Common warts are close associated with HPVs infection. In this study, we amplified and sequenced the LCR fragment and E2 gene of HPV-2 that infected the patient of extensive common wart with cutaneous horns, and we constructed the recombinant CAT-reporter plasmids pBLCAT-LCR containing HPV-2 prototype or variant LCR and mammalian expression plasmids pcDNA3. 1-E2 containing prototype or variant E2 ORF individually. The promoter activities of HPV-2 variant and the transcriptional repression activities of the mutated E2 protein were evaluated by transient transfection into HeLa cells. The results showed that there were several mutations in LCR and E2 gene of HPV-2 variant. Compared with the prototype, the viral early promoter activity of variant was significantly increased uder the control of LCR. Compared with the wild type E2 protein, the transcriptional repression activities of the mutated E2 protein was abolished partially. We speculate herein that increased promoter activities and decreased repression effect of the mutated E2 protein are linked, at least partially, with the clinical phenotypes of the uncommon huge common wart.
DNA-Binding Proteins ; genetics ; physiology ; Humans ; Mutation ; Oncogene Proteins, Viral ; genetