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Lv Y, Du Y, Li K, Ma X, Wang J, Du T, Ma Y, Teng Y, Tang W, Ma R, Wu J, Wu J, Feng J. The FACT-targeted drug CBL0137 enhances the effects of rituximab to inhibit B-cell non-Hodgkin's lymphoma tumor growth by promoting apoptosis and autophagy. Cell Commun Signal 2023; 21:16. [PMID: 36691066 PMCID: PMC9869543 DOI: 10.1186/s12964-022-01031-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 12/25/2022] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Aggressive B-cell non-Hodgkin's lymphoma (B-NHL) patients often develop drug resistance and tumor recurrence after conventional immunochemotherapy, for which new treatments are needed. METHODS We investigated the antitumor effects of CBL0137. In vitro, cell proliferation was assessed by CCK-8 and colony formation assay. Flow cytometry was performed to analyze cell cycle progression, apoptosis, mitochondrial depolarization, and reactive oxygen species (ROS) production. Autophagy was detected by transmission electron microscopy and mGFP-RFP-LC3 assay, while western blotting was employed to detect proteins involved in apoptosis and autophagy. RNA-sequencing was conducted to analyze the transcription perturbation after CBL0137 treatment in B-NHL cell lines. Finally, the efficacy and safety of CBL0137, rituximab, and their combination were tested in vivo. RESULTS CBL0137, a small molecule anticancer agent that has significant antitumor effects in B-NHL. CBL0137 sequesters the FACT (facilitates chromatin transcription) complex from chromatin to produce cytotoxic effects in B-NHL cells. In addition, we discovered novel anticancer mechanisms of CBL0137. CBL0137 inhibited human B-NHL cell proliferation by inducing cell cycle arrest in S phase via the c-MYC/p53/p21 pathway. Furthermore, CBL0137 triggers ROS generation and induces apoptosis and autophagy in B-NHL cells through the ROS-mediated PI3K/Akt/mTOR and MAPK signaling pathways. Notably, a combination of CBL0137 and rituximab significantly suppressed B-NHL tumor growth in subcutaneous models, consistent with results at the cellular level in vitro. CONCLUSIONS CBL0137 has potential as a novel approach for aggressive B-NHL, and its combination with rituximab can provide new therapeutic options for patients with aggressive B-NHL. Video Abstract.
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Affiliation(s)
- Yan Lv
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Yuxin Du
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China.
| | - Kening Li
- Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, Jiangsu Province, China
| | - Xiao Ma
- Department of General Surgery, The Affiliated Zhongda Hospital of Southeast University, 87 Dingjiaqiao, Nanjing, 210009, Jiangsu Province, China
| | - Juan Wang
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Tongde Du
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Yuxin Ma
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Yue Teng
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Weiyan Tang
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Rong Ma
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Jianqiu Wu
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Jianzhong Wu
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China
| | - Jifeng Feng
- Nanjing Medical University Affiliated Cancer Hospital, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, 42 Baiziting, Nanjing, 210009, Jiangsu Province, China.
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Zhang W, Zeng F, Liu Y, Shao C, Li S, Lv H, Shi Y, Niu L, Teng M, Li X. Crystal Structure of Human SSRP1 Middle Domain Reveals a Role in DNA Binding. Sci Rep 2015; 5:18688. [PMID: 26687053 PMCID: PMC4685450 DOI: 10.1038/srep18688] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 11/23/2015] [Indexed: 02/06/2023] Open
Abstract
SSRP1 is a subunit of the FACT complex, an important histone chaperone required for transcriptional regulation, DNA replication and damage repair. SSRP1 also plays important roles in transcriptional regulation independent of Spt16 and interacts with other proteins. Here, we report the crystal structure of the middle domain of SSRP1. It consists of tandem pleckstrin homology (PH) domains. These domains differ from the typical PH domain in that PH1 domain has an extra conserved βαβ topology. SSRP1 contains the well-characterized DNA-binding HMG-1 domain. Our studies revealed that SSRP1-M can also participate in DNA binding, and that this binding involves one positively charged patch on the surface of the structure. In addition, SSRP1-M did not bind to histones, which was assessed through pull-down assays. This aspect makes the protein different from other related proteins adopting the double PH domain structure. Our studies facilitate the understanding of SSRP1 and provide insights into the molecular mechanisms of interaction with DNA and histones of the FACT complex.
