InterPro domain: IPR032698

This domain can be found in the N terminus of the bacterial SirB1 protein. It can also be found in the mammalian F-box only protein 21 (FBXO21).

SirB is required for maximal expression of sirC, which encodes an SPI1-encoded transcription factor [ 1 ].

FBXO21 is a substrate-recognition component of the SCF (SKP1-CUL1-F-box protein)-type E3 ubiquitin ligase complex [ 2 ].

1. A HilA-independent pathway to Salmonella typhimurium invasion gene transcription. J. Bacteriol. 181, 3096-104
2. FBXO21 mediates the ubiquitylation and proteasomal degradation of EID1. Genes Cells 20, 667-74