المؤلفون: Hallett, Stephen T, Campbell Harry, Isabella, Schellenberger, Pascale, Zhou, Lihong, Cronin, Nora B, Baxter, Jonathan, Etheridge, Thomas J, Murray, Johanne M, Oliver, Antony W

الوصف: The Smc5/6 complex plays an essential role in the resolution of recombination intermediates formed during mitosis or meiosis, or as a result of the cellular response to replication stress. It also functions as a restriction factor preventing viral replication. Here, we report the cryogenic EM (cryo-EM) structure of the six-subunit budding yeast Smc5/6 holo-complex, reconstituted from recombinant proteins expressed in insect cells – providing both an architectural overview of the entire complex and an understanding of how the Nse1/3/4 subcomplex binds to the hetero-dimeric SMC protein core. In addition, we demonstrate that a region within the head domain of Smc5, equivalent to the ‘W-loop’ of Smc4 or ‘F-loop’ of Smc1, mediates an important interaction with Nse1. Notably, mutations that alter the surface-charge profile of the region of Nse1 which accepts the Smc5-loop, lead to a slow-growth phenotype and a global reduction in the chromatin-associated fraction of the Smc5/6-complex, as judged by single molecule localisation microscopy experiments in live yeast. Moreover, when taken together, our data indicates functional equivalence between the structurally unrelated KITE and HAWK accessory subunits associated with SMC complexes.

وصف الملف: application/pdf

العلاقة: http://sro.sussex.ac.uk/id/eprint/107236/4/gkac692.pdfTest; Hallett, Stephen T, Campbell Harry, Isabella, Schellenberger, Pascale, Zhou, Lihong, Cronin, Nora B, Baxter, Jonathan, Etheridge, Thomas J, Murray, Johanne M and Oliver, Antony W (2022) Cryo-EM Structure of the Smc5/6 holocomplex. Nucleic Acids Research, 50 (16). pp. 9505-9520. ISSN 0305-1048

الإتاحة: https://doi.org/10.1093/nar/gkac692Test
http://sro.sussex.ac.uk/id/eprint/107236Test/
http://sro.sussex.ac.uk/id/eprint/107236/4/gkac692.pdfTest

المؤلفون: Hallett, Stephen T, Schellenberger, Pascale, Zhou, Lihong, Beuron, Fabienne, Morris, Ed, Murray, Johanne M, Oliver, Antony W

الوصف: The multi-component Smc5/6 complex plays a critical role in the resolution of recombination intermediates formed during mitosis and meiosis, and in the cellular response to replication stress. Using recombinant proteins, we have reconstituted a series of defined Saccharomyces cerevisiae Smc5/6 complexes, visualised them by negative stain electron microscopy, and tested their ability to function as an ATPase. We find that only the six protein ‘holo-complex’ is capable of turning over ATP and that its activity is significantly increased by the addition of double-stranded DNA to reaction mixes. Furthermore, stimulation is wholly dependent on functional ATP-binding pockets in both Smc5 and Smc6. Importantly, we demonstrate that budding yeast Nse5/6 acts as a negative regulator of Smc5/6 ATPase activity, binding to the head-end of the complex to suppress turnover, irrespective of the DNA-bound status of the complex.

وصف الملف: application/pdf

العلاقة: http://sro.sussex.ac.uk/id/eprint/98318/1/gkab234.pdfTest; Hallett, Stephen T, Schellenberger, Pascale, Zhou, Lihong, Beuron, Fabienne, Morris, Ed, Murray, Johanne M and Oliver, Antony W (2021) Nse5/6 is a negative regulator of the ATPase activity of the Smc5/6 complex. Nucleic Acids Research, 49 (8). pp. 4534-4549. ISSN 0305-1048

الإتاحة: https://doi.org/10.1093/nar/gkab234Test
http://sro.sussex.ac.uk/id/eprint/98318Test/
http://sro.sussex.ac.uk/id/eprint/98318/1/gkab234.pdfTest

