Genes to Cells最新文献

Drosophila melanogaster has provided numerous insights into the olfactory system, primarily relying on a series of transgenic Gal4 drivers. The combined use of Gal4/UAS and a second binary expression system, such as the QF/QUAS system, provides the opportunity to manipulate the two distinct cell populations, thereby accelerating the elucidation of the olfactory neural mechanisms. However, resources apart from the Gal4/UAS system have been poorly developed. In this study, we generated a series of odorant receptor (Or)-QF2 knock-in driver (Or-QF2^KI) lines for 23 Ors using the CRISPR/Cas9 knock-in method. In these lines, the QF2 protein is cotranslated with each Or product. The expression pattern of the Or-QF2^KI drivers mostly corresponded to that of the Or-Gal4 drivers. In addition, the Or42a-QF2^KI driver identified the additional expression pattern of Or42a, which is consistent with the data of single-nucleus RNA sequencing and is attributed to the Or-QF2^KI drivers' ability to reflect the endogenous expression of the Or genes. Thus, these Or-QF2^KI drivers can be used as valuable genetic tools for olfactory research in Drosophila.

Fibulin 2 (FBLN2) is an extracellular matrix glycoprotein. Exclusion of exon 9 of FBLN2 is one of the most recurrent splicing events across multiple types of cancer, but its functional relevance in cancer has remained unexplored. We here reveal that the exclusion of exon 9 of FBLN2 results in the loss of a single N-glycosylation site that leads to misfolding of the FBLN2 protein as well as to a reduction in both its stability and secretion efficiency. Indeed, the extracellular matrix of human colorectal cancer tissue exhibits a reduced abundance of FBLN2. This deficiency of FBLN2 together with a concomitant increase in the abundance of fibronectin 1 in the tumor microenvironment promotes the adhesion and migration of colorectal cancer cells. Our data thus suggest that the alternative splicing of FBLN2 exon 9 generates a prometastatic extracellular environment in cancer tissue by determining FBLN2 glycosylation.

In Drosophila males, the accessory gland is responsive to nutrient signal-dependent regulation of fertility/fecundity. The accessory gland is composed of two types of binucleated epithelial cells, about 1000 main cells and 60 secondary cells (SCs). The transcription factors Defective proventriculus (Dve), Abdominal-B, and Ecdysone receptors (EcRs) are strongly expressed in adult SCs. In response to nutrient conditions during development, coordinated action between Dve and ecdysone signaling determines the optimal number of SCs and regulates their maturation. A downstream effector of ecdysone signaling, Ftz-F1, is crucial in this process. Another downstream effector, Polished rice (Pri), is small peptides of 11 or 32 amino acids. Here we show that pri is required for maturation of SCs and for male fecundity, whereas it is not involved in determination of the number of SCs. We provide evidence that Pri acts downstream of Ftz-F1 to regulate maturation but not survival of SCs.

Calcium/calmodulin-dependent protein kinase IIδ (CaMKIIδ), encoded by the Camk2d gene, plays key regulatory roles in various Ca²⁺-regulated cellular processes. Extensive alternative splicing of the Camk2d gene generates multiple CaMKIIδ splice variants that exhibit differential roles. Despite significant advances in understanding the functions of CaMKIIδ, the full repertoire of Camk2d splice variants in a variety of tissues and their distinct roles in physiological and pathological contexts remain incompletely characterized due to the complex nature of multiple alternative splicing events. Here, we conducted long-read amplicon sequencing to investigate the murine Camk2d splice variants in the heart, skeletal muscle, and olfactory bulbs and show that mRNAs in the heart and skeletal muscle have shorter 3'UTRs. Our results in this study suggest that a key regulator of Camk2d splicing, RNA-binding motif protein 20 (RBM20), whose gain-of-function mutations cause dilated cardiomyopathy, is crucial for the expression of heart-specific splice variants. Olfactory bulbs specifically express novel splice variants that utilize a mutually exclusive exon 6B and/or an alternative polyadenylation site in a novel exon 17.5 in an RBM20-independent manner. The tissue-specific repertoire of CaMKIIδ splice variants and their aberrant expression in disease model animals will help in understanding their roles in physiological and pathological contexts.

Chromatin restructuring across multiple hierarchical scales directs lineage-specific gene expression during cell differentiation. Here, we investigated the iron-dependent demethylation of histone H3 lysine 9 dimethylation (H3K9me2) by the demethylase jumonji domain-containing 1A (JMJD1A) in adipocyte differentiation. Using the 3T3-L1 adipocyte differentiation model, we show that JMJD1A knockdown increases H3K9me2 levels, whereas forced expression of wild-type JMJD1A reduces H3K9me2 levels within the A compartment, as defined by megabase scale high-throughput chromosome conformation capture (Hi-C) data. In contrast, a JMJD1A mutant defective in iron coordination was unable to demethylate H3K9me2. Genome-wide analyses of H3K9me2 levels at transcription start sites on a kilobase scale demonstrated that JMJD1A targets genes involved in peroxisome proliferator-activated receptor signaling and lipid metabolism in an iron-dependent manner, supporting a model in which H3K9me2 demethylation facilitates adipogenic transcription networks. Furthermore, we examined the relationship between H3K9me2 and lamin B1 levels within lamina-associated domains (LADs) specifically reorganized during differentiation. Although LADs with higher H3K9me2 exhibited modestly elevated lamin B1 association in preadipocytes, lamin B1 levels declined during differentiation regardless of H3K9me2 status. These findings emphasize the importance of the iron-dependent enzymatic function in JMJD1A and broaden our understanding of how specific H3K9 demethylases coordinate compartmentalized epigenetic programs during adipogenesis.

Kohyanagi, N., and T. Ohama. 2023. “The Impact of SETBP1 Mutations in Neurological Diseases and Cancer.” Genes to Cells 28, no. 9: 629–641. https://doi.org/10.1111/gtc.13057.

We would like to sincerely thank the reader's comments regarding Table 1. After reviewing the suggestions, we have identified and acknowledged several inaccuracies in the original table listing SETBP1 variants.

We mistakenly described frameshift variants cited by Coe et al. (2014) as missense variants. We also incorrectly labeled the associated disease as Schinzel–Giedion syndrome (SGS) instead of intellectual disability (ID), which would have been appropriate.

We apologize for the oversight and any confusion or misinterpretation this may have caused.

In eukaryotic cells, genomic DNA is compacted by nucleosomes, as basic repeating units, into chromatin. The nucleosome arrangement in chromatin fibers could be an important determinant for chromatin folding, by which genomic DNA is regulated in the nucleus. To study the structures of chromatin units in cells, we have established a method for the structural analysis of native mono- and poly-nucleosomes prepared from HeLa cells. In this method, the chromatin in isolated nuclei was crosslinked to preserve the proximity information between nucleosomes, followed by chromatin fragmentation by micrococcal nuclease treatment. The mono- and poly-nucleosomes were then fractionated by sucrose gradient ultracentrifugation, and their structures were analyzed by cryo-electron microscopy. Cryo-electron microscopy single particle analysis and cryo-electron tomography visualized a native nucleosome structure and secondary nucleosome arrangements in cellular chromatin. This method provides a complementary strategy to fill the gap between in vitro and in situ analyses of chromatin structure.