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1.
Nat Commun ; 15(1): 4877, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849342

RESUMO

In flowering plants, the predominant sexual morph is hermaphroditism, and the emergence of unisexuality is poorly understood. Using Cucumis melo (melon) as a model system, we explore the mechanisms driving sexual forms. We identify a spontaneous mutant exhibiting a transition from bisexual to unisexual male flower, and identify the causal mutation as a Harbinger transposon impairing the expression of Ethylene Insensitive 2 (CmEIN2) gene. Genetics and transcriptomic analysis reveal a dual role of CmEIN2 in both sex determination and fruit shape formation. Upon expression of CmACS11, EIN2 is recruited to repress the expression of the carpel inhibitor, CmWIP1. Subsequently, EIN2 is recruited to mediate stamina inhibition. Following the sex determination phase, EIN2 promotes fruit shape elongation. Genome-wide analysis reveals that Harbinger transposon mobilization is triggered by environmental cues, and integrates preferentially in active chromatin, particularly within promoter regions. Characterization of a large collection of melon germplasm points to active transpositions in the wild, compared to cultivated accessions. Our study underscores the association between chromatin dynamics and the temporal aspects of mobile genetic element insertions, providing valuable insights into plant adaptation and crop genome evolution.


Assuntos
Elementos de DNA Transponíveis , Etilenos , Flores , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Elementos de DNA Transponíveis/genética , Etilenos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Transdução de Sinais/genética , Cucumis melo/genética , Cucumis melo/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Mutação
2.
Int J Mol Sci ; 24(13)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37446368

RESUMO

Melon is a recalcitrant plant for stable genetic transformation. Various protocols have been tried to improve melon transformation efficiency; however, it remains significantly low compared to other plants such as tomato. In this study, the primary focus was on the optimization of key parameters during the inoculation and co-culture steps of the genetic transformation protocol. Our results showed that immersing the explants in the inoculation medium for 20 min significantly enhanced transformation efficiency. During the co-culture step, the use of filer paper, 10 mM 2-(N-morpholino)-ethanesulfonic acid (MES), and a temperature of 24 °C significantly enhanced the melon transformation efficiency. Furthermore, the impact of different ethylene inhibitors and absorbers on the transformation efficiency of various melon varieties was explored. Our findings revealed that the use of these compounds led to a significant improvement in the transformation efficiency of the tested melon varieties. Subsequently, using our improved protocol and reporter-gene construct, diploid transgenic melons successfully generated. The efficiency of plant genetic transformation ranged from 3.73 to 4.83%. Expanding the scope of our investigation, the optimized protocol was applied to generate stable gene-edited melon lines using the Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated cytosine base editor and obtained melon lines with editions (C-to-T and C-to-G) in the eukaryotic translation initiation factor 4E, CmeIF4E gene. In conclusion, the optimized melon transformation protocol, along with the utilization of the CRISPR/Cas9-mediated cytosine base editor, provides a reliable framework for functional gene engineering in melon. These advancements hold significant promise for furthering genetic research and facilitating crop improvement in this economically important plant species.


Assuntos
Cucumis melo , Cucurbitaceae , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Cucumis melo/genética , Cucurbitaceae/genética , Plantas/genética
3.
Sci Rep ; 12(1): 15038, 2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36057728

RESUMO

Effect of a range of t-butyl perbenzoates bearing electron-withdrawing and electron-donating substitutions on the phenyl ring and HZSM-5 as a porous additive at 0 °C in enantioselective allylic C-H bond oxidation of cyclic and acyclic olefins in the presence of Cu (I)-(S,aS,S) complexes of biphenyl bisoxazoline ligands, produced easily through the chelation-induced process, were investigated. The enantioenriched allylic esters were obtained in reasonable times with excellent enantioselectivities and yields using electron-withdrawing substituted peresters in the presence of Cu (I)-(S,aS,S)-1a complex, containing phenyl groups at the stereogenic centers of the oxazoline moieties. To reach a better insight on geometry, chemical activity, enantioselectivity, and thermodynamic stability of the Cu (I)-BOX complexes, DFT calculations with B3LYP-D3/6-31G (d, p) level of theory were applied to them. Moreover, NBO analysis was used to illustrate interactions between orbitals.

