46 of 56
This colorful ribbon diagram reveals the structure of HetR, a protein that serves as an essential regulator in the cellular development of cyanobacteria. Cyanobacteria, also called “blue-green algae," are unique creatures that can photosynthesize energy from sunlight. Scientists think that long-ago cyanobacteria colonies tipped the composition of the Earth’s atmosphere towards oxygen, allowing all kinds of life to blossom, including us.
HetR is an essential regulator of heterocyst development in cyanobacteria, initiating a cascade that ultimately is responsible for the activation of more than a thousand genes It binds to a 17-base pair DNA palindrome upstream of the hetP gene.The protein is a dimer comprised of a central DNA-binding unit containing the N-terminal regions of the two subunits organized with two HTH motifs; two globular flaps extending in opposite directions; and a hood over the central core formed from the C-terminal subdomains.
Submitted by: Michelle Radford
Research by: Youngchang Kim, Grazyna Joachimiak, T. Andrew Binkowski, Rongguang Zhang, Andrzej Joachimiak (Argonne)
Zi Ye, Robert Haselkorn, Piotr Gornicki (University of Chicago)
Wolfgang Hess (University of Freiburg)
Sean Callahan (University of Hawaii)
Kim Y, Joachimiak G, Ye Z, Binkowski TA, Zhang R, Gornicki P, Callahan SM, Hess WR, Haselkorn R, Joachimiak A. (2011) Structure of transcription factor HetR required for heterocyst differentiation in cyanobacteria. Proc. Natl. Acad. Sci. , Jun 21;108(25), 10109-14