Abstract
Mammalian mitochondrial ribosomal proteins are a group of protein factors encoded by nuclear genes, responsible for the synthesis of proteins in mitochondria. As a member of mitochondrial ribosomal proteins, MRPL42 (mitochondrial ribosomal protein L42) belongs to 28S and 39S subunits. The current literature showed that its role in lung adenocarcinoma (LUAD) was not clear. We found that MRPL42 was highly expressed in early-stage LUAD tissues and cell lines, and remarkably related to the prognosis of patients. Knockdown of MRPL42 could reduce the proliferation and colonization, promote cell cycle arrest in G1/S phase, and weaken the migration and invasion ability of LUAD cells in vitro. Moreover, depletion of MRPL42 also inhibited tumor growth in vivo. Bioinformatics analysis found that YY1 may bind to the promoter region upstream of the MRPL42 gene to promote the transcription of MRPL42, which was verified by the ChIP and Dual luciferase reporter assay. QRT-PCR confirmed that knocking down YY1 could attenuate the expression of MRPL42. In summary, MRPL42 acts as an oncogene in LUAD, and its expression level is regulated by YY1.