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Fu X, Li P, Zhou Q, He R, Wang G, Zhu S, Bagheri A, Kupfer G, Pei H, Li J. Mechanism of PARP inhibitor resistance and potential overcoming strategies. Genes Dis 2024; 11:306-320. [PMID: 37588193 PMCID: PMC10425807 DOI: 10.1016/j.gendis.2023.02.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/27/2023] [Accepted: 02/02/2023] [Indexed: 08/18/2023] Open
Abstract
PARP inhibitors (PARPi) are a kind of cancer therapy that targets poly (ADP-ribose) polymerase. PARPi is the first clinically approved drug to exert synthetic lethality by obstructing the DNA single-strand break repair process. Despite the significant therapeutic effect in patients with homologous recombination (HR) repair deficiency, innate and acquired resistance to PARPi is a main challenge in the clinic. In this review, we mainly discussed the underlying mechanisms of PARPi resistance and summarized the promising solutions to overcome PARPi resistance, aiming at extending PARPi application and improving patient outcomes.
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Affiliation(s)
- Xiaoyu Fu
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Ping Li
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Qi Zhou
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Ruyuan He
- Department of Thoracic Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Guannan Wang
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Shiya Zhu
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Amir Bagheri
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Gary Kupfer
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Huadong Pei
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC 20057, USA
| | - Juanjuan Li
- Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
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Zi F, Li Z, Cheng W, Huang X, Sheng X, Rong W. Novel mutations of the X-linked genes associated with early-onset high myopia in five Chinese families. BMC Med Genomics 2023; 16:223. [PMID: 37749571 PMCID: PMC10521526 DOI: 10.1186/s12920-023-01665-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 09/18/2023] [Indexed: 09/27/2023] Open
Abstract
PURPOSE To report novel pathogenic variants of X-linked genes in five Chinese families with early-onset high myopia (eoHM) by using whole-exome sequencing and analyzing the phenotypic features. METHODS 5 probands with X-linked recessive related eoHM were collected in Ningxia Eye Hospital from January 2021 to June 2022. The probands and their family members received comprehensive ophthalmic examinations,and DNA was abstracted from patients and family members. Whole-exome sequencing was performed on probands to screen the causative variants, and all suspected pathogenic variants were determined by Sanger sequencing and co-segregation analysis was performed on available family members. The pathogenicity of novel variants was predicted using silico analysis and evaluated according to ACMG guidelines. RT-qPCR was used to detect differences in the relative mRNAs expression of candidate gene in mRNAs available with the proband and family members in the pedigree 2. The relationship between genetic variants and clinical features was analyzed. RESULTS All probands were male, and all pedigrees conformed to an X-linked recessive inheritance pattern. They were diagnosed with high myopia at their first visits between 4 and 7 years old. Spherical equivalent ranged between - 6.00D and - 11.00D.The five novel hemizygous variants were found in the probands, containing frameshift deletion variant c.797_801del (p.Val266Alafs*75) of OPN1LW gene in the pedigree 1, nonsense variant c.513G > A (p.Trp171Ter)of RP2 gene in the pedigree 2, missense variant c.98G > T (p.Cys33Phe) of GPR143 gene in the pedigree 3, frameshift deletion variant c.1876_1877del (p.Met626Valfs*22) of FRMD7 gene in the pedigree 4 and inframe deletion variant c.670_ 675del (p.Glu192_ Glu193del) of HMGB3 gene in the pedigree 5. All variants were classified as pathogenic or likely pathogenic by the interpretation principles of HGMD sequence variants and ACMG guidelines. In family 2, RT-qPCR showed that the mRNA expression of RP2 gene was lower in the proband than in other normal family members, indicating that such variant caused an effect on gene function at the mRNA expression level. Further clinical examination showed that pedigrees 1, 2, 3, and 4 were diagnosed as X-linked recessive hereditary eye disease with early-onset high myopia, including quiescent cone dysfunction, retinitis pigmentosa, ocular albinism, and idiopathic congenital nystagmus respectively. The pedigree 5 had eoHM in the right eye and ptosis in both eyes. CONCLUSION In this paper,we are the first to report five novel hemizygous variants in OPN1LW, RP2, GPR143, FRMD7, HMGB3 genes are associated with eoHM. Our study extends the genotypic spectrums for eoHM and better assists ophthalmologists in assessing, diagnosing, and conducting genetic screening for eoHM.
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Affiliation(s)
- Feiyin Zi
- Clinical Medical College, Ningxia Medical University, Yinchuan, 750001, China
| | - Zhen Li
- Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, 936 Huanghe East Road, Jinfeng District, Yinchuan, 750001, China
| | - Wanyu Cheng
- Clinical Medical College, Ningxia Medical University, Yinchuan, 750001, China
| | - Xiaoyu Huang
- Clinical Medical College, Ningxia Medical University, Yinchuan, 750001, China
| | - Xunlun Sheng
- Gansu Aier Ophthalmiology and Optometry Hospital, 1228 Guazhou Road, Qilihe District, Lanzhou, 730050, China.
| | - Weining Rong
- Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, 936 Huanghe East Road, Jinfeng District, Yinchuan, 750001, China.
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Wu Z, Huang Y, Yuan W, Wu X, Shi H, Lu M, Xu A. Expression, tumor immune infiltration, and prognostic impact of HMGs in gastric cancer. Front Oncol 2022; 12:1056917. [PMID: 36568211 PMCID: PMC9780705 DOI: 10.3389/fonc.2022.1056917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 11/07/2022] [Indexed: 12/13/2022] Open
Abstract
Background In the past decade, considerable research efforts on gastric cancer (GC) have been expended, however, little advancement has been made owing to the lack of effective biomarkers and treatment options. Herein, we aimed to examine the levels of expression, mutations, and clinical relevance of HMGs in GC to provide sufficient scientific evidence for clinical decision-making and risk management. Methods GC samples were obtained from The Cancer Genome Atlas (TCGA). University of California Santa Cruz (UCSC) XENA, Human Protein Atlas (HPA), Gene Expression Profiling Interactive Analysis (GEPIA), Kaplan-Meier Plotter, cBioPortal, GeneMANIA, STRING, LinkedOmics, and DAVID databases were employed. The "ggplot2" package in the R software (×64 3.6.3) was used to thoroughly analyze the effects of HMGs. qRT-PCR was performed to assess HMG levels in GC cell lines. Results A total of 375 GC tissues and 32 paraneoplastic tissues were analyzed. The levels of HMGA1, HMGA2, HMGB1, HMGB2, HMGB3, HMGN1, HMGN2, and HMGN4 expression were increased in GC tissues relative to normal gastric tissues. HMGA1, HMGA2, HMGB1, HMGB2, and HMGB3 were highly expressed in GC cell lines. The OS was significantly different in the group showing low expressions of HMGA1, HMGA2, HMGB1, HMGB2, HMGB3, HMGN2, HMGN3, and HMGN5. There was a significant difference in RFS between the groups with low HMGA2, HMGB3, and high HMGN2 expression. The levels of HMGA2, HMGB3, and HMGN1 had a higher accuracy for prediction to distinguish GC from normal tissues (AUC value > 0.9). HMGs were tightly associated with immune infiltration and tumor immune escape and antitumor immunity most likely participates in HMG-mediated oncogenesis in GC. GO and KEGG enrichment analyses showed that HMGs played a vital role in the cell cycle pathway. Conclusions Our results strongly suggest a vital role of HMGs in GC. HMGA2 and HMGB3 could be potential markers for prognostic prediction and treatment targets for GC by interrupting the cell cycle pathway. Our findings might provide renewed perspectives for the selection of prognostic biomarkers among HMGs in GC and may contribute to the determination of the optimal strategy for the treatment of these patients.
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Affiliation(s)
- Zhiheng Wu
- Department of General Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China,Department of General Surgery, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Yang Huang
- Department of General Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China,Department of General Surgery, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Weiwei Yuan
- Department of General Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China,Department of General Surgery, Anhui Public Health Clinical Center, Hefei, Anhui, China
| | - Xiong Wu
- School of Optometry and Ophthalmology and the Eye Hospital, Wenzhou Medical University, PR China, State Key Laboratory of Optometry, Ophthalmology, and Visual Science, Wenzhou, Zhejiang, China
| | - Hui Shi
- Department of Immunology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui, China
| | - Ming Lu
- Department of Immunology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui, China
| | - Aman Xu
- Department of General Surgery, the First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China,Department of General Surgery, Anhui Public Health Clinical Center, Hefei, Anhui, China
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HMGB3 promotes PARP inhibitor resistance through interacting with PARP1 in ovarian cancer. Cell Death Dis 2022; 13:263. [PMID: 35332131 PMCID: PMC8948190 DOI: 10.1038/s41419-022-04670-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 02/11/2022] [Accepted: 02/17/2022] [Indexed: 01/03/2023]
Abstract
Poly (ADP-ribose) polymerase (PARP) inhibitor (PARPi) resistance remains a therapeutic challenge in ovarian cancer. High-mobility group box 3 (HMGB3) plays significant roles in the development of drug resistance of many cancers. However, the function of HMGB3 in PARPi resistance is poorly understood. In the current study, we clarified that HMGB3 was aberrantly overexpressed in high-grade serous ovarian carcinoma (HGSOC) tissues, and high HMGB3 levels indicated shorter overall survival and drug resistance in HGSOC. The overexpression of HMGB3 increased the insensitivity of ovarian cancer to PARPi, whereas HMGB3 knockdown reduced PARPi resistance. Mechanistically, PARP1 was identified as a novel interaction partner of HMGB3, which could be blocked using olaparib and was enhanced upon DNA damage conditions. We further showed that loss of HMGB3 induced PARP1 trapping at DNA lesions and inhibited the PARylation activity of PARP1, resulting in an increased DNA damage response and cell apoptosis. The PARPi-resistant role of HMGB3 was also verified in a xenograft mouse model. In conclusion, HMGB3 promoted PARPi resistance via interacting with PARP1, and the targeted inhibition of HMGB3 might overcome PARPi resistance in ovarian cancer therapy.
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Wen B, Wei YT, Zhao K. The role of high mobility group protein B3 (HMGB3) in tumor proliferation and drug resistance. Mol Cell Biochem 2021; 476:1729-1739. [PMID: 33428061 DOI: 10.1007/s11010-020-04015-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 12/02/2020] [Indexed: 02/07/2023]
Abstract
The high mobility group protein B (HMGB) family (including HMGB1, HMGB2, HMGB3, and HMGB4) can regulate the mechanisms of DNA replication, transcription, recombination, and repair, and act as cytokines to mediate responses to infection, injury, and inflammation. HMGB1/2/3 has a high similarity in sequence and structure, while HMGB4 has no acidic C-terminal tail. Among them, HMGB3 can regulate the self-renewal and differentiation of normal hematopoietic stem cell population, but the decrease of its expression is easy to induce leukemia. Up-regulation of its expression promotes tumor development and chemotherapy resistance through a variety of mechanisms, and non-coding RNA can regulate to promote tumor cell proliferation, invasion, and migration and inhibit cancer cell apoptosis.
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Affiliation(s)
- Bin Wen
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Huichuan District, Zunyi, 563003, Guizhou, P. R. China
| | - Ying-Ting Wei
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Huichuan District, Zunyi, 563003, Guizhou, P. R. China
| | - Kui Zhao
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Huichuan District, Zunyi, 563003, Guizhou, P. R. China.
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High Mobility Group B Proteins, Their Partners, and Other Redox Sensors in Ovarian and Prostate Cancer. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2016:5845061. [PMID: 26682011 PMCID: PMC4670870 DOI: 10.1155/2016/5845061] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 07/27/2015] [Indexed: 01/02/2023]
Abstract
Cancer cells try to avoid the overproduction of reactive oxygen species by metabolic rearrangements. These cells also develop specific strategies to increase ROS resistance and to express the enzymatic activities necessary for ROS detoxification. Oxidative stress produces DNA damage and also induces responses, which could help the cell to restore the initial equilibrium. But if this is not possible, oxidative stress finally activates signals that will lead to cell death. High mobility group B (HMGB) proteins have been previously related to the onset and progressions of cancers of different origins. The protein HMGB1 behaves as a redox sensor and its structural changes, which are conditioned by the oxidative environment, are associated with different functions of the protein. This review describes recent advances in the role of human HMGB proteins and other proteins interacting with them, in cancerous processes related to oxidative stress, with special reference to ovarian and prostate cancer. Their participation in the molecular mechanisms of resistance to cisplatin, a drug commonly used in chemotherapy, is also revised.
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Kenwrick S, Amaya E, Papalopulu N. Pilot morpholino screen in Xenopus tropicalis identifies a novel gene involved in head development. Dev Dyn 2004; 229:289-99. [PMID: 14745953 DOI: 10.1002/dvdy.10440] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The diploid frog X. tropicalis has recently been adopted as a model genetic system, but loss-of-function screens in Xenopus have not yet been performed. We have undertaken a pilot functional knockdown screen in X. tropicalis for genes involved in nervous system development by injecting antisense morpholino (MO) oligos directed against X. tropicalis mRNAs. Twenty-six genes with primary expression in the nervous system were selected as targets based on an expression screen previously conducted in X. laevis. Reproducible phenotypes were observed for six and for four of these, a second MO gave a similar result. One of these genes encodes a novel protein with previously unknown function. Knocking down this gene, designated pinhead, results in severe microcephaly, whereas, overexpression results in macrocephaly. Together with the early embryonic expression in the anterior neural plate, these data indicate that pinhead is a novel gene involved in controlling head development.
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Affiliation(s)
- Sue Kenwrick
- Cambridge Institute for Medical Research, Hills Road, Cambridge United Kingdom
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Liu Z, Zhang S, Liu M, Wang Y, Chu J, Xu A. Evolution and expression of the amphioxus AmphiHMGB gene encoding an HMG-box protein. Comp Biochem Physiol B Biochem Mol Biol 2004; 137:131-8. [PMID: 14698919 DOI: 10.1016/j.cbpc.2003.10.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Amphioxus HMGB gene, AmphiHMGB, encoding a high mobility group (HMG) protein was identified from the gut cDNA library of Branchiostoma belcheri tsingtauense. Primary structural examination indicates that it is a member of HMGB family. Molecular phylogenetic analysis suggests that AmphiHMGB represents the archetype of chordate HMGB genes including HMGB1, HMGB2 and HMGB3 although it may have lost its C-terminal domain during evolution. Northern blotting revealed that AmphiHMGB expression was restricted mainly to guts in the adult, and AmphiHMGB transcripts were in greater abundance in gastrula and neurula though they were markedly low in 1-day larva.