المؤلفون: Hallett, Stephen T, Pastok, Martyna W, Morgan, R Marc L, Wittner, Anita, Blundell, Katie L I M, Felletar, Ildiko, Wedge, Stephen R, Prodromou, Chrisostomos, Noble, Martin E M, Pearl, Laurence H, Endicott, Jane A

الوصف: Selective recruitment of protein kinases to the Hsp90 system is mediated by the adaptor co-chaperone Cdc37. We show that assembly of CDK4 and CDK6 into protein complexes is differentially regulated by the Cdc37-Hsp90 system. Like other Hsp90 kinase clients, binding of CDK4/6 to Cdc37 is blocked by ATP-competitive inhibitors. Cdc37-Hsp90 relinquishes CDK6 to D3- and virus-type cyclins and to INK family CDK inhibitors, whereas CDK4 is relinquished to INKs but less readily to cyclins. p21CIP1 and p27KIP1 CDK inhibitors are less potent than the INKs at displacing CDK4 and CDK6 from Cdc37. However, they cooperate with the D-type cyclins to generate CDK4/6-containing ternary complexes that are resistant to cyclin D displacement by Cdc37, suggesting a molecular mechanism to explain the assembly factor activity ascribed to CIP/KIP family members. Overall, our data reveal multiple mechanisms whereby the Hsp90 system may control formation of CDK4- and CDK6-cyclin complexes under different cellular conditions.

وصف الملف: application/pdf

العلاقة: http://sro.sussex.ac.uk/id/eprint/70934/1/mmc2.pdfTest; Hallett, Stephen T, Pastok, Martyna W, Morgan, R Marc L, Wittner, Anita, Blundell, Katie L I M, Felletar, Ildiko, Wedge, Stephen R, Prodromou, Chrisostomos, Noble, Martin E M, Pearl, Laurence H and Endicott, Jane A (2017) Differential regulation of G1 CDK complexes by the Hsp90-Cdc37 chaperone system. Cell Reports, 21 (5). pp. 1386-1398. ISSN 2211-1247

الإتاحة: http://sro.sussex.ac.uk/id/eprint/70934Test/
http://sro.sussex.ac.uk/id/eprint/70934/1/mmc2.pdfTest
http://www.sciencedirect.com/science/article/pii/S2211124717314894Test

المؤلفون: Hallett, Stephen T., Pastok, Martyna W., Morgan, R. Marc L., Wittner, Anita, Blundell, Katie L.I.M., Felletar, Ildiko, Wedge, Stephen R., Prodromou, Chrisostomos, Noble, Martin E.M., Pearl, Laurence H., Endicott, Jane A.

المساهمون: MRC, CRUK, Wellcome Trust

المصدر: Cell Reports ; volume 21, issue 5, page 1386-1398 ; ISSN 2211-1247

مصطلحات موضوعية: General Biochemistry, Genetics and Molecular Biology

الإتاحة: https://doi.org/10.1016/j.celrep.2017.10.042Test
https://api.elsevier.com/content/article/PII:S2211124717314894?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S2211124717314894?httpAccept=text/plainTest

المؤلفون: Hallett, Stephen T, Campbell Harry, Isabella, Schellenberger, Pascale, Zhou, Lihong, Cronin, Nora B, Baxter, Jonathan, Etheridge, Thomas J, Murray, Johanne M, Oliver, Antony W

المصدر: Nucleic Acids Research; 9/9/2022, Vol. 50 Issue 16, p9505-9520, 16p

المؤلفون: Hallett, Stephen T., Schellenberger, Pascale, Lihong Zhou, Beuron, Fabienne, Morris, Ed, Murray, Johanne M., Oliver, Antony W.

المصدر: Nucleic Acids Research; 5/7/2021, Vol. 49 Issue 8, p4534-4549, 16p, 3 Diagrams, 1 Chart, 4 Graphs