Acts as a growth inhibitor. Can activate p53/TP53, causes G1 arrest and collaborates with CDKN2A to restrict proliferation, but does not require either protein to inhibit DNA synthesis. Redistributes CDKN2A into the nucleoplasm. Involved in maintaining chromosomal stability. . This is the function of TBRG1 (transforming growth factor beta regulator 1, Ensembl gene identifier ENSG00000154144).