LAMTOR5 functions as a critical component of the Ragulator complex, mediating amino acid sensing and mTORC1 activation at the lysosomal surface 1. The protein physically associates with ATP6V1A, an essential v-ATPase subunit, promoting V0/V1 holoenzyme assembly to facilitate lysosomal acidification 1. This interaction affects lysosomal tethering of Rag GTPases and modulates their interaction with mTORC1 for activation 1. LAMTOR5 demonstrates significant disease relevance, with decreased expression in systemic lupus erythematosus patients' PBMCs, while myeloid-specific ablation in mice produces SLE-like manifestations 1. In cancer contexts, LAMTOR5 exhibits oncogenic properties through multiple mechanisms: it disrupts LC3-p62-mediated autophagy and prevents p62 proteasomal degradation in hepatocellular carcinoma 2, and promotes CHOP silencing via DNA hypermethylation and miRNA regulation 3. LAMTOR5 expression is significantly elevated in colorectal cancer tissues and serves as a diagnostic biomarker 4. Additionally, LAMTOR5 supports IL-7-mediated T cell expansion through integrated glucose and amino acid sensing 5. Clinically, lenvatinib can target the LAMTOR5 pathway, providing therapeutic potential for liver cancer treatment 23.