4.
J Mol Graph Model ; 108: 107986, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34303179

RESUMO

This study focused on the theoretical viability of Ngn@C24N24 (Ng = Ne, Ar, Kr, Xe, and Rn; n = 1, 2) complexes using density functional theory at the computational level of ωB97X-D/def2-TZVP. Thermodynamic and kinetic stabilities of these complexes have been evaluated by calculating the interaction energy of Ng atoms encapsulated C24N24 cage (ΔEint), and the corresponding dissociation energy barrier (ΔG‡), respectively. The obtained results predict that although these complexes are thermodynamically unstable compared to their dissociation into free Ng atoms and the bare C24N24 cage, but once formed, they are protected by the activation energy barrier of the corresponding dissociation process. Furthermore, natural population analysis (NPA) and topological analysis of the electron density have been employed to investigate the nature of Ng-Ng and Ng-cage interactions. The results demonstrate that these interactions are highly significant compared to similar cases in the free state; and the amounts of energy of the interaction gradually increases as the Ng atom becomes heavier. Surprisingly in the Kr2@C24N24 complex the Kr-Kr bond is somewhat covalent in nature relative to non-bonded interaction in Kr2 free dimer.


Assuntos
Fulerenos , Porfirinas , Porosidade , Termodinâmica
5.
Iran J Public Health ; 49(7): 1348-1354, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33083302

RESUMO

BACKGROUND: The head louse infestation is a public health issue in the world especially, affecting most people who live in camps, school-aged children and their families. Head lice treatment has economic ramifications that often under calculated. The aim of this study was evaluation of economic burden associated with head louse infestation in Iran. METHODS: In a cross-sectional study, 500,002 infestations were diagnosed among suspected head lice infested people who referred to health care system in all provinces of Iran during 2017. Direct and indirect costs related to paid by patients and government systems were extracted by referring to accounting documents and interviews with patients and experts and were recorded in researcher-made forms. Microsoft Excel 2010 software was used for economic burden calculation. RESULTS: The incidence rate of head lice infestation in Iran was 500,002/79,926,270 (625.5 per 100,000 populations). Economic burden of head lice in the country was calculated at 5,790,143$. Direct and indirect costs, governmental cost, out of pocket and total costs of head lice were included 3.14$, 2.84$, 5.98$, 5.60$ and 11.58$ per case respectively. CONCLUSION: The direct and indirect costs associated with treatment of infestations were relatively high. Therefore, the creation of medical facilities such as availability of diagnostic and treatment strategies can be effective in the control of infestation. The adoption of infestation prevention methods, such as health education to people at risk of infestation, reduces the incidence of head lice and imposition of related treatment costs on governmental health care system and head lice cases.

6.
J Phys Chem A ; 117(5): 939-46, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23360416

RESUMO

By taking the energy to be a Morse-like function of the number of electrons, E(N) = α{1 - e(-ß(N-δ))}(2) - κ, the electronic chemical potential and global hardness values for a set of atoms and some molecules are calculated from the accurate definitions of these two concepts and using the hybrid B3LYP functional and 6-311++G** basis set. By a comparison between the obtained hardnesses and the corresponding experimental values, it is found that the proposed model yields better values for hardnesses with respect to those that are obtained from the other frequently used methods. It is claimed that the difference between the calculated and experimental hardness values may arise from the approximate equation used for the evaluation of experimental hardnesses. Both of the calculated and experimental molecular hardnesses are used to investigate the change of hardness during the course of some exothermic reactions according to the maximum hardness principle (MHP). It is shown that the obtained hardnesses of reactions from the calculated hardnesses (Δη(calc)) are more successful in predicting the directions of these reactions than those that are evaluated from the experimental hardnesses (Δη(exp)).

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