellous bone of the clivus was connected with that of the petrous apex through petroclival fissure extending to the medial margin of the internal acoustic meatus instead of a separating cortical bone between them as it should be. It is satisfactory that the anatomical outcomes of the cancellous corridor and the path of PA with clival invasion observed intraoperatively are completely consistent. In the retrospective cohort of 49 PA patients, the clival component was completely resected in 44 (89.8%), and only five (10.2%) patients in the early-stage had partial residual cases in the inferior clivus. CONCLUSION: The petrous apex invasion of PA is caused by the tumor invading the clivus and crossing the petroclival fissure along the cancellous bone corridor. PA invade the clivus along the cancellous bone corridor and can also cross the hypoglossal canal to the occipital condyle. This clival invasion pattern presented here deepens our understanding of the invasive characteristics of PA.

5.
Nat Commun ; 9(1): 1838, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743477

RESUMO

Furanosteroids, represented by wortmannin, viridin, and demethoxyviridin, are a special group of fungal-derived, highly oxygenated steroids featured by an extra furan ring. They are well-known nanomolar-potency inhibitors of phosphatidylinositol 3-kinase and widely used in biological studies. Despite their importance, the biosyntheses of these molecules are poorly understood. Here, we report the identification of the biosynthetic gene cluster for demethoxyviridin, consisting of 19 genes, and among them 15 biosynthetic genes, including six cytochrome P450 monooxygenase genes, are deleted. As a result, 14 biosynthetic intermediates are isolated, and the biosynthetic pathway for demethoxyviridin is elucidated. Notably, the pregnane side-chain cleavage requires three enzymes: flavin-dependent Baeyer-Villiger monooxygenase, esterase, and dehydrogenase, in sharp contrast to the single cytochrome P450-mediated process in mammalian cells. Structure-activity analyses of these obtained biosynthetic intermediates reveal that the 3-keto group, the C1ß-OH, and the aromatic ring C are important for the inhibition of phosphatidylinositol 3-kinase.


Assuntos
Androstenos/metabolismo , Pregnanos/metabolismo , Xylariales/metabolismo , Androstenos/química , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Vias Biossintéticas , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Pregnanos/química , Xylariales/enzimologia , Xylariales/genética
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