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Biology subjects

liu, t.

Publications and source records attributed to liu, t..

4 recordsLinked to original sources

Non-planar perylene diimides dual-targeting mitochondrial membrane potential and mitochondrial DNA transcription for an-titumor Therapy

Mitochondrial DNA (mtDNA) transcription is an emerging target in cancer therapy. While enzyme-targeted inhibitors such as IMT1B block POLRMT, their organelle specificity remains unclear. Here, we report a distinct strategy using non-planar perylene diimide derivatives (PDIs). The fluorescent lead compound PDIC-BL combines mitochondrial membrane potential ({Delta}{Psi}m) dependent accumulation (validated in cells and isolated mitochondria), and with direct intercalation into mtDNA (Kd = 32 M), as demonstrated by single-molecule stretching assays. This dual-targeting mechanism leads to selective inhibition of mitochondrial transcription, ROS generation and triggers apoptosis. PDIC-BL exhibits superior antitumor efficacy in breast cancer cell lines (MCF-7, MDA-MB-231) and significantly supresses tumor growth in vivo, with good tolerability in cancer xenograft model in nude mice. This work not only elucidates the structure-activity relationship of non-planar PDIs, but also offers a generalizable strategy for developing organelle-selective DNA binding therapeutics.

cancer biology↗

Allantoin induces pruritus by activating MrgprD in chronic kidney disease

Chronic kidney disease is a disease with decreased, irreversible renal function. Pruritus is the most common skin symptom in patients with chronic kidney disease, especially in end-stage renal disease (AKA chronic kidney disease-associated pruritus [CKD-aP]); however, the underlying molecular and neural mechanism of the CKD-aP in patients remains obscure. Our data show that the level of allantoin increases in the serum of CKD-aP and CKD model mice. Allantoin could induce scratching behavior in mice and active DRG neurons; the calcium influx and the action potential were significantly reduced in DRG neurons of MrgprD KO or TRPV1 KO mice. U73122, an antagonist of PLC, could also block calcium influx in DRG neurons induced by allantoin. Thus, our results concluded that allantoin plays an important role in CKD-aP, mediated by MrgprD and TrpV1, in CKD patients.

pathology↗

Bioinformatics analysis of endophytic bacteria related to berberine in the Chinese medicinal plant Coptis teeta Wall.

Plant endophytic microorganisms absorb nutrients and prevent pathogen damage, supporting healthy plant growth. However, relationships between endophytic bacteria of the medicinal plant Coptis teeta Wall. and berberine production remain unclear. Herein, we explored the microbial composition of wild-type (WT) and cultivated Coptis teeta Wall. root, stem and leaf, and endophytic bacteria related to berberine. Microbial characteristics of were analyzed by 16S rDNA sequencing, and berberine in roots was analyzed by high-performance liquid chromatography (HPLC). Proteobacteria, Actinobacteria and Bacteroidetes were the major phyla, and Mycobacterium, Salmonella, Nocardioides, Burkholderia-Paraburkholderia and Rhizobium were the dominant genera. Berberine was positively correlated with total P (TP), total N (TN), total K (TK) and available K (AK) in rhizosphere soil, and with Microbacterium and norank_f_7B-8, whereas TK was positively correlated with Microbacterium, TN, AK and Burkholderia-Paraburkholderia. The findings will support further studies on endophytic bacteria and berberine in Coptis teeta Wall., and may promote berberine production.

microbiology↗

Biolistic transformation of Haematococcus pluvialis with constructs based on the flanking sequences of its endogenous alpha tubulin gene

The complete sequence information of the alpha tubulin (tub) genes was obtained from both Haematococcus pluvialis NIES144 and SCCAP K0084., Putative transcriptional elements and polyadenylation signals were identified respectively in their 5 and 3 flanking regions. Three selection cassettes of tub/aadA, tub/hyr and tub/ble with 3 different antibiotic-resistant genes fused between the 5 and 3 flanking sequences of the tub gene were constructed and utilized for biolistic transformation of H.pluvialis. Antibiotic resistant transformants were obtained in the bombardments with the tub/aadA cassette in 2 strains. It was found that, the foreign tub/aadA DNA could be completely transferred and inherited in their genome through non-homologous recombination. Moreover, transcripts of the insert and spectinomycin resistance were identified. Transformation efficiencies up to 3x10-5 per g DNA could be obtained in H.pluvialis NIES144 or SCCAP K0084 through utilization of a culture with a high percentage of flagellate cells and by optimizing bombarding protocol. The presented selection marker and optimized transforming procedures in this report should strengthen the platform technology for genetical manipulation and modification of H.pluvialis.

molecular biology↗