Screening and identification of cAMP-binding proteins in alveolar macrophages during the pathological process of silicosis

doi:10.16352/j.issn.1001-6325.2026.08.1042

Abstract

Abstract: Objective To investigate the regulatory mechanisms of the cyclic adenosine monophosphate (cAMP) signaling pathway in the pathogenesis of silicosis by screening and identifying novel proteins that interact with cAMP in mouse alveolar macrophage cells (MH-S) stimulated with silica. Methods MH-S cells were divided into a control group and an experimental group. Intracellular cAMP levels were measured using enzyme-linked immunosorbent assay (ELISA). Pull-down assays were performed with cAMP-conjugated agarose beads to capture cAMP-binding proteins. These proteins were separated by SDS-PAGE and visualized by silver staining. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics was used to screen for potential cAMP-binding proteins. AlphaFold was used to predict the structures and assess the binding capacities of selected candidate proteins. Results Compared with the control group, the intracellular cAMP level in the experimental group was significantly decreased (P＜0.01) and the profile of cAMP-binding proteins was altered. A total of 5 upregulated and 413 down- regulated proteins were identified. AlphaFold predictions indicated that the upregulated proteins might be potential cAMP-binding proteins with high confidence. Conclusions Silica stimulation can alter the intracellular cAMP levels and profile of cAMP-binding proteins in alveolar macrophages. These novel cAMP-binding proteins may participate in the occurrence and progression of silicosis by increasing expression levels or enhancing binding affinity to cAMP, providing a new avenue for the discovery of potential therapeutic targets for silicosis.

Key words: silicosis, alveolar macrophage, cAMP-binding proteins, proteomics

CLC Number:

R363.2

ZHOU Huan, WANG Yiyang, ZHANG Tiantian, WANG Jing. Screening and identification of cAMP-binding proteins in alveolar macrophages during the pathological process of silicosis[J]. Basic & Clinical Medicine, 2026, 46(8): 1042-1050.

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