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The long juvenile period of citrus trees (often more than 6 years) has hindered genetic improvement by traditional breeding methods and genetic studies. In this work, we have developed a biotechnology tool to promote transition from the vegetative to the reproductive phase in juvenile citrus plants by expression of the Arabidopsis thaliana or citrus FLOWERING LOCUS T (FT) genes using a Citrus leaf blotch virus‐based vector (clbvINpr‐AtFT and clbvINpr‐CiFT, respectively). Citrus plants of different genotypes graft inoculated with either of these vectors started flowering within 4–6 months, with no alteration of the plant architecture, leaf, flower or fruit morphology in comparison with noninoculated adult plants. The vector did not integrate in or recombine with the plant genome nor was it pollen or vector transmissible, albeit seed transmission at low rate was detected. The clbvINpr‐AtFT is very stable, and flowering was observed over a period of at least 5 years. Precocious flowering of juvenile citrus plants after vector infection provides a helpful and safe tool to dramatically speed up genetic studies and breeding programmes.  相似文献   
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Identifying the factors that affect a plant’s probability of being found and damaged by herbivores has been a central topic in the study of herbivory. Although herbivory could have important negative consequences on carnivorous plants, their interaction with herbivores remains largely unexplored. We evaluated the effect of spatial variation in light environment (sunny, shade and full-shade sites) on the pattern of leaf herbivory and florivory of the carnivorous plant Pinguicula moranensis. Plants’ overall probability of leaf damage was high (74.24%). Mean herbivory was four times higher in the sunny and shade sites than the observed in the full-shade site. Nearly 8% of plants suffered damage to reproductive structures, although the probability of florivory was similar among sites. Discussion addressed the inter-site variation in mean herbivory considering the effect of light exposure and the impact that herbivory could have on fitness components of this carnivorous plant.  相似文献   
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The establishment, remodeling and maintenance of tissular architecture during animal development, and even across juvenile to adult life, are deeply regulated by a delicate interplay of extracellular signals, cell membrane receptors and intracellular signal messengers. It is well known that cell adhesion molecules (cell-cell and cell-extracellular matrix) play a critical role in these processes. Particularly, adherens junctions (AJs) mediated by E-cadherin and catenins determine cell-cell contact survival and epithelia function. Consequently, this review seeks to encompass the complex and prolific knowledge about E-cadherin roles during physiological and pathological states, particularly focusing on the influence exerted by the thyroid hormone (TH).  相似文献   
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Polluted agricultural soils are a serious problem for food safety, with phytoremediation being the most favorable alternative from the environmental perspective. However, this methodology is generally time-consuming and requires the cessation of agriculture. Therefore, the purpose of this study was to evaluate two potential phytoextractor plants (the native species Bidens pilosa and Tagetes minuta) co-cropped with lettuce growing on agricultural lead-polluted soils. The concentrations of Pb, as well as of other metals, were investigated in the phytoextractors, crop species, and in soils, with the potential risk to the health of consumers being estimated. The soil parameters pH, EC, organic matter percentage and bioavailable lead showed a direct relationship with the accumulation of Pb in roots. In addition, the concentration of Pb in roots of native species was closely related to Fe (B. pilosa, r = 0.81; T. minuta r = 0.75), Cu (T. minuta, r = 0.93), Mn (B. pilosa, r = 0.89) and Zn (B. pilosa, r = 0.91; T. minuta, r = 0.91). Our results indicate that the interaction between rhizospheres increased the phytoextraction of lead, which was accompanied by an increase in the biomass of the phytoextractor species. However, the consumption of lettuce still revealed a toxicological risk from Pb in all treatments.  相似文献   
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Rectal cancer represents about 30% of colorectal cancers, being around 50% locally advanced at presentation. Chemoradiation (CRT) followed by total mesorectal excision is the standard of care for these locally advanced stages. However, it is not free of adverse effects and toxicity and the complete pathologic response rate is between 10% and 30%. This makes it extremely important to define factors that can predict response to this therapy. Focal adhesion kinase (FAK) expression has been correlated with worse prognosis in several tumours and its possible involvement in cancer radio‐ and chemosensitivity has been suggested; however, its role in rectal cancer has not been analysed yet. To analyse the association of FAK expression with tumour response to CRT in locally advanced rectal cancer. This study includes 73 patients with locally advanced rectal cancer receiving standard neoadjuvant CRT followed by total mesorectal excision. Focal adhesion kinase protein levels were immunohistochemically analysed in the pre‐treatment biopsies of these patients and correlated with tumour response to CRT and patients survival. Low FAK expression was significantly correlated with local and distant recurrence (P = 0.013). Low FAK expression was found to be a predictive marker of tumour response to neoadjuvant therapy (P = 0.007) and patients whose tumours did not express FAK showed a strong association with lower disease‐free survival (P = 0.01). Focal adhesion kinase expression predicts neoadjuvant CRT response in rectal cancer patients and it is a clinically relevant risk factor for local and distant recurrence.  相似文献   
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