precise-visualization-insulin-receptors-b-murine-brain-with-an-rna

Precise Visualization of Insulin Receptors A and B in Murine Brain with an RNA <em>In Situ</em> Hybridization Assay

Insulin receptors (IRs) are widely expressed across all tissues and all cell types. It exists in two functionally distinct isoforms -- IR-A and IR-B -- ...

National Institutes of Health

Autosomal recessive polycystic kidney disease (OMIM 263200) is a serious condition of the kidney and liver caused by mutations in a single gene, PKHD1. This gene encodes fibrocystin/polyductin (FPC, PD1), a large protein shown by in vitro studies to undergo Notch-like processing. Its cytoplasmic tail, reported to include a ciliary targeting sequence, a nuclear localization signal, and a polycystin-2 binding domain, is thought to traffic to the nucleus after cleavage. We now report a novel mouse line with a triple HA-epitope "knocked-in" to the C-terminus along with lox P sites flanking exon 67, which encodes most of the C-terminus (Pkhd1). The triple HA-epitope has no functional effect as assayed by phenotype and allows in vivo tracking of Fibrocystin. We used the HA tag to identify previously predicted Fibrocystin cleavage products in tissue. In addition, we found that Polycystin-2 fails to co-precipitate with Fibrocystin in kidney samples. Immunofluorescence studies with anti-HA antibodies demonstrate that Fibrocystin is primarily present in a sub-apical location the in kidney, biliary duct, and pancreatic ducts, partially overlapping with the Golgi. In contrast to previous studies, the endogenous protein in the primary cilia was not detectable in mouse tissues. After Cre-mediated deletion, homozygous Pkhd1 mice are completely normal. Thus, Pkhd1 is a valid model to track Pkhd1-derived products containing the C-terminus. Significantly, exon 67 containing the nuclear localization signal and the polycystin-2 binding domain is not essential for Fibrocystin function in our model.

A novel model of autosomal recessive polycystic kidney questions the role of the fibrocystin C-terminus in disease mechanism.

Critical care ultrasound (CCUS) has been used by many Intensive Care Units(ICUs) worldwide, so as to guiding the diagnosis and the treatment. However, none of the publications currently systematically describe the utilization of CCUS to analyze the characteristics of hemodynamics and lung pathology upon the new admission to ICU and its potential role in patients' prognosis prediction. In this retrospective clinical study, we have demonstrated and analyzed the characteristics of hemodynamics and lung pathology assessed by CCUS and investigated its potential to predict patient outcome.

The utilization of critical care ultrasound to assess hemodynamics and lung pathology on ICU admission and the potential for predicting outcome.

Major advances have been made to improve the sensitivity of mass analyzers, spectral quality, and speed of data processing enabling more comprehensive proteome discovery and quantitation. While focus has recently begun shifting toward robust proteomics sample preparation efforts, a high-throughput proteomics sample preparation is still lacking. We report the development of a highly automated universal 384-well plate sample preparation platform with high reproducibility and adaptability for extraction of proteins from cells within a culture plate. Digestion efficiency was excellent in comparison to a commercial digest peptide standard with minimal sample loss while improving sample preparation throughput by 20- to 40-fold (the entire process from plated cells to clean peptides is complete in ∼300 min). Analysis of six human cell types, including two primary cell samples, identified and quantified ∼4,000 proteins for each sample in a single high-performance liquid chromatography (HPLC)-tandem mass spectrometry injection with only 100-10K cells, thus demonstrating universality of the platform. The selected protein was further quantified using a developed HPLC-multiple reaction monitoring method for HeLa digests with two heavy labeled internal standard peptides spiked in. Excellent linearity was achieved across different cell numbers indicating a potential for target protein quantitation in clinical research.

A Universal and High-Throughput Proteomics Sample Preparation Platform.

The tongue is a complex multifunctional organ that interacts and senses both interoceptively and exteroceptively. Although it is easily visible to almost all of us, it is relatively understudied and what is in the literature is often contradictory or is not comprehensively reported. The tongue is both a motor and a sensory organ: motor in that it is required for speech and mastication, and sensory in that it receives information to be relayed to the central nervous system pertaining to the safety and quality of the contents of the oral cavity. Additionally, the tongue and its taste apparatus form part of an innate immune surveillance system. For example, loss or alteration in taste perception can be an early indication of infection as became evident during the present global SARS-CoV-2 pandemic. Here, we particularly emphasize the latest updates in the mechanisms of taste perception, taste bud formation and adult taste bud renewal, and the presence and effects of hormones on taste perception, review the understudied lingual immune system with specific reference to SARS-CoV-2, discuss nascent work on tongue microbiome, as well as address the effect of systemic disease on tongue structure and function, especially in relation to taste.

Physiology of the tongue with emphasis on taste transduction.

Fibrocystin/Polyductin (FPC), encoded by PKHD1, is associated with autosomal recessive polycystic kidney disease (ARPKD), yet its precise role in cystogenesis remains unclear. Here we show that FPC undergoes complex proteolytic processing in developing kidneys, generating three soluble C-terminal fragments (ICDs). Notably, ICD, contains a novel mitochondrial targeting sequence at its N-terminus, facilitating its translocation into mitochondria. This enhances mitochondrial respiration in renal epithelial cells, partially restoring impaired mitochondrial function caused by FPC loss. FPC inactivation leads to abnormal ultrastructural morphology of mitochondria in kidney tubules without cyst formation. Moreover, FPC inactivation significantly exacerbates renal cystogenesis and triggers severe pancreatic cystogenesis in a Pkd1 mouse mutant Pkd1 in which cleavage of Pkd1-encoded Polycystin-1 at the GPCR Proteolysis Site is blocked. Deleting ICD enhances renal cystogenesis without inducing pancreatic cysts in Pkd1 mice. These findings reveal a direct link between FPC and a mitochondrial pathway through ICD cleavage, crucial for cystogenesis mechanisms.

Fibrocystin/Polyductin releases a C-terminal fragment that translocates into mitochondria and suppresses cystogenesis.

We sought to determine whether ongoing taste disturbance in the postacute sequelae of coronavirus disease 2019 period is associated with persistent virus in primary taste tissue.

Long-Term Dysfunction of Taste Papillae in SARS-CoV-2.

Type 1 diabetes (T1D) occurs because of islet infiltration by autoreactive immune cells leading to destruction of beta cells and it is becoming evident that beta cell dysfunction partakes in this process. We previously reported that genetic deletion and pharmacological antagonism of the cannabinoid 1 receptor (CB1) in mice improves insulin synthesis and secretion, upregulates glucose sensing machinery, favors beta cell survival by reducing apoptosis, and enhances beta cell proliferation. Moreover, beta cell specific deletion of CB1 protected mice fed a high fat high sugar diet against islet inflammation and beta cell dysfunction. Therefore, we hypothesized that it would mitigate the dysfunction of beta cells in the precipitating events leading to T1D.

Beta cell specific cannabinoid 1 receptor deletion counteracts progression to hyperglycemia in non-obese diabetic mice.

Corrigendum to "Beta cell specific cannabinoid 1 receptor deletion counteracts progression to hyperglycemia in non-obese diabetic mice" [Mol Metab 82 (2024 April) 101906].

Article	Year
A novel model of autosomal recessive polycystic kidney questions the role of the fibrocystin C-terminus in disease mechanism. Kidney international\| PubMed ID: 28729032	2017
The utilization of critical care ultrasound to assess hemodynamics and lung pathology on ICU admission and the potential for predicting outcome. PloS one\| PubMed ID: 28806783	2017
A Universal and High-Throughput Proteomics Sample Preparation Platform. Analytical chemistry\| PubMed ID: 34110797	2021
Physiology of the tongue with emphasis on taste transduction. Physiological reviews\| PubMed ID: 36422992	2023
Fibrocystin/Polyductin releases a C-terminal fragment that translocates into mitochondria and suppresses cystogenesis. Nature communications\| PubMed ID: 37845212	2023
Long-Term Dysfunction of Taste Papillae in SARS-CoV-2. NEJM evidence\| PubMed ID: 38145006	2023
Beta cell specific cannabinoid 1 receptor deletion counteracts progression to hyperglycemia in non-obese diabetic mice. Molecular metabolism\| PubMed ID: 38423253	2024
Corrigendum to "Beta cell specific cannabinoid 1 receptor deletion counteracts progression to hyperglycemia in non-obese diabetic mice" [Mol Metab 82 (2024 April) 101906]. Molecular metabolism\| PubMed ID: 38499184	2024

Qin Yao

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