1KXU

CYCLIN H, A POSITIVE REGULATORY SUBUNIT OF CDK ACTIVATING KINASE

Summary for 1KXU

• Entry DOI: 10.2210/pdb1kxu/pdb
• Descriptor: CYCLIN H (2 entities in total)
• Functional Keywords: regulatory protein, cyclin, cell cycle, cell division, nuclear protein, alpha-helical structure
• Biological source: Homo sapiens (human)
• Cellular location: Nucleus: P51946
• Total number of polymer chains: 1
• Total formula weight: 38886.75

Authors

Kim, K.K.,Chamberin, H.M.,Morgan, D.O.,Kim, S.-H. (deposition date: 1996-08-08, release date: 1997-01-27, Last modification date: 2024-02-14)

Primary citation

Kim, K.K.,Chamberlin, H.M.,Morgan, D.O.,Kim, S.H.
Three-dimensional structure of human cyclin H, a positive regulator of the CDK-activating kinase.
Nat.Struct.Biol., 3:849-855, 1996

PubMed Abstract: Cyclin-dependent kinases (CDKs), which play a key role in cell cycle control, are activated by the CDK activating kinase (CAK), which activates cyclin-bound CDKs by phosphorylation at a specific threonine residue. Vertebrate CAK contains two key components: a kinase subunit with homology to its substrate CDKs and a regulatory subunit with homology to cyclins. We have determined the X-ray crystal structure of the regulatory subunit of CAK, cyclin H, at 2.6 A resolution. Cyclin H contains two alpha-helical core domains with a fold similar to that of cyclin A, a regulatory subunit of CAK substrate CDK2, and of TFIIB, a transcription factor. Outside of the core domains, the N- and C-terminal regions of the three structures are completely different. The conformational differences between cyclin H and A structures may reflect functional differences between the two cyclins.

PubMed: 8836101
DOI: 10.1038/nsb1096-849

Experimental method

X-RAY DIFFRACTION (2.6 Å)