Madin-Darby canine kidney (MDCK) cells are the recognized cell strain for influenza vaccine production. However, the tumorigenic potential of MDCK cells raises concerns about their use in biological product manufacturing. To reduce MDCK cells' tumorigenicity and ensure the safety of influenza vaccine production, a B-cell lymphoma extra-large (Bcl-xL) gene, which plays a pivotal role in apoptosis regulation, was knocked-out in original MDCK cells by CRISPR-Cas9 gene editing technology, so that a homozygous MDCK-Bcl-xL-/- cell strain was acquired and named as BY-02.
View Article and Find Full Text PDFThe hippocampus is broadly impacted by neuromodulations. However, how neuropeptides shape the function of the hippocampus and the related spatial learning and memory remains unclear. Here, we discover the crucial role of cholecystokinin (CCK) in heterosynaptic neuromodulation from the medial entorhinal cortex (MEC) to the hippocampus.
View Article and Find Full Text PDFCoxsackievirus A5 (CV-A5) is a re-emerging enterovirus that causes hand, foot, and mouth disease in children under five years of age. CV-A5-M14-611 is a mouse-adapted strain that can infect orally and lead to the death of 14-day-old mice. Here, recombinants based on CV-A5-M14-611 were constructed carrying three reporter genes in different lengths.
View Article and Find Full Text PDFHuman induced pluripotent stem cells (iPSC) can be used to understand the pathological mechanisms of human disease. These cells are a promising source for cell-replacement therapy. However, such studies require genetically defined conditions.
View Article and Find Full Text PDFGlycosylphosphatidylinositol-anchored HDL-binding protein (GPIHBP1) binds both LPL and chylomicrons, suggesting that GPIHBP1 is a platform for LPL-dependent processing of triglyceride (TG)-rich lipoproteins. Here, we investigated whether GPIHBP1 affects LPL activity in the absence and presence of LPL inhibitors angiopoietin-like (ANGPTL)3 and ANGPTL4. Like heparin, GPIHBP1 stabilized but did not activate LPL.
View Article and Find Full Text PDFBacteriophage lambda N and bacterial Nus proteins together with a unique site NUT in the leader of the early viral N gene transcript bind RNA polymerase (RNAP) and form a highly processive antitermination complex; N bound at NUT also represses N translation. In this study, we investigate whether N and NUT cause N translation repression as part of the antitermination complex by testing conditions that inhibit the formation of the N-modified transcription complex for their effect on N-mediated translation repression. We show that nus and nut mutations that in combination destabilize multiple interactions in the antitermination complex prevent N-mediated translation repression.
View Article and Find Full Text PDFThe bacteriophage lambda (lambda) recombination system Red has been used for engineering large DNA fragments cloned into P1 and bacterial artificial chromosomes (BAC or PAC) vectors. So far, this recombination system has been utilized by transferring the BAC or PAC clones into bacterial cells that harbor a defective lambda prophage. Here we describe the generation of a mini-lambda DNA that can provide the Red recombination functions and can be easily introduced by electroporation into any E.
View Article and Find Full Text PDFA phage lambda-based recombination system, Red, can be used for high-efficiency mutagenesis, repair, and engineering of chromosomal or episomal DNA in vivo in Escherichia coli. When long linear double-stranded DNA with short flanking homologies to their targets are used for the recombination, the lambda Exo, Beta, and Gam proteins are required. The current model is: (i) Gam inhibits the host RecBCD activity, thereby protecting the DNA substrate for recombination; (ii) Exo degrades from each DNA end in a 5' --> 3' direction, creating double-stranded DNA with 3' single-stranded DNA tails; and (iii) Beta binds these 3' overhangs to protect and anneal them to complementary sequences.
View Article and Find Full Text PDFEfficient expression of most bacteriophage lambda early genes depends upon the formation of an antiterminating transcription complex to overcome transcription terminators in the early operons, p(L) and p(R). Formation of this complex requires the phage-encoded protein N, the first gene product expressed from the p(L) operon. The N leader RNA contains, in this order: the NUTL site, an RNase III-sensitive hairpin and the N ribosome-binding site.
View Article and Find Full Text PDF