Search Results (3)

Bolting and flowering time are critical agronomic traits affecting the commercial value and breeding efficiency of Chinese cabbage (Brassica rapa L. ssp. pekinensis). Although vernalization is a key environmental signal promoting flowering, its regulatory mechanisms remain poorly understood in this crop. Here, we identify the flowering repressor gene BrMAF5 and its antisense long non-coding RNA BrMAF5L as negative regulators of vernalization-induced flowering. During vernalization, transcript levels of both genes showed a decreasing trend as the vernalization period extended. Functional assays in Arabidopsis thaliana demonstrated that ectopic expression of BrMAF5 or BrMAF5L significantly delayed flowering, accompanied by increased expression of floral repressors (AtFLC, AtTEM1) and reduced expression of floral activators (AtFT, AtSOC1). Moreover, protein interaction analysis revealed that BrMAF5 associates with BrACP4 and BrRAB1A, linking it to fatty acid metabolism and membrane trafficking pathways. Collectively, our results reveal a novel regulatory module in vernalization-mediated flowering. These findings pave the way for developing bolting-resistant Brassicaceae crops by identifying promising molecular targets. Full article

Zeolitic imidazolate frameworks MAF-5 and MAF-6 based on Zn²⁺ and 2-ethylimidazole were demonstrated to be efficient heterogeneous catalysts in solvent-free coupling of CO₂ and propylene oxide (PO) to produce propylene carbonate (PC) at 0.8 MPa of CO₂ and 80 °C. Activity of MAF-5 was lower in comparison with MAF-6 due to the difference in their structural and textural characteristics. MAF-6 samples with particle size of 190 ± 20, 360 ± 30, and 810 ± 30 nm were prepared at room temperature from [Zn(NH₃)₄](OH)₂ and 2-ethylimidazole. Control of particle size was achieved by variation of type of alcohol in alcohol/cyclohexane media for the preparation of MAF-6. According to this comprehensive study, the yield of PC was found to decrease with increasing crystal size of the MAF-6 material, which was related to the change in textural properties and the number and localization of active sites. The combination of MAF-6 with particle size of with particle size of 190 ± 20 nm and tetrabutylammonium bromide ([n-Bu₄N]Br) as co-catalyst led to an approximately 4-fold enhancement in the yield of PC (80.5%). Compared with reported ZIFs catalysts, the efficiencies of MAF-5/[n-Bu₄N]Br and MAF-6/[n-Bu₄N]Br binary systems were comparable and higher under similar reaction conditions. Full article

A considerable number of estrogen receptor-positive breast cancer (ER⁺ BrCa) patients develop resistance to endocrine treatment. One of the most important resistance mechanisms is the presence of ESR1 mutations. We developed and analytically validated a highly sensitive and specific NaME-PrO-assisted ARMS (NAPA) assay for the detection of four ESR1 mutations (Y537S, Y537C, Y537N and D538G) in circulating tumour cells (CTCs) and paired plasma circulating tumour DNA (ctDNA) in patients with ER⁺ BrCa. The analytical specificity, analytical sensitivity and reproducibility of the assay were validated using synthetic oligos standards. We further applied the developed ESR1 NAPA assay in 13 ER⁺ BrCa primary tumour tissues, 13 non-cancerous breast tissues (mammoplasties) and 64 liquid biopsy samples: 32 EpCAM-positive cell fractions and 32 paired plasma ctDNA samples obtained at different time points from 8 ER+ metastatic breast cancer patients, during a 5-year follow-up period. Peripheral blood from 11 healthy donors (HD) was used as a control. The developed assay is highly sensitive (a detection of mutation-allelic-frequency (MAF) of 0.5% for D538G and 0.1% for Y537S, Y537C, Y537N), and highly specific (0/13 mammoplasties and 0/11 HD for all mutations). In the plasma ctDNA, ESR1 mutations were not identified at the baseline, whereas the D538G mutation was detected in five sequential ctDNA samples during the follow-up period in the same patient. In the EpCAM-isolated cell fractions, only the Y537C mutation was detected in one patient sample at the baseline. A direct comparison of the ESR1 NAPA assay with the drop-off ddPCR using 32 identical plasma ctDNA samples gave a concordance of 90.6%. We present a low cost, highly specific, sensitive and robust assay for blood-based ESR1 profiling. The clinical performance of the ESR1 NAPA assay will be prospectively evaluated in a large number of well-characterized patient cohorts. Full article