MALAT1-associated small cytoplasmic RNA (mascRNA)

MASCRNA (mascRNA, MALAT1-associated small cytoplasmic RNA) is a small tRNA-like noncoding RNA produced from the 3′ end of the MALAT1 transcript after cleavage by tRNA-processing enzymes RNase P and RNase Z[1][6]. It is localized primarily to the cytoplasm and is not thought to be transcribed as an independent gene[6][5]. mascRNA acts by binding and positively regulating glutaminyl-tRNA synthetase (QARS) on the post-transcriptional level, thereby promoting global protein translation and enhancing cell proliferation[1]. Its expression also impacts immune functions, serving as a feedback regulator to suppress TLR-induced proinflammatory cytokine production in macrophages by inhibiting MyD88/TAK1-dependent NF-κB and MAPK signaling, and promoting proteasomal degradation of TRAF6[3]. While mascRNA plays roles in cellular regulation and disease contexts such as cancer and inflammation, it is not considered a conventional therapeutic drug target nor used as a biomarker. Its molecular mechanism is distinct from typical enzymes or receptors, underlying the tRNA-like regulatory paradigm in mammalian cells[1][3][6][5].

Other names

mascRNAMALAT1-associated small cytoplasmic RNA