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Ito, E.

Publications and source records attributed to Ito, E..

3 recordsLinked to original sources

Histone acetyltransferase activity of CREB-binding protein is essential for synaptic plasticity in Lymnaea

In eukaryotes, CREB-binding protein (CBP), a coactivator of CREB, functions both as a platform for recruiting other components of the transcriptional machinery and as a histone acetyltransferase (HAT) that alters chromatin structure. We previously showed that the transcriptional activity of cAMP-responsive element binding protein (CREB) plays a crucial role in neuronal plasticity in the pond snail Lymnaea stagnalis. However, there is no information on the role CBP plays in CREB-initiated plastic changes in Lymnaea. In this study, we characterized the Lymnaea CBP (LymCBP) gene and investigated the roles it plays in synaptic plasticity involved in regulating feeding behaviors. Similar to CBPs of other species, LymCBP possesses functional domains, such as KIX domain, which is essential for interaction with CREB and was shown to regulate long-term memory (LTM). In situ hybridization showed that the staining patterns of LymCBP mRNA in the central nervous system were very similar to those of Lymnaea CREB1 (LymCREB1). A particularly strong LymCBP mRNA signal was observed in the Cerebral Giant Cell (CGC), an identified extrinsic modulatory interneuron of the feeding circuit, key to both appetitive and aversive LTM for taste. Biochemical experiments using the recombinant protein of LymCBP HAT domain showed that its enzymatic activity was blocked by classical HAT inhibitors such as curcumin, anacardic acid and garcinol. Preincubation of Lymnaea CNSs with these HAT inhibitors blocked cAMP-induced long-term potentiation between the CGC and the follower B1 motoneuron. We therefore suggest that HAT activity of LymCBP in the CGCs is a key factor in synaptic plasticity contributing to LTM after classical conditioning.

neuroscience

Evaluation of the Efficacy and Safety of a Clinical Grade Human Induced Pluripotent Stem Cell-Derived Cardiomyocyte Patch: A Pre-Clinical Study

AimsCardiomyocyte-derived induced pluripotent stem cells (iPSCs) may represent a promising therapeutic strategy for severely damaged myocardium. This study aimed to assess the efficacy and safety of clinical grade human iPSC-derived cardiomyocyte (hiPSC-CM) patches and conduct a pre-clinical proof-of-concept analysis. Methods and resultsA clinical grade hiPSC line was established from peripheral blood mononuclear cells collected from a healthy volunteer homozygous for human leukocyte antigens and differentiated into cardiomyocytes using cytokines and chemical compounds. hiPSC-CMs were cultured on temperature-responsive culture dishes to fabricate the hiPSC-CM patch. The hiPSC-CMs expressed cardiomyocyte-specific genes and proteins while electrophysiological analyses revealed that hiPSC-CMs were similar to the human myocardium. In vitro safety studies using cell growth, soft agar colony formation, and undifferentiated cell assays indicated that tumourigenic cells were not present. Moreover, no genomic mutations were discovered using whole genome and exome sequencing analysis. Tumour formation was not detected in an in vivo tumourigenicity assay using NOG mice. General toxicity tests also showed no adverse events due to hiPSC-CM patch transplantation. An efficacy study using a porcine model of myocardial infarction demonstrated significantly improved cardiac function with angiogenesis and a reduction in interstitial fibrosis, which was enhanced by cytokine secretion from hiPSC-CM patches after transplantation. No lethal arrhythmias were observed. ConclusionhiPSC-CM patches show promise for future translational research and clinical trials for ischaemic heart failure. One-sentence summaryThis pre-clinical study provides a proof-of-concept of the safety and efficacy of hiPSC-CM patches for the treatment of heart failure. Translational PerspectiveRegenerative therapy using cells and tissues is attractive as a novel approach for treating severe heart failure. We focused on human iPS cell-derived cardiomyocytes (hiPSC-CMs) as a cell source. Using basic research, the characteristics of hiPSC, hiPSC-CMs, and hiPSC-CM patches were determined in vitro and in vivo. We also conducted a pre-clinical study using a porcine model of myocardial infarction that confirmed the safety and efficacy of the hiPSC-CM patch, highlighting its potential for clinical application.

cell biology

Oxicam-type NSAIDs enhance Agrobacterium-mediated transformation in plants

Agrobacterium-mediated transformation represents a key innovation for plant breeding and is routinely used in research and applied biology. However, for several species, the efficacy of transformation is limited. In this study, we discovered that oxicam-type nonsteroidal anti-inflammatory drugs (NSAIDs), including tenoxicam (TNX), enhance the efficiency of Agrobacterium-mediated transient transformation in the model species Arabidopsis thaliana via leaf infiltration and can be successfully applied in analyses of the subcellular localisation of fluorescent fusion proteins. TNX acts as an inhibitor of plant immune responses and lacks similar transient transformation efficiency in a dde2/ein2/pad4/sid2 quadruple mutant background, thereby indicating that TNX increases the efficiency of Agrobacterium infection via a transient shutdown of the immune system mediated by jasmonic acid, ethylene, and salicylic acid signalling. In addition, we found that TNX enhances the efficiency of stable transformation in crops of agricultural and economic importance, such as Jatropha and maize, indicating that TNX can enhance the integration of exogenous DNA into the plant genome via an increased introduction of DNA into plant cells. Given that treatment with oxicam compounds is simple, cost effective, and has broad utility, we anticipate that this discovery will contribute to accelerating genome-editing technologies in plants.

plant biology