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Affiliation(s)
- Wenjuan Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Fuxing Zeng
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Yiwei Liu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Chen Shao
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Sai Li
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Hui Lv
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Yunyu Shi
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Liwen Niu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Maikun Teng
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
| | - Xu Li
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China.,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui, 230026, People's Republic of China
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Luo CW, Wu CC, Ch'ang HJ. Radiation sensitization of tumor cells induced by shear stress: the roles of integrins and FAK. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:2129-37. [PMID: 24946134 DOI: 10.1016/j.bbamcr.2014.06.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 05/27/2014] [Accepted: 06/09/2014] [Indexed: 10/25/2022]
Abstract
Recent studies revealed that the interstitial fluid flow in and around tumor tissue not only played an important role in delivering anticancer agents, but also affected the microenvironment, mostly hypoxia, in modulating tumor radio-sensitivity. The current study investigated the hypoxia-independent mechanisms of flow-induced shear stress in sensitizing tumors to radiation. Colon cancer cells were seeded onto glass slides pre-coated with fibronectin. A parallel-plate flow chamber system was used to impose fluid shear stress. Cell proliferation, apoptosis and colony assays were measured after shear stress and/or radiation. Cell cycle analysis and immunoblots of cell adhesion signal molecules were evaluated. The effect of shear stress was reversed by modulating integrin β1 or FAK. Shear stress of 12dyne/cm(2) for 24h, but not 3h, enhanced the radiation induced cytotoxicity to colon cancer cells. Protein expression of FAK was significantly down-regulated but not transcriptionally suppressed. By modulating integrin β1 and FAK expression, we demonstrated that shear stress enhanced tumor radiosensitivity by regulating integrin β1/FAK/Akt as well as integrin β1/FAK/cortactin pathways. Shear stress in combination with radiation might regulate integrins signaling by recruiting and activating caspases 3/8 for FAK cleavage followed by ubiquitin-mediated proteasomal degradation. Shear stress enhanced the radiation toxicity to colon cancer cells through suppression of integrin signaling and protein degradation of FAK. The results of our study provide a strong rationale for cancer treatment that combines between radiation and strategy in modulating tumor interstitial fluid flow.
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Affiliation(s)
- Chi-Wen Luo
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan
| | - Chia-Ching Wu
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hui-Ju Ch'ang
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan; Department of Radiation Oncology, National Cheng Kung University Hospital, Tainan, Taiwan.
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Reales-Calderón JA, Sylvester M, Strijbis K, Jensen ON, Nombela C, Molero G, Gil C. Candida albicans induces pro-inflammatory and anti-apoptotic signals in macrophages as revealed by quantitative proteomics and phosphoproteomics. J Proteomics 2013; 91:106-35. [DOI: 10.1016/j.jprot.2013.06.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 06/16/2013] [Indexed: 12/11/2022]
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Caspase-dependent regulation of the ubiquitin-proteasome system through direct substrate targeting. Proc Natl Acad Sci U S A 2013; 110:14284-9. [PMID: 23940367 DOI: 10.1073/pnas.1306179110] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Drosophila inhibitor of apoptosis (IAP) 1 (DIAP1) is an E3 ubiquitin ligase that regulates apoptosis in flies, in large part through direct inhibition and/or ubiquitinylation of caspases. IAP antagonists, such as Reaper, Hid, and Grim, are thought to induce cell death by displacing active caspases from baculovirus IAP repeat domains in DIAP1, but can themselves become targets of DIAP1-mediated ubiquitinylation. Herein, we demonstrate that Grim self-associates in cells and is ubiquitinylated by DIAP1 at Lys136 in an UbcD1-dependent manner, resulting in its rapid turnover. K48-linked ubiquitin chains are added almost exclusively to BIR2-bound Grim as a result of its structural proximity to DIAP1's RING domain. However, active caspases can simultaneously cleave Grim at Asp132, removing the lysine necessary for ubiquitinylation as well as any existing ubiquitin conjugates. Cleavage therefore enhances the stability of Grim and initiates a feed-forward caspase amplification loop, resulting in greater cell death. In summary, Grim is a caspase substrate whose cleavage promotes apoptosis by limiting, in a target-specific fashion, its ubiquitinylation and turnover by the proteasome.
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O'Connell BC, Adamson B, Lydeard JR, Sowa ME, Ciccia A, Bredemeyer AL, Schlabach M, Gygi SP, Elledge SJ, Harper JW. A genome-wide camptothecin sensitivity screen identifies a mammalian MMS22L-NFKBIL2 complex required for genomic stability. Mol Cell 2010; 40:645-57. [PMID: 21055985 DOI: 10.1016/j.molcel.2010.10.022] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/20/2010] [Accepted: 10/18/2010] [Indexed: 10/18/2022]
Abstract
Replication stress involving collision of replisomes with camptothecin (CPT)-stabilized DNA-Topoisomerase I adducts activates an ATR-dependent pathway to promote repair by homologous recombination. To identify human genes that protect cells from such replication stress, we performed a genome-wide CPT sensitivity screen. Among numerous candidate genes are two previously unstudied proteins: the ankyrin repeat protein NFKBIL2 and C6ORF167 (MMS22L), distantly related to yeast replication stress regulator Mms22p. MMS22L and NFKBIL2 interact with each other and with FACT (facilitator of chromatin transcription) and MCM (minichromosome maintenance) complexes. Cells depleted of NFKBIL2 or MMS22L are sensitive to DNA-damaging agents, load phosphorylated RPA onto chromatin in a CTIP-dependent manner, activate the ATR/ATRIP-CHK1 and double-strand break repair signaling pathways, and are defective in HR. This study identifies MMS22L-NFKBIL2 as components of the replication stress control pathway and provides a resource for discovery of additional components of this pathway.
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Kumari A, Mazina OM, Shinde U, Mazin AV, Lu H. A role for SSRP1 in recombination-mediated DNA damage response. J Cell Biochem 2009; 108:508-18. [PMID: 19639603 DOI: 10.1002/jcb.22280] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A possible role for structure-specific recognition protein 1 (SSRP1) in replication-associated repair processes has previously been suggested based on its interaction with several DNA repair factors and the replication defects observed in SSRP1 mutants. In this study, we investigated the potential role of SSRP1 in association with DNA repair mediated by homologous recombination (HR), one of the pathways involved in repairing replication-associated DNA damage, in mammalian cells. Surprisingly, over-expression of SSRP1 reduced the number of hprt(+) recombinants generated via HR both spontaneously and upon hydroxyurea (HU) treatment, whereas knockdown of SSRP1 resulted in an increase of HR events in response to DNA double-strand break formation. In correlation, we found that the depletion of SSRP1 in HU-treated human cells elevated the number of Rad51 and H2AX foci, while over-expression of the wild-type SSRP1 markedly reduced HU-induced Rad51 foci formation. We also found that SSRP1 physically interacts with a key HR repair protein, Rad54 both in vitro and in vivo. Further, branch migration studies demonstrated that SSRP1 inhibits Rad54-promoted branch migration of Holliday junctions in vitro. Taken together, our data suggest a functional role for SSRP1 in spontaneous and replication-associated DNA damage response by suppressing avoidable HR repair events.
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Affiliation(s)
- Anuradha Kumari
- Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, Oregon 97239, USA
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Structure-specific recognition protein 1 facilitates microtubule growth and bundling required for mitosis. Mol Cell Biol 2009; 30:935-47. [PMID: 19995907 DOI: 10.1128/mcb.01379-09] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tight regulation of microtubule (MT) dynamics is essential for proper chromosome movement during mitosis. Here we show, using mammalian cells, that structure-specific recognition protein 1 (SSRP1) is a novel regulator of MT dynamics. SSRP1 colocalizes with the spindle and midbody MTs, and associates with MTs both in vitro and in vivo. Purified SSRP1 facilitates tubulin polymerization and MT bundling in vitro. Knockdown of SSRP1 inhibits the growth of MTs and leads to disorganized spindle structures, reduction of K-fibers and midbody fibers, disrupted chromosome movement, and attenuated cytokinesis in vivo. These results demonstrate that SSRP1 is crucial for MT growth and spindle assembly during mitosis.
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Jenkins LMM, Mazur SJ, Rossi M, Gaidarenko O, Xu Y, Appella E. Quantitative proteomics analysis of the effects of ionizing radiation in wild type and p53 K317R knock-in mouse thymocytes. Mol Cell Proteomics 2008; 7:716-27. [PMID: 18178582 DOI: 10.1074/mcp.m700482-mcp200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The tumor suppressor protein p53 is a sequence-specific transcription factor that has crucial roles in apoptosis, cell cycle arrest, cellular senescence, and DNA repair. Following exposure to a variety of stresses, p53 becomes post-translationally modified with concomitant increases in activity and stability. To better understand the role of acetylation of Lys-317 in mouse p53, the effect of ionizing radiation (IR) on the thymocytes of p53(K317R) knock-in mice was studied at the global level. Using cleavable ICAT quantitative mass spectrometry, the effect of IR on protein levels in either the wild type or p53(K317R) thymocytes was determined. We found 102 proteins to be significantly affected by IR in the wild type thymocytes, including several whose expression has been shown to be directly regulated by p53. When the effects of IR in the wild type and p53(K317R) samples were compared, 46 proteins were found to be differently affected (p < 0.05). The p53(K317R) mutation has widespread effects on specific protein levels following IR, including the levels of proteins involved in apoptosis, transcription, and translation. Pathway analysis of the differently regulated proteins suggests an increase in p53 activity in the p53(K317R) thymocytes as well as a decrease in tumor necrosis factor alpha signaling. These results suggest that acetylation of Lys-317 modulates the functions of p53 and influences the cross-talk between the DNA damage response and other signaling pathways.
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Affiliation(s)
- Lisa M Miller Jenkins
- Laboratory of Cell Biology, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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Li Y, Zeng SX, Landais I, Lu H. Human SSRP1 has Spt16-dependent and -independent roles in gene transcription. J Biol Chem 2007; 282:6936-45. [PMID: 17209051 DOI: 10.1074/jbc.m603822200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The facilitating chromatin transcription (FACT) complex, a heterodimer of SSRP1 and Spt16, has been shown to regulate transcription elongation through a chromatin template in vitro and on specific genes in cells. However, its global role in transcription regulation in human cells remains largely elusive. We conducted spotted microarray analyses using arrays harboring 8308 human genes to assess the gene expression profile after knocking down SSRP1 or Spt16 levels in human non-small cell lung carcinoma (H1299) cells. Although the changes of these transcripts were surprisingly subtle, there were approximately 170 genes whose transcript levels were either reduced or induced >1.5-fold. Approximately 106 genes with >1.2-fold change at the level of transcripts were the common targets of both SSRP1 and Spt16 ( approximately 1.3%). A subset of genes was regulated by SSRP1 independent of Spt16. Further analyses of some of these genes not only verified this observation but also identified the serum-responsive gene, egr1, as a novel target for both SSRP1 and Spt16. We further showed that SSRP1 and Spt16 are important for the progression of elongation RNA pol II on the egr1 gene. These results suggest that SSRP1 has Spt16-dependent and -independent roles in regulating gene transcription in human cells.
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Affiliation(s)
- Yanping Li
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon 97239, USA
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