Interferon Related Developmental Regulator 2 (IFRD2)

SKMc15 was homozygously deleted in 3 of 63 SCLC cell lines. Northern blot analysis showed that SKMc15 was expressed as a 1.8- to 2.0-kb mRNA in all analyzed fetal and adult tissues and in most lung tumor cell lines. the sequence of the 442-amino acid SKMc15 protein is 83% similar to a partial sequence of the putative mouse interferon beta-2 protein. The SKMc15 protein also shows 75% similarity to the rat early response gene PC4 and its murine homolog, TIS7.

IFRD2 is a soluble nuclear protein that is 93% identical to the mouse protein. It contains a predicted bipartite nuclear localization signal and an armadillo-beta catenin (CTNNB1)-like repeat. No mutations were detected in any lung cancer cell lines tested.