The Drosophila septate junctions beyond barrier function: Review of the literature, prediction of human orthologs of the SJ‐related proteins and identification of protein domain families

Abstract The Patched-related superfamily of transmembrane proteins can transport lipids or other hydrophobic molecules across cell membranes. While the Hedgehog receptor Patched has been intensively studied, much less is known about the biological roles of other Patched-related family members. Caenorhabditis elegans has a large number of Patched-related proteins, despite lacking a canonical Hedgehog pathway. Here, we show that PTR-4 promotes the assembly of the precuticle apical extracellular matrix, a transient and molecularly distinct matrix that precedes and patterns the later collagenous cuticle or exoskeleton. ptr-4 mutants share many phenotypes with precuticle mutants, including defects in eggshell dissolution, tube shaping, alae (cuticle ridge) structure, molting, and cuticle barrier function. PTR-4 localizes to the apical side of a subset of outward-facing epithelia, in a cyclical manner that peaks when precuticle matrix is present. Finally, PTR-4 is required to limit the accumulation of the lipocalin LPR-3 and to properly localize the Zona Pellucida domain protein LET-653 within the precuticle. We propose that PTR-4 transports lipids or other hydrophobic components that help to organize the precuticle and that the cuticle and molting defects seen in ptr-4 mutants result at least in part from earlier disorganization of the precuticle.

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Up-regulation of tight junction-related proteins and increase of human epidermal keratinocytes barrier function by Saccharomycosis ferment filtrate

Journal of Cosmetics Dermatological Sciences and Applications ◽

10.4236/jcdsa.2011.11003 ◽

2011 ◽

Vol 01 (01) ◽

pp. 15-24

Author(s):

Jong-Hwei Pang ◽

Wen-Rou Wong ◽

Tomohiro Hakozaki ◽

Takashi Yoshii ◽

Tzu-Ya Chen

Keyword(s):

Tight Junction ◽

Barrier Function ◽

Epidermal Keratinocytes ◽

Human Epidermal Keratinocytes ◽

Related Proteins

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PSX-A-9 Late-Breaking: Effects of farm noise on ileum intestinal barrier function of pullets

Journal of Animal Science ◽

10.1093/jas/skab235.673 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 367-367

Author(s):

Chun Li ◽

Runxiang Zhang ◽

Hanlin Yu ◽

Yanru Feng ◽

Jianhong Li ◽

...

Keyword(s):

Barrier Function ◽

Intestinal Barrier ◽

Animal Husbandry ◽

Low Noise ◽

Intestinal Barrier Function ◽

Control Group ◽

Tissue Samples ◽

Real Time Quantitative Pcr ◽

Junction Protein ◽

Related Proteins

Abstract Noise is a potential but not negligible environmental factor in animal husbandry. To investigate the effects of farm noise on intestinal barrier function of pullets, 336 Hailanhe pullets aged 1 day were randomly divided into 3 groups: control group (CON), low noise group (LN), high noise group (HN). LN group and HN group were exposed to noise respectively at 65–75 dB and 85–95 dB, the average and the range of the highest loudness of noise in laying hens’ farms for 6h every day (7:00-19:00, hourly intervals for one hour) and lasted 4 weeks. Non additional noise addition in CON group, noise loudness of which was less than 40dB. 6 birds were randomly chosen form each group after every week of noise stimulation for ileum tissue samples. Hematoxylin-eosin stain (HE stain), immunofluorescence, and real-time quantitative PCR (qRT-PCR) were used to determine changes in ileum structure, expression of intestinal barrier related proteins and mRNAs and HSPs. Results shown that 1 week and 2 weeks after noise exposed inflammatory cell infiltration reduced, the expression of intestinal barrier related proteins (Occludin, Mucin2 and ZO-1) and mRNAs (Claudin-1, Claudin-4, E-cadherin, Occludin, Mucin2, ZO-1 and ZO-2) were significantly increased (P < 0.05), the mRNA expression of HSPs decreased (P < 0.05) or have no significate changes (P > 0.05). After 4 weeks of noise treatment, the expression of mRNAs of intestinal tight junction protein and mucin, HSPs were significantly decreased (P < 0.05). There was no difference between the LN and HN groups on those indicators (P > 0.05). The study indicates that noise at 65-75dB and 85-95dB does not cause stress to ileum of pullets while promote the development of intestinal barrier of chicks within 2 weeks maybe by mild stimulation and birds restored to balance due to habitualization after 4 weeks of noise treatment.

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Filaggrin and tight junction proteins are crucial for IL-13-mediated esophageal barrier dysfunction

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00404.2017 ◽

2018 ◽

Vol 315 (3) ◽

pp. G341-G350 ◽

Cited By ~ 11

Author(s):

Liping Wu ◽

Tadayuki Oshima ◽

Min Li ◽

Toshihiko Tomita ◽

Hirokazu Fukui ◽

...

Keyword(s):

Epithelial Cells ◽

Tight Junction ◽

Barrier Function ◽

Epithelial Barrier ◽

Tight Junction Proteins ◽

Barrier Dysfunction ◽

Esophageal Epithelial Cells ◽

Air Liquid Interface ◽

Related Proteins ◽

Junction Proteins

Eosinophilic esophagitis (EoE) is an allergy-mediated disease that is accompanied by IL-13 overexpression and an impaired esophageal barrier. Filaggrin (FLG) and tight junction (TJ) proteins are considered to contribute to epithelial barrier function. However, their functional involvement in EoE has not been elucidated. Here, we aimed to determine the IL-13-mediated barrier dysfunction and expression of TJ-related proteins in EoE and to characterize interactions among TJ-related proteins involved in the barrier function of the esophageal epithelium. Biopsy specimens from EoE patients were analyzed. Primary human esophageal epithelial cells (HEECs) were cultured using an air-liquid interface (ALI) system. The permeability of TJs was assayed by biotinylation. Transepithelial electrical resistance (TEER) was measured after stimulation with IL-13 and after siRNA silencing of FLG expression. FLG and TJ genes and proteins were assessed by quantitative RT-PCR, Western blot analysis, and immunofluorescent staining. The biotinylation reagent diffused through the paracellular spaces of whole stratified epithelial layers in EoE biopsy samples. The TEER decreased in ALI-cultured HEECs after IL-13 stimulation. Although the protein level of FLG decreased, that of the TJ proteins increased in the mucosa of EoE biopsy samples and in ALI-cultured HEECs after IL-13 stimulation. IL-13 altered the staining patterns of TJ proteins and the epithelial morphology. FLG siRNA transfection significantly decreased TEER. The IL-13-mediated reduced esophageal barrier is associated with the altered expression pattern but not with the levels of TJ-associated proteins. A deficiency of FLG altered the stratified epithelial barrier. NEW & NOTEWORTHY Esophageal permeability to small molecules was increased in patients with eosinophilic esophagitis (EoE) and could be induced by IL-13 in our unique air-liquid interface-cultured primary multilayer human esophageal epithelial cells in vitro. A deficiency of filaggrin disrupted the esophageal stratified epithelial barrier. The decreased esophageal barrier in EoE was associated with the altered staining pattern of tight junction proteins, although the levels of the proteins themselves do not appear to be changed.

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