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Medicine and Health Sciences Commons

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Department of Biochemistry and Molecular Biology Faculty Papers

Series

2014

Thomas Jefferson University

Articles 1 - 3 of 3

Full-Text Articles in Medicine and Health Sciences

Parp-2 And Parp-3 Are Selectively Activated By 5' Phosphorylated Dna Breaks Through An Allosteric Regulatory Mechanism Shared With Parp-1., Marie-France Langelier, Amanda A Riccio, John M Pascal Aug 2014

Parp-2 And Parp-3 Are Selectively Activated By 5' Phosphorylated Dna Breaks Through An Allosteric Regulatory Mechanism Shared With Parp-1., Marie-France Langelier, Amanda A Riccio, John M Pascal

Department of Biochemistry and Molecular Biology Faculty Papers

PARP-1, PARP-2 and PARP-3 are DNA-dependent PARPs that localize to DNA damage, synthesize poly(ADP-ribose) (PAR) covalently attached to target proteins including themselves, and thereby recruit repair factors to DNA breaks to increase repair efficiency. PARP-1, PARP-2 and PARP-3 have in common two C-terminal domains-Trp-Gly-Arg (WGR) and catalytic (CAT). In contrast, the N-terminal region (NTR) of PARP-1 is over 500 residues and includes four regulatory domains, whereas PARP-2 and PARP-3 have smaller NTRs (70 and 40 residues, respectively) of unknown structural composition and function. Here, we show that PARP-2 and PARP-3 are preferentially activated by DNA breaks harboring a 5' phosphate …


Multisite Phosphorylation Of The Sum1 Transcriptional Repressor By S-Phase Kinases Controls Exit From Meiotic Prophase In Yeast., Daniel Corbi, Sham Sunder, Michael Weinreich, Aikaterini Skokotas, Erica S Johnson, Edward Winter Jun 2014

Multisite Phosphorylation Of The Sum1 Transcriptional Repressor By S-Phase Kinases Controls Exit From Meiotic Prophase In Yeast., Daniel Corbi, Sham Sunder, Michael Weinreich, Aikaterini Skokotas, Erica S Johnson, Edward Winter

Department of Biochemistry and Molecular Biology Faculty Papers

Activation of the meiotic transcription factor Ndt80 is a key regulatory transition in the life cycle of Saccharomyces cerevisiae because it triggers exit from pachytene and entry into meiosis. The NDT80 promoter is held inactive by a complex containing the DNA-binding protein Sum1 and the histone deacetylase Hst1. Meiosis-specific phosphorylation of Sum1 by the protein kinases Cdk1, Ime2, and Cdc7 is required for NDT80 expression. Here, we show that the S-phase-promoting cyclin Clb5 activates Cdk1 to phosphorylate most, and perhaps all, of the 11 minimal cyclin-dependent kinase (CDK) phospho-consensus sites (S/T-P) in Sum1. Nine of these sites can individually promote …


The P53-Induced Factor Ei24 Inhibits Nuclear Import Through An Importin Β-Binding-Like Domain., Kim G Lieu, Eun-Hee Shim, Jinling Wang, Ravi K Lokareddy, Tao Tao, Gino Cingolani, Gerard P Zambetti, David A Jans May 2014

The P53-Induced Factor Ei24 Inhibits Nuclear Import Through An Importin Β-Binding-Like Domain., Kim G Lieu, Eun-Hee Shim, Jinling Wang, Ravi K Lokareddy, Tao Tao, Gino Cingolani, Gerard P Zambetti, David A Jans

Department of Biochemistry and Molecular Biology Faculty Papers

The etoposide-induced protein Ei24 was initially identified as a p53-responsive, proapoptotic factor, but no clear function has been described. Here, we use a nonbiased proteomics approach to identify members of the importin (IMP) family of nuclear transporters as interactors of Ei24 and characterize an IMPβ-binding-like (IBBL) domain within Ei24. We show that Ei24 can bind specifically to IMPβ1 and IMPα2, but not other IMPs, and use a mutated IMPβ1 derivative to show that Ei24 binds to the same site on IMPβ1 as the IMPα IBB. Ectopic expression of Ei24 reduced the extent of IMPβ1- or IMPα/β1-dependent nuclear protein import specifically, …