| Structural highlights
1h28 is a 6 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | NonStd Res: | |
| Related: | 1aq1, 1b38, 1b39, 1buh, 1ckp, 1di8, 1dm2, 1e1v, 1e1x, 1e9h, 1f5q, 1fin, 1fq1, 1fvt, 1fvv, 1g5s, 1gih, 1gii, 1gij, 1gy3, 1gz8, 1h00, 1h01, 1h06, 1h07, 1h08, 1h0u, 1h0v, 1h0w, 1h1p, 1h1q, 1h1r, 1h1s, 1h24, 1h25, 1h26, 1h27, 1hck, 1hcl, 1jst, 1jsu, 1jsv, 1jvp, 1ke5, 1ke6, 1ke7, 1ke8, 1ke9, 1qmz |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum |
Function
[RBL1_HUMAN] Key regulator of entry into cell division. Directly involved in heterochromatin formation by maintaining overall chromatin structure and, in particular, that of constitutive heterochromatin by stabilizing histone methylation. Recruits and targets histone methyltransferases SUV420H1 and SUV420H2, leading to epigenetic transcriptional repression. Controls histone H4 'Lys-20' trimethylation. Probably acts as a transcription repressor by recruiting chromatin-modifying enzymes to promoters. Potent inhibitor of E2F-mediated trans-activation. Forms a complex with adenovirus E1A and with SV40 large T antigen. May bind and modulate functionally certain cellular proteins with which T and E1A compete for pocket binding. May act as a tumor suppressor. [CCNA2_HUMAN] Essential for the control of the cell cycle at the G1/S (start) and the G2/M (mitosis) transitions.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Progression through S phase of the eukaryotic cell cycle is regulated by the action of the cyclin dependent protein kinase 2 (CDK2) in association with cyclin A. CDK2/cyclin A phosphorylates numerous substrates. Substrate specificity often employs a dual recognition strategy in which the sequence flanking the phospho-acceptor site (Ser.Pro.X.Arg/Lys) is recognized by CDK2, while the cyclin A component of the complex contains a hydrophobic site that binds Arg/Lys.X.Leu ("RXL" or "KXL") substrate recruitment motifs. To determine additional sequence specificity motifs around the RXL sequence, we have performed X-ray crystallographic studies at 2.3 A resolution and isothermal calorimetry measurements on complexes of phospho-CDK2/cyclin A with a recruitment peptide derived from E2F1 and with shorter 11-mer peptides from p53, pRb, p27, E2F1, and p107. The results show that the cyclin recruitment site accommodates a second hydrophobic residue either immediately C-terminal or next adjacent to the leucine of the "RXL" motif and that this site makes important contributions to the recruitment peptide recognition. The arginine of the RXL motif contacts a glutamate, Glu220, on the cyclin. In those substrates that contain a KXL motif, no ionic interactions are observed with the lysine. The sequences N-terminal to the "RXL" motif of the individual peptides show no conservation, but nevertheless make common contacts to the cyclin through main chain interactions. Thus, the recruitment site is able to recognize diverse but conformationally constrained target sequences. The observations have implications for the further identification of physiological substrates of CDK2/cyclin A and the design of specific inhibitors.
Specificity determinants of recruitment peptides bound to phospho-CDK2/cyclin A.,Lowe ED, Tews I, Cheng KY, Brown NR, Gul S, Noble ME, Gamblin SJ, Johnson LN Biochemistry. 2002 Dec 31;41(52):15625-34. PMID:12501191[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Lowe ED, Tews I, Cheng KY, Brown NR, Gul S, Noble ME, Gamblin SJ, Johnson LN. Specificity determinants of recruitment peptides bound to phospho-CDK2/cyclin A. Biochemistry. 2002 Dec 31;41(52):15625-34. PMID:12501191
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