Low-density lipoprotein receptor class A domain-containing protein 4 (LDLRAD4)

Low-density lipoprotein receptor class A domain-containing protein 4 (LDLRAD4) is a transmembrane protein characterized by the presence of an LDL-receptor class A domain and functional PPxY motifs[6]. It acts as a negative regulator of TGF-beta signaling by binding to R-SMAD proteins (SMAD2/3), thereby affecting cellular processes such as proliferation, differentiation, apoptosis, and motility[1][5][6]. In hepatic cancer and other tumor tissues, LDLRAD4 is upregulated, promotes cell growth and migration, and facilitates lysosomal trafficking via interaction with the ubiquitin ligase Nedd4[3][5]. Genetic studies associate LDLRAD4 with oncogenic activity, prognostic relevance in gastrointestinal stromal tumors, and possible roles in vascular and inflammatory diseases[5]. Mechanistically, it acts primarily as a signal transduction inhibitor through TGF-beta pathway modulation. Its established and putative clinical significance positions LDLRAD4 as both a potential therapeutic target and a disease biomarker in oncology and vascular pathologies[1][3][5][6].

Other names

C18orf1clone 22LRAD4low density lipoprotein receptor class A domain containing 4Low-density lipoprotein receptor class A domain-containing protein 4

Negative regulation of TGF-beta signaling via R-SMAD binding, competing with other adaptors for SMAD2/3 binding[1][3][5][6]