Seok Ho Yoon, and Taijoon ChungMol. Cells 2019; 42(4): 285-291 https://doi.org/10.14348/molcells.2019.0011
Abstract : Eukaryotic cells use conserved quality control mechanisms to repair or degrade defective proteins, which are synthesized at a high rate during proteotoxic stress. Quality control mechanisms include molecular chaperones, the ubiquitin-proteasome system, and autophagic machinery. Recent research reveals that during autophagy, membrane-bound organelles are selectively sequestered and degraded. Selective autophagy is also critical for the clearance of excess or damaged protein complexes (e.g., proteasomes and ribosomes) and membrane-less compartments (e.g., protein aggregates and ribonucleoprotein granules). As sessile organisms, plants rely on quality control mechanisms for their adaptation to fluctuating environments. In this mini-review, we highlight recent work elucidating the roles of selective autophagy in the quality control of proteins and RNA in plant cells. Emphasis will be placed on selective degradation of membrane-less compartments and protein complexes in the cytoplasm. We also propose possible mechanisms by which defective proteins are selectively recognized by autophagic machinery.
Jeongmin Park, Yeonsoo Joe, Stefan W. Ryter, Young-Joon Surh, and Hun Taeg ChungMol. Cells 2019; 42(4): 292-300 https://doi.org/10.14348/molcells.2019.0016
Abstract : Immunometabolism, defined as the interaction of metabolic pathways with the immune system, influences the pathogenesis of metabolic diseases. Metformin and carbon monoxide (CO) are two pharmacological agents known to ameliorate metabolic disorders. There are notable similarities and differences in the reported effects of metformin and CO on immunometabolism. Metformin, an anti-diabetes drug, has positive effects on metabolism and can exert anti-inflammatory and anti-cancer effects
Hwajung Ri, Jongbin Lee, Jun Young Sonn, Eunseok Yoo, Chunghun Lim, and Joonho ChoeMol. Cells 2019; 42(4): 301-312 https://doi.org/10.14348/molcells.2019.2451
Abstract : Post-transcriptional regulation underlies the circadian control of gene expression and animal behaviors. However, the role of mRNA surveillance via the nonsense-mediated mRNA decay (NMD) pathway in circadian rhythms remains elusive. Here, we report that
Jisun Jung, Charles D. Surh, and You Jeong LeeMol. Cells 2019; 42(4): 313-320 https://doi.org/10.14348/molcells.2019.2431
Abstract : Intraepithelial lymphocytes (IELs) develop through the continuous interaction with intestinal antigens such as commensal microbiome and diet. However, their respective roles and mutual interactions in the development of IELs are largely unknown. Here, we showed that dietary antigens regulate the development of the majority of CD8αβ IELs in the small intestine and the absence of commensal microbiota particularly during the weaning period, delay the development of IELs. When we tested specific dietary components, such as wheat or combined corn, soybean and yeast, they were dependent on commensal bacteria for the timely development of diet-induced CD8αβ IELs. In addition, supplementation of intestinal antigens later in life was inefficient for the full induction of CD8αβ IELs. Overall, our findings suggest that early exposure to commensal bacteria is important for the proper development of dietary antigen-dependent immune repertoire in the gut.
Lishi Yang, Junyang Li, Shaozhi Fu, Peirong Ren, Juan Tang, Na Wang, Xiangxiang Shi, Jingbo Wu, and Sheng LinMol. Cells 2019; 42(4): 321-332 https://doi.org/10.14348/molcells.2019.2441
Abstract : The brain is the most common metastatic site of lung adenocarcinoma; however, the mechanism of this selective metastasis remains unclear. We aimed to verify the hypothesis that exposure of tumor cells to the brain microenvironment leads to changes in their gene expression, which promotes their oriented transfer to the brain. A549 and H1299 lung adenocarcinoma cells were exposed to human astrocyte-conditioned medium to simulate the brain microenvironment. Microarray analysis was used to identify differentially expressed genes, which were confirmed by quantitative real-time PCR and western blotting. Knockdown experiments using microRNAs and the overexpression of genes by cell transfection were performed in addition to migration and invasion assays.
Dong-Yeop Kim, Woo Jin Kim, Jung-Hyun Kim, Seok-Ho Hong, and Sun Shim ChoiMol. Cells 2019; 42(4): 333-344 https://doi.org/10.14348/molcells.2019.2442
Abstract : Various genetic and environmental factors are known to be associated with chronic obstructive pulmonary disease (COPD). We identified COPD-related differentially expressed genes (DEGs) using 189 samples accompanying either adenocarcinoma (AC) or squamous cell carcinoma (SC), comprising 91 normal and 98 COPD samples. DEGs were obtained from the intersection of two DEG sets separately identified for AC and SC to exclude the influence of different cancer backgrounds co-occurring with COPD. We also measured patient samples named group ‘I’, which were unable to be determined as normal or COPD based on alterations in gene expression. The Gene Ontology (GO) analysis revealed significant alterations in the expression of genes categorized with the ‘cell adhesion’, ‘inflammatory response’, and ‘mitochondrial functions’, i.e., well-known functions related to COPD, in samples from patients with COPD. Multi-omics data were subsequently integrated to decipher the upstream regulatory changes linked to the gene expression alterations in COPD. COPD-associated expression quantitative trait loci (eQTLs) were located at the upstream regulatory regions of 96 DEGs. Additionally, 45 previously identified COPD-related miRNAs were predicted to target 66 of the DEGs. The eQTLs and miRNAs might affect the expression of ‘respiratory electron transport chain’ genes and ‘cell proliferation’ genes, respectively, while both eQTLs and miRNAs might affect the expression of ‘apoptosis’ genes. We think that our present study will contribute to our understanding of the molecular etiology of COPD accompanying lung cancer.
Jong-Yeup Kim, Min-Ji Cha, Young-Seon Park, Jaeku Kang, Jong-Joong Choi, Seung Min In, and Dong-Kyu KimMol. Cells 2019; 42(4): 345-355 https://doi.org/10.14348/molcells.2019.2418
Abstract : Eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP) is one of the most challenging problems in clinical rhinology. FZD5 is a receptor for Wnt5A, and its complex with Wnt5A contributes to activating inflammation and tissue modification. Nasal polyps and eosinophil/non-eosinophil counts are reported to be directly correlated. This study investigated the expression and distribution of FZD5, and the role of eosinophil infiltration and FZD5 in eosinophilic CRSwNP pathogenesis. The prognostic role of eosinophil levels was evaluated in seven patients with CRSwNP. Fifteen patients with CRS were classified based on the percentage of eosinophils in nasal polyp tissue. Methylated genes were detected using methyl-CpG-binding domain sequencing, and qRT-PCR and immunohistochemistry were used to detect FZD5 expression in nasal polyp tissue samples. The results showed that mRNA expression of FZD5 was upregulated in nasal polyps. FZD5 expression was significantly higher in nasal polyp samples from patients with eosinophilic CRSwNP than in those from patients with non-eosinophilic CRSwNP, as indicated by immunohistochemistry. Furthermore, inflammatory cytokine levels were higher in eosinophilic CRSwNP-derived epithelial cells than in normal tissues. In conclusion, FZD5 expression in nasal mucosal epithelial cells is correlated with inflammatory cells and might play a role in the pathogenesis of eosinophilic CRSwNP.
Songhee H. Kim, Melissa Vieira, Hye-Jin Kim, Mahipal Singh Kesawat, and Hye Yoon ParkMol. Cells 2019; 42(4): 356-362 https://doi.org/10.14348/molcells.2019.2398
Abstract : The binding of MS2 bacteriophage coat protein (MCP) to MS2 binding site (MBS) RNA stem-loop sequences has been widely used to label mRNA for live-cell imaging at single-molecule resolution. However, concerns have been raised recently from studies with budding yeast showing aberrant mRNA metabolism following the MS2-GFP labeling. To investigate the degradation pattern of MS2-GFP-labeled mRNA in mammalian cells and tissues, we used Northern blot analysis of β-actin mRNA extracted from the
Jeesun Chun, Kum-Kang So, Yo-Han Ko, Jung-Mi Kim, and Dae-Hyuk KimMol. Cells 2019; 42(4): 363-375 https://doi.org/10.14348/molcells.2019.0019
Abstract : Fungal sectorization is a complex trait that is still not fully understood. The unique phenotypic changes in sporadic sectorization in mutants of
Zhongwei Wang, Wei Mei, Qingde Wang, Rundong Guo, Peilin Liu, Yuqiang Wang, Zijuan Zhang, and Limin WangMol. Cells 2019; 42(4): 376-376 https://doi.org/10.14348/molcells.2019.1028