A dengue type 2 reporter virus assay amenable to high-throughput screening

BACKGROUND: A higher rate of attenuation of molecules in drug discovery has enabled pharmaceutical companies to enhance the efficiency of their hit identification and lead optimization. Selection and development of appropriate in-vitro and in-vivo strategies may improve this process as primary and secondary screening utilize both strategies. In-vivo approaches are too relentless and expensive for assessing hits. Therefore, it has become indispensable to develop and implement suitable in-vitro screening methods to execute the required activities and meet the respective targets. However, the selection of an appropriate in-vitro assay for specific evaluation of cellular activity is no trivial task. It requires thorough investigation of the various parameters involved. AIM: In this review, we aim to discuss in-vitro assays for type 2 diabetes (T2D), which have been utilized extensively by researchers over the last five years, including target-based, non-target based, low-throughput, and high-throughput screening assays. METHODS: The literature search was conducted using databases including Scifinder, PubMed, ScienceDirect, and Google Scholar to find the significant published articles. DISCUSSION and CONCLUSION: The accuracy and relevance of in-vitro assays have a significant impact on the drug discovery process for T2D, especially in assessing the antidiabetic activity of compounds and identifying the site of effect in high-throughput screening. The report reviews the advantages, limitations, quality parameters, and applications of the probed invitro assays, and compares them with one another to enable the selection of the optimal method for any purpose. The information on these assays will accelerate numerous procedures in the drug development process with consistent quality and accuracy.

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Quantitative, High-Throughput Assays for Proteolytic Degradation of Amylin

Methods and Protocols ◽

10.3390/mps3040081 ◽

2020 ◽

Vol 3 (4) ◽

pp. 81

Author(s):

Caitlin N. Suire ◽

Monica K. Brizuela ◽

Malcolm A. Leissring

Keyword(s):

High Throughput ◽

High Throughput Screening ◽

Peptide Hormone ◽

Proteolytic Degradation ◽

Insulin Degrading Enzyme ◽

Islet Amyloid ◽

Health And Disease ◽

Pancreatic Peptide

Amylin is a pancreatic peptide hormone that regulates glucose homeostasis but also aggregates to form islet amyloid in type-2 diabetes. Given its role in both health and disease, there is renewed interest in proteolytic degradation of amylin by insulin-degrading enzyme (IDE) and other proteases. Here, we describe the development and detailed characterization of three novel assays for amylin degradation, two based on a fluoresceinated and biotinylated form of rodent amylin (fluorescein-rodent amylin-biotin, FrAB), which can be used for any amylin protease, and another based on an internally quenched fluorogenic substrate (FRET-based amylin, FRAM), which is more specific for IDE. The FrAB-based substrate can be used in a readily implemented fluorescence-based protocol or in a fluorescence polarization (FP)-based protocol that is more amenable to high-throughput screening (HTS), whereas the FRAM substrate has the advantage of permitting continuous monitoring of proteolytic activity. All three assays yield highly quantitative data and are resistant to DMSO, and the FRAM and FP-based FrAB assay are ideally suited to HTS applications.

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Genetically encoded multimode reporter of adaptor protein 3 (AP-3) traffic in budding yeast

10.1101/314286 ◽

2018 ◽

Author(s):

Rachael L. Plemel ◽

Greg Odorizzi ◽

Alexey J. Merz

Keyword(s):

High Throughput ◽

High Throughput Screening ◽

Budding Yeast ◽

Agar Plate ◽

Adaptor Protein ◽

Epileptic Encephalopathy ◽

Early Endosomes ◽

Hermansky Pudlak Syndrome ◽

Functional Deficiency

SYNOPSISThe AP-3 (adaptor complex 3) mediates traffic from the late Golgi or early endosomes to late endosomal compartments. Here, a synthetic reporter is presented that allows convenient monitoring of AP-3 traffic, and direct screening or selection for mutants with defects in the pathway. The reporter can be assayed by fluorescence microscopy or in liquid or agar plate formats and is adaptable to high-throughput screening.SUMMARYAP-3 (adaptor complex 3) mediates traffic from the late Golgi or early endosomes to late endosomal compartments. In mammals, mutations in AP-3 cause Hermansky-Pudlak Syndrome type 2, cyclic neutropenias, and a form of epileptic encephalopathy. In budding yeast, AP-3 carries cargo directly from the trans-Golgi to the lysosomal vacuole. Despite the pathway’s importance and its discovery two decades ago, rapid screens and selections for AP-3 mutants have not been available. We now report GNSI, a synthetic, genetically encoded reporter that allows rapid plate-based assessment of AP-3 functional deficiency, using either chromogenic or growth phenotype readouts. This system identifies defects in both the formation and consumption of AP-3 carrier vesicles and is adaptable to high-throughput screening or selection in both plate array and liquid batch culture formats. Episomal and integrating plasmids encoding GNSI have been submitted to the Addgene repository.

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