Rap1gap, short for Rap1 GTPase-activating protein, is an important tumor suppressor. It is involved in regulating the GTP-GDP form switch of Rap1, a monomeric GTPase of the Ras family. Rap1gap is associated with multiple signaling pathways such as the AMPK/SIRT1/NF-κB and AMPK/AKT/mTOR pathways, playing a role in various biological processes like cell-matrix adhesion, autophagy, and oxidative stress regulation [1,2,6]. Genetic models, especially knockout (KO) and conditional knockout (CKO) mouse models, have been crucial in studying its functions.

In cardiac-specific Rap1GAP-CKO mice, after myocardial infarction (MI), the hearts showed alleviated apoptosis, inflammation, infarct size, and left ventricular dysfunction compared to control mice. Rap1GAP was found to inhibit the AMPK/SIRT1 pathway and activate the NF-κB signaling pathway, exacerbating the damage to myocardial cells caused by ischemia and hypoxia [1]. In another study, in rats infused with Ang II, overexpression of Rap1GAP in cardiomyocytes exacerbated Ang II-induced cardiomyocyte hypertrophy, ROS generation, and cell apoptosis, while inhibiting autophagy. Knockdown of Rap1GAP by siRNA attenuated these effects and activated the AMPK/AKT/mTOR signaling pathway [2].

In conclusion, Rap1gap is a significant gene involved in multiple biological functions and disease-related processes. Studies using KO/CKO mouse models have revealed its role in myocardial infarction and cardiomyocyte hypertrophy, highlighting its potential as a therapeutic target in these cardiac-related disease areas. Additionally, it may also play a role in endometriosis, endometrial cancer, leukemia, and thyroid cancer, as changes in its expression have been associated with these diseases [3,4,7,5,8,9].