| Type: | Domain | Name: | Transcription factor, SBP-box |
| Description: | SBP (for SQUAMOSA-pROMOTER BINDING PROTEIN) domain is a sequence specific DNA-binding domain found in plant proteins []. Members of family probably function as transcription factors involved in the control of early flower development []. They share a highly conserved DNA-binding domain that contains two zinc-binding sites. Among the 11 possible ligands for the zinc atoms that are conserved in the SBP zinc finger, only 8 are used. The SBP zinc finger follows the general pattern C-x4-C-x16-C-x2-[HC]-x15-C-x2-C-x3-H-x11-C. Three other histidines are well conserved but not involved in zinc binding [, ].In vitro experiments show that the SBP zinc finger preferentially binds the consensus sequence -TNCGTACAA- []. However, little is known of the physiological functions of these putative transcriptional regulators beyond their ability to bind DNA.The solution structure of the SBP zinc finger has been solved []. The first four Cys or His coordinate one zinc ion and the last four coordinate the other. It can be viewed as two structural subdomains, each subdomain containing a single zinc-binding pocket. The N-terminal subdomain consists of two short alpha helices whereas the C-terminal one contains a three-stranded antiparallel beta-sheet. | Short Name: | Transcpt_factor_SBP-box |