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Affiliation(s)
- Zhenhui Liu
- Department of Marine Biology, Ocean University of China, Qingdao 266003, PR China
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Lee KB, Thomas JO. The effect of the acidic tail on the DNA-binding properties of the HMG1,2 class of proteins: insights from tail switching and tail removal. J Mol Biol 2000; 304:135-49. [PMID: 11080451 DOI: 10.1006/jmbi.2000.4206] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The high-mobility group (HMG) proteins HMG1, HMG2 and HMG2a are relatively abundant vertebrate DNA-binding and bending proteins that bind with structure specificity, rather than sequence specificity, and appear to play an architectural role in the assembly of nucleoprotein complexes. They have two homologous "HMG-box" DNA-binding domains (which show about 80 % homology) connected by a short basic linker to an acidic carboxy-terminal tail that differs in length between HMG1 and 2. To gain insights into the role of the acidic tail, we examined the DNA-binding properties of HMG1, HMG2b and HMG2a from chicken erythrocytes (corresponding to HMG1, HMG2 and HMG2a in other vertebrates). HMG1, with the longest acidic tail, is less effective than HMG2a and 2b (at a given molar input ratio) in supercoiling relaxed, closed circular DNA, in inducing ligase-mediated circularisation of an 88 bp DNA fragment, and in binding to four-way DNA junctions in a gel-shift assay. Removal of the acidic tail increases the affinity of the HMG boxes for DNA and largely abolishes the differences between the three species. Switching the acidic tail of HMG1 for that of HMG2a or 2b gives hybrid proteins with essentially the same DNA-binding properties as HMG2a, 2b. The length (and possibly sequence) of the acidic tail thus appears to be the dominant factor in mediating the differences in properties between HMG1, 2a and 2b and finely tunes the rather similar DNA-binding properties of the tandem HMG boxes, presumably to fulfill different cellular roles. The tail is essential for structure-selective DNA-binding of the HMG boxes to DNA minicircles in the presence of equimolar linear DNA, and has little effect on the affinity for this already highly distorted DNA ligand, in contrast to binding to linear and four-way junction DNA.
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Affiliation(s)
- K B Lee
- Cambridge Centre for Molecular Recognition and Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, UK
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Lum HK, Lee KD, Yu G. The chicken genome contains no HMG1 retropseudogenes but a functional HMG1 gene with long introns. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1493:64-72. [PMID: 10978508 DOI: 10.1016/s0167-4781(00)00164-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We have cloned the genomic sequence coding for the high mobility group 1 (HMG1) protein in chickens. Multiple sequence alignment shows that the chicken HMG1 gene is highly homologous to the human and the mouse HMG1 genes. The gene structure of chicken HMG1 is similar to that of the mouse and the human HMG1 genes, with the same exon-intron boundaries. However, in contrast to other avian genes that have shorter introns, the chicken HMG1 gene has introns that are twice as long as their mammalian homologues. In addition to the functional, intron-containing HMG1 gene, all mammalian genomes contain more than 50 copies of HMG1 retropseudogenes each, while in the chicken genome there are no HMG1 retropseudogenes. This finding suggests that the HMG1 retropseudogenes arose in mammals after their divergence away from the birds.
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Affiliation(s)
- H K Lum
- Department of Applied Biology and Chemical, Technology, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
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Lee KB, Brooks DJ, Thomas JO. Selection of a cDNA clone for chicken high-mobility-group 1 (HMG1) protein through its unusually conserved 3'-untranslated region, and improved expression of recombinant HMG1 in Escherichia coli. Gene 1998; 225:97-105. [PMID: 9931456 DOI: 10.1016/s0378-1119(98)00542-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Screening of cDNA libraries for the homologous vertebrate proteins high mobility group (HMG) 1 and 2 using DNA probes based on the coding sequences is likely to result in isolation of both HMG1 and HMG2 clones, as well as pseudogenes, which may be transcribed at low levels. However, the 3'-untranslated regions (UTRs) of HMG1 and 2 are quite distinct, and unusually conserved across species. We have used this property to select the true chicken HMG1 cDNA clone from a chicken lymphocyte cDNA library in lambdagt11, using a probe based on the 3'-UTR of rat HMG1 cDNA. The chicken HMG1 cDNA clone is very similar to all the complete HMG1 cDNA clones isolated so far. We suggest that the sequence designated chicken HMG1 in the GenBank Data Library (Accession number D14314) is, in fact, that of HMG2a [and moreover that the recently reported mouse clone (Accession number AF022465), proposed to encode a new HMG protein, HMG4, is also likely to encode an HMG2a, based on the translated amino-acid sequence and 3'-UTR]. We also report much improved expression of intact recombinant HMG1 in Escherichia coli by the use of chloramphenicol rather than ampicillin selection and conditions that limit cell growth. This should be general for all members of the HMG1 (and 2) family which may be toxic to cells (possibly because of the long acidic tail), and may also prove useful in the production of other such proteins.
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Affiliation(s)
- K B Lee
- Cambridge Centre for Molecular Recognition and Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK
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