The inhibitory SAPS3 – AMPK interaction detected in HEK293 cells is not detectable in muscle or liver from humans or mice

It has been proposed that the regulatory Sit4-associated protein subunit 3 (SAPS3) of protein phosphatase 6 (PP6C) acts as an AMP-activated protein kinase (AMPK) inhibitor by recruiting PP6C to dephosphorylate AMPKα-T172. While we confirm this interaction in HEK293 cells, we find limited evidence for a SAPS3–AMPK interaction in metabolically perturbed liver and skeletal muscle from humans and mice. Across fasting, high-fat diet feeding, and exercise conditions, co-immunoprecipitation assays failed to detect endogenous SAPS3–AMPK and PP6C–AMPK interactions. These findings challenge the physiological relevance of SAPS3/PP6C as regulators of AMPK in mature tissues and highlight the need for further investigation into the regulation of AMPK by protein phosphatases in vivo.
, , # The inhibitory SAPS3–AMPK interaction detected in HEK293 cells is not detectable in muscle or liver from humans or mice

Dataset DOI: [10.5061/dryad.w6m905r1k](10.5061/dryad.w6m905r1k)

## Description of the data and file structure

This dataset contains the summarized experimental data supporting figures in a study examining the metabolic effects of SAPS3 and AMPK signaling in mice subjected to either fasting or high-fat diet (HFD). The data are organized according to figure panels from the manuscript and include key physiological, biochemical, and molecular readouts relevant to energy metabolism and insulin sensitivity. Experimental groups typically include fasted/fed and chow/HFD-fed animals.

### Files and variables

#### File: Data_summary_SAPS3-AMPK_v2.xlsx

**Description:** This summary Excel file is intended for transparency and reproducibility and may serve as a reference for reviewers and collaborators in interpreting the figures and statistical analyses presented in the ma...,