Spi 1 (PU.1) 5' UTR regulatory element

The Spi-1 (PU.1) 5' UTR regulatory element is an RNA element found in the 5' UTR of Spi-1 mRNA which is able to inhibit the translation Spi-1 transcripts by 8-fold. Spi-1 regulates myeloid gene expression during haemopoietic development. Mutations in this regulatory region of the 5' UTR can lead to overexpression of Spi-1 which has been linked to development of leukaemia.