Review
Biochemistry & Molecular Biology
Rina Fujiwara-Tani, Shiori Mori, Ruiko Ogata, Rika Sasaki, Ayaka Ikemoto, Shingo Kishi, Masuo Kondoh, Hiroki Kuniyasu
Summary: CLDN4 is a crucial component of tight junctions in epithelial cells and is overexpressed in many epithelial malignancies. Changes in CLDN4 expression are associated with epigenetic factors, inflammation, and growth factor signaling. CLDN4 plays a role in maintaining the tumor microenvironment and acts as a barrier to anticancer drug entry.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Microbiology
Keisuke Ohta, Naoki Saka, Masayoshi Fukasawa, Machiko Nishio
Summary: This study investigated the correlation between tight junctions and nairoviruses using Hazara orthonairovirus (HAZV) as a surrogate model for Crimean-Congo hemorrhagic fever virus. The results showed that HAZV infection induced the expression of tight junction proteins, especially claudin-1, and inhibited the cell-to-cell spread of HAZV. The HAZV nucleoprotein was found to bind to claudin-1 and negatively regulate its cell surface expression, promoting the cell-to-cell spread of HAZV.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Food Science & Technology
Yunika Mayangsari, Mayu Okudaira, Chinatsu Mano, Yuki Tanaka, Osamu Ueda, Tomohiro Sakuta, Yoshiharu Suzuki, Yoshinari Yamamoto, Takuya Suzuki
Summary: Research showed that DMF can enhance intestinal TJ barrier integrity by increasing the expression of occludin and claudin-1, while reducing the expression of claudin-2. This regulation involves the induction of occludin protein translation via mTOR and silencing Cldn2 mRNA via miR-16-5p.
JOURNAL OF FUNCTIONAL FOODS
(2021)
Article
Multidisciplinary Sciences
Koya Suzuki, Kosuke Yamaga, Reitaro Tokumasu, Tatsuya Katsuno, Hiroo Tanaka, Shuhei Chiba, Takeshi Yagi, Ichiro Katayama, Atsushi Tamura, Hiroyuki Murota, Sachiko Tsukita
Summary: Hair retention in infant mice is regulated by Claudin (CLDN)-1 and CLDN3, which maintain the appropriate layered architecture of hair follicles. Deficiencies in these proteins can lead to hair loss.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
Kumi Takasawa, Akira Takasawa, Taishi Akimoto, Kazufumi Magara, Tomoyuki Aoyama, Hiroshi Kitajima, Taro Murakami, Yusuke Ono, Daisuke Kyuno, Hiromu Suzuki, Makoto Osanai
Summary: The abnormal expression of claudin-1 in cervical adenocarcinoma cells not only affects conventional tight junction functions, but also influences the expression and activity of a wide range of proteins associated with cell adhesion and actin cytoskeleton remodeling, contributing to malignant potentials and microvilli formation.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
(2021)
Article
Virology
Kamilla Toon, Mphatso D. Kalemera, Machaela Palor, Nicola J. Rose, Yasuhiro Takeuchi, Joe Grove, Giada Mattiuzzo
Summary: Due to increased and broadened screening efforts, the number of viral species in the Hepacivirus genus has rapidly expanded. Genetic features of hepaciviruses suggest they have adapted and evolved to hijack host proteins for efficient liver propagation. A study on GB virus B (GBV-B) found that claudin-1 is an essential entry factor, shared with hepatitis C virus (HCV), but with distinct mechanisms of entry. Understanding the molecular mechanisms of hepacivirus entry can inform the design of new vaccines and treatments targeting the first stage of HCV infection.
JOURNAL OF VIROLOGY
(2023)
Article
Multidisciplinary Sciences
Kenta Shigetomi, Yumiko Ono, Kenji Matsuzawa, Junichi Ikenouchi
Summary: It has been found that cholesterol accumulation is essential for the formation of tight junctions, which are crucial for the epithelial barrier. Despite the absence of tight junctions, cholesterol still accumulates normally in the vicinity of the apical junctions. Moreover, a claudin mutant that cannot bind to Zonula Occludens (ZO) proteins can still form tight junction strands. ZO proteins are not only scaffolds for claudins, but also promote the formation of cholesterol-rich membrane domains at apical junctions through their effect on the junctional actomyosin cytoskeleton.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Gastroenterology & Hepatology
Natascha Roehlen, Marion Muller, Zeina Nehme, Emilie Crouchet, Frank Juhling, Fabio Del Zompo, Sara Cherradi, Francois H. T. Duong, Nuno Almeida, Antonio Saviano, Mirian Fernandez-Vaquero, Tobias Riedl, Houssein El Saghire, Sarah C. Durand, Clara Ponsolles, Marine A. Oudot, Romain Martin, Nicolas Brignon, Emanuele Felli, Patrick Pessaux, Antonin Lallement, Irwin Davidson, Simonetta Bandiera, Christine Thumann, Patrice Marchand, Solange Moll, Brandon Nicolay, Nabeel Bardeesy, Yujin Hoshida, Mathias Heikenwaelder, Roberto Iacone, Alberto Toso, Markus Meyer, Greg Elson, Tamas Schweighoffer, Geoffrey Teixeira, Mirjam B. Zeisel, Patrice Laquerriere, Joachim Lupberger, Catherine Schuster, Laurent Mailly, Thomas F. Baumert
Summary: In this study, the role of CLDN1 as a therapeutic target for hepatocellular carcinoma (HCC) was investigated using humanized monoclonal antibodies targeting non-junctional CLDN1 and various cell and animal models. The results demonstrated that targeting non-junctional CLDN1 significantly suppressed tumor growth and invasion, and affected tumor stemness, metabolism, oncogenic signaling, and the tumor immune microenvironment. These findings provide a rationale for targeting CLDN1 in the treatment of advanced HCC and lay the foundation for the development of CLDN1-specific monoclonal antibodies for clinical use.
JOURNAL OF HEPATOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Fumisato Maesaka, Masaomi Kuwada, Shohei Horii, Shingo Kishi, Rina Fujiwara-Tani, Shiori Mori, Kiyomu Fujii, Takuya Mori, Hitoshi Ohmori, Takuya Owari, Makito Miyake, Yasushi Nakai, Nobumichi Tanaka, Ujjal Kumar Bhawal, Yi Luo, Masuo Kondoh, Kiyohide Fujimoto, Hiroki Kuniyasu
Summary: In bladder urothelial carcinoma (BUC), the overexpression of CLDN4 is associated with cancer progression. Through analyzing BUC cases, it was found that hypomethylation of CLDN4 promoter DNA increases CLDN4 expression and promotes cell proliferation, stemness, and epithelial-mesenchymal transition. Treatment with demethylating agent AZA leads to excessive CLDN4 expression, specifically the TJ-unintegrated CLDN4 monomer. The TJ-unintegrated CLDN4 binds to integrin beta 1 and enhances stemness, drug resistance, and metastatic ability of the cells, as well as exhibits an anti-apoptosis effect via FAK phosphorylation.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Cell Biology
Hyunjhung Jhun, Won-Young Lee, Jin-Ki Park, Sun-Goo Hwang, Hyun-Jung Park
Summary: Cryptorchidism may affect Claudin expression, which in turn impacts the proliferation of Sertoli cells and spermatogenesis.
Article
Biochemistry & Molecular Biology
Abigail Taylor, Mark Warner, Christopher Mendoza, Calvin Memmott, Tom LeCheminant, Sara Bailey, Colter Christensen, Julie Keller, Arminda Suli, Dario Mizrachi
Summary: The tight junction (TJ) is a structure composed of multiple proteins responsible for cell-cell adhesion in polarized endothelium and epithelium. This article introduces a new experimental method to study the membrane protein claudins (CLDNs), providing a novel approach for studying other membrane proteins.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Medicine, Research & Experimental
Harleen Kaur, Regis Moreau
Summary: The role of mTORC1 in the regulation of intestinal barrier function and permeability remains to be fully elucidated.
Article
Multidisciplinary Sciences
Alex J. Vecchio, Sewwandi S. Rathnayake, Robert M. Stroud
Summary: The study reveals the molecular and structural basis of how CpE targets susceptible claudins, as well as differences in the primary CpE receptors in mice and humans due to sequence changes in the target motif.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Caroline Hempel, Rita Rosenthal, Anja Fromm, Susanne M. Krug, Michael Fromm, Dorothee Gunzel, Joerg Piontek
Summary: This study analyzed the structural and functional differences between claudin-15 and claudin-10b cation channels and identified several mutants that affect ion permeability and pore diameter. Furthermore, the study revealed that the charge at the W63/K64 position has an impact on the assembly and properties of claudin-10b channels but not claudin-15 channels.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
(2022)
Review
Multidisciplinary Sciences
Erika Wakayama, Taiki Kuzu, Keisuke Tachibana, Ryuichi Hirayama, Yoshiaki Okada, Masuo Kondoh
Summary: The blood-brain barrier poses a challenge to drug delivery to the central nervous system. Among the components of the tight junctions in the blood-brain barrier, claudin-5 has been studied extensively as a target for enhancing drug permeation into the brain. However, sustained knockdown of claudin-5 is lethal in mice and administration of an anti-claudin-5 antibody can cause convulsions in nonhuman primates.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
(2022)
Article
Virology
Naiqing Xu, Xinen Tang, Xin Wang, Miao Cai, Xiaowen Liu, Xiaolong Lu, Shunlin Hu, Min Gu, Jiao Hu, Ruyi Gao, Kaituo Liu, Yu Chen, Xiufan Liu, Xiaoquan Wang
Summary: This study found that the H9N2 subtype avian influenza virus has a high airborne transmissibility, while the H7N9 virus does not. The Hemagglutinin protein of the H9N2 virus was found to play a key role in replication, stability, and airborne transmission.
