Structural studies of the I-kappa-B kinase complex

Devin Drew

Appointment Period: 1999-2001, Grant Years: [15,16]

The I-kappa-B kinase complex (IKKc) serves as a junction integrating the majority of signals which activate the transcription factor NF-kappa-B in the mammalian inflammatory and immune responses. An observed correlation between the constitutive activation of this transcription factor and oncogenesis makes sense when the normal cellular responses are considered. NF-kappa-B regulates genes important in apoptosis and cell proliferation. A structural and biochemical understanding of IKKc regulation is the goal my work in the lab.

The IKKc is made up of two kinase domains containing the polypeptides IKK-alpha and beta, as well as a helical subunit termed IKK-gamma. With the aim of crystallizing and determining an atomic resolution structure of the IKKc, I am expressing different segments of IKK-beta and IKK-gamma in bacteria and virus-infected insect cell cultures. I have successfully purified a complex containing IKK-beta with a portion of IKK-gamma and performed crystallization screens. I am continuously working to improve this system to allow a more rigorous search of crystal conditions. I have also purified large quantities of a 130 amino acid region of IKK-gamma which is important for binding to the catalytic domains of the IKKc. Crystallization trials of this protein are currently underway. Additionally, I am undertaking biochemical and biophysical experiments to study the nature of the beta:gamma interaction.

PUBLICATIONS (resulting from this training, and some recent ones)

Wriggers W, Agrawal RK, Drew DL, McCammon A, Frank J.(2000) Domain motions of EF-G bound to the 70S ribosome: insights from a hand-shaking between multi-resolution structures. Biophys J. 79:1670-8.

Sola M, Drew DL, Blanco AG, Gomis-Ruth FX, Coll M. (2006) The cofactor-induced pre-active conformation in PhoB. Acta Crystallogr D Biol Crystallogr. 62:1046-57.