Protein Family Models

AraC is a bacterial transcriptional regulatory protein with a DNA-binding domain at the C-terminus, HTH_AraC, Pfam:PF00165, and this dimerisation domain which harbours the arabinose-binding pocket at the N-terminus. AraC positively and negatively regulates expression of the proteins required for the uptake and catabolism of the sugar L-arabinose 1,2,3]. [1]. 9600837. Arm-domain interactions in AraC. Saviola B, Seabold R, Schleif RF;. J Mol Biol 1998;278:539-548. [2]. 11286551. Mapping arm-DNA-binding domain interactions in AraC. Wu M, Schleif R;. J Mol Biol. 2001;307:1001-1009. [3]. 12596232. AraC protein: a love-hate relationship. Schleif R;. Bioessays. 2003;25:274-282. (from Pfam)

Date:

2024-10-16

Date:

2024-08-14

In the absence of arabinose, the N-terminal arm of AraC binds to the DNA binding domain (Pfam:PF00165) and helps to hold the two DNA binding domains in a relative orientation that favours DNA looping. In the presence of arabinose, the arms bind over the arabinose on the dimerisation domain, thus freeing the DNA-binding domains. The freed DNA-binding domains are then able to assume a conformation suitable for binding to the adjacent DNA sites that are utilised when AraC activates transcription, and hence AraC ceases looping the DNA when arabinose is added [1-2]. [1]. 9600836. Apo-AraC actively seeks to loop. Seabold RR, Schleif RF;. J Mol Biol 1998;278:529-538. [2]. 9600837. Arm-domain interactions in AraC. Saviola B, Seabold R, Schleif RF;. J Mol Biol 1998;278:539-548. (from Pfam)

Date:

2024-10-16

AraC family transcriptional regulator containing an AraC family HTH domain and an N-terminal arabinose binding domain, may regulate the expression of genes with diverse biological functions including metabolism, stress response, and virulence.

Date:

2022-08-31