Article
Virology
Samar S. Ewies, Sabry M. Tamam, Ahmed S. Abdel-Moneim, Sherin R. Rouby
Summary: Contagious ecthyma (CE) is a highly contagious viral disease of sheep and goats worldwide. The study provided a clinical description of CE and screened for genetic variation in the B2L gene. Infected sheep exhibited anorexia and oral lesions, while inoculated chicken embryos showed pock lesions. The B2L gene was successfully amplified and found to be highly conserved.
Article
Virology
Yigal Farnoushi, Dan Heller, Avishai Lublin
Summary: In recent years, new variants of avian reovirus (ARV) have caused a variety of symptoms in chickens worldwide, including viral arthritis/tenosynovitis. This study analyzed emerging ARV variants in Israel and found significant genetic diversity. Most ARV isolates in Israel belonged to genotypic cluster 5 (GC5). The study suggests that Israel has not experienced the emergence of new ARV variants since the introduction of the live vaccine (ISR-7585), but ongoing monitoring is needed due to the continuous emergence of ARV variants.
Article
Virology
Shigeru Tajima, Michiyo Kataoka, Yuki Takamatsu, Hideki Ebihara, Chang-Kweng Lim
Summary: Yokose virus (YOKV), a bat-associated flavivirus, was found to replicate at a slower rate in mosquito cells compared to other mosquito-borne flaviviruses. Specific nucleotide mutations in the virus were identified to enhance its proliferation ability in mosquito cells.
Article
Virology
Alejandra Borjabad, Baojun Dong, Wei Chao, David J. Volsky, Mary Jane Potash
Summary: This study investigated HIV brain disease using a mouse model, and found that poly I:C can reverse associated cognitive impairment and reduce virus burden. The results also revealed transcriptional changes related to neuronal function and innate immune responses.
Article
Virology
Ching-Hung Lin, Feng-Cheng Hsieh, Meilin Wang, Chieh Hsu, Hsuan-Wei Hsu, Chun-Chun Yang, Cheng-Yao Yang, Hung-Yi Wu
Summary: This study demonstrates that the synthesis of coronavirus subgenomic mRNA is not solely determined by the sequence homology between the leader TRS and TRS-B, but also by the disassociation of the coronavirus polymerase from the viral genome. This finding provides a new insight into the transcription mechanism of coronaviruses.
Article
Virology
Nicholas S. Kron, Benjamin W. Neuman, Sathish Kumar, Patricia L. Blackwelder, Dayana Vidal, Delphina Z. Walker-Phelan, Patrick D. I. Gibbs, Lynne A. Fieber, Michael C. Schmale
Summary: Two recent studies documented the genome of a novel virus in marine animals, finding that the virus is widespread in apparently healthy animals but not highly expressed in neurons. The studies also identified viral replication factories and high levels of defective genomes in chronically infected animals.
Article
Virology
Andrew M. Ramey, Laura C. Scott, Christina A. Ahlstrom, Evan J. Buck, Alison R. Williams, Mia Kim Torchetti, David E. Stallknecht, Rebecca L. Poulson
Summary: We successfully detected and characterized highly pathogenic avian influenza viruses in hunter-harvested wild waterfowl samples from western Alaska. Genomic analysis revealed three independent viral introductions into Alaska. Our findings demonstrate the utility and potential limitations of using molecular processing approaches directly on original swab samples for viral research and monitoring.
Article
Virology
Ting Gong, Dongdong Wu, Yongzhi Feng, Xing Liu, Qi Gao, Xiaoyu Zheng, Zebu Song, Heng Wang, Guihong Zhang, Lang Gong
Summary: This study discovered that quercetin can inhibit PEDV replication both in vivo and in vitro, and alleviate the clinical symptoms and intestinal injury caused by the virus. This provides a new direction for the development of PED antiviral drugs.
Article
Virology
Min Zhu, Hao Zeng, Jianqiao He, Yaohui Zhu, Pingping Wang, Jianing Guo, Jinfan Guo, Huabo Zhou, Yifeng Qin, Kang Ouyang, Zuzhang Wei, Weijian Huang, Ying Chen
Summary: The reassortment between avian H9N2 and Eurasian avian-like (EA) H1N1 viruses may have potentially changed from avian-to-mammals adaptation. This study found that the introduction of EA H1N1 internal genes into H9N2 virus restored the replication capability and resulted in extreme virulence in some cases. This raises new concerns for public health due to the possible coexistence of H9N2 and EA H1N1 viruses in dogs.