Roles and Regulatory Mechanisms of Ectodomain Shedding Elucidated by Proteomic Analysis: Shedding Susceptibility of Membrane Proteins Is Determined through Their Biosynthesis Pathways

Ectodomain shedding is a post-translational modification mechanism by which the entire extracellular domain of membrane proteins is liberated through juxtamembrane processing. Because shedding rapidly and irreversibly alters the characteristics of cells, this process is properly regulated. However, the molecular mechanisms governing the propensity of membrane proteins to shedding are largely unknown. Here, we present evidence that negatively charged amino acids within the stalk region, an unstructured juxtamembrane region at which shedding occurs, contribute to shedding susceptibility. We show that two activated leukocyte cell adhesion molecule (ALCAM) protein variants produced by alternative splicing have different susceptibilities to ADAM metallopeptidase domain 17 (ADAM17)-mediated shedding. Of note, the inclusion of a stalk region encoded by a 39-bp-long alternative exon conferred shedding resistance. We found that this alternative exon encodes a large proportion of negatively charged amino acids, which we demonstrate are indispensable for conferring the shedding resistance. We also show that the introduction of negatively charged amino acids into the stalk region of shedding-susceptible ALCAM variant protein attenuates its shedding. Furthermore, we observed that negatively charged amino acids residing in the stalk region of Erb-B2 receptor tyrosine kinase 4 (ERBB4) are indispensable for its shedding resistance. Collectively, our results indicate that negatively charged amino acids within the stalk region interfere with the shedding of multiple membrane proteins. We conclude that the composition of the stalk region determines the shedding susceptibility of membrane proteins.

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Molecular regulatory mechanisms of Escherichia coli O157:H7 in response to ultrasonic stress revealed by proteomic analysis

Ultrasonics Sonochemistry ◽

10.1016/j.ultsonch.2019.104835 ◽

2020 ◽

Vol 61 ◽

pp. 104835 ◽

Cited By ~ 3

Author(s):

Jiao Li ◽

Xinglin Zhang ◽

Muthupandian Ashokkumar ◽

Donghong Liu ◽

Tian Ding

Keyword(s):

Escherichia Coli ◽

Proteomic Analysis ◽

Regulatory Mechanisms ◽

Escherichia Coli O157 ◽

Molecular Regulatory Mechanisms

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Proteomic Analysis of Plasma Membrane Proteins in an In Vitro Blood-Brain Barrier Model

Proteomics - Human Diseases and Protein Functions ◽

10.5772/30543 ◽

2012 ◽

Cited By ~ 1

Author(s):

Sophie Duban-Deweer ◽

Johan Hachani ◽

Barbara Deracinois ◽

Romo Cecchelli ◽

Christophe Flahaut ◽

...

Keyword(s):

Plasma Membrane ◽

Membrane Proteins ◽

Blood Brain Barrier ◽

Proteomic Analysis ◽

Brain Barrier ◽

Plasma Membrane Proteins ◽

Blood Brain ◽

Blood Brain Barrier Model ◽

Barrier Model

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Quantitative proteomics identifies a plasma multi-protein model for detection of hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-020-72510-9 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Zhenhua Du ◽

Xinyi Liu ◽

Xiaojun Wei ◽

Hongbo Luo ◽

Peiyao Li ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Membrane Proteins ◽

Early Detection ◽

Proteomic Analysis ◽

Quantitative Proteomics ◽

Serum Biomarkers ◽

Diagnostic Efficacy ◽

Protein Model ◽

Tumor Tissues ◽

Normal Controls

Abstract More efficient biomarkers are needed to facilitate the early detection of hepatocellular carcinoma (HCC). We aimed to identify candidate biomarkers for HCC detection by proteomic analysis. First, we performed a global proteomic analysis of 10 paired HCC and non-tumor tissues. Then, we validated the top-ranked proteins by targeted proteomic analyses in another tissue cohort. At last, we used enzyme-linked immunosorbent assays to validate the candidate biomarkers in multiple serum cohorts including HCC cases (HCCs), cirrhosis cases (LCs), and normal controls (NCs). We identified and validated 33 up-regulated proteins in HCC tissues. Among them, eight secretory or membrane proteins were further evaluated in serum, revealing that aldo–keto reductase family 1 member B10 (AKR1B10) and cathepsin A (CTSA) can distinguish HCCs from LCs and NCs. The area under the curves (AUCs) were 0.891 and 0.894 for AKR1B10 and CTSA, respectively, greater than that of alpha-fetoprotein (AFP; 0.831). Notably, combining the three proteins reached an AUC of 0.969, which outperformed AFP alone (P < 0.05). Furthermore, the serum AKR1B10 levels dramatically decreased after surgery. AKR1B10 and CTSA are potential serum biomarkers for HCC detection. The combination of AKR1B10, CTSA, and AFP may improve the HCC diagnostic efficacy.

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