Dual regulator of transcription and autophagy. Positively regulates autophagy and is required for autophagosome formation and processing. May act as a scaffold protein that recruits MAP1LC3A, GABARAP and GABARAPL2 and brings them to the autophagosome membrane by interacting with VMP1 where, in cooperation with the BECN1-PI3-kinase class III complex, they trigger autophagosome development. Acts as a transcriptional activator of THRA. {ECO:0000269|PubMed:18030323, ECO:0000269|PubMed:19056683, ECO:0000269|PubMed:22470510}. This is the function of TP53INP2 (tumor protein p53 inducible nuclear protein 2, ENSG00000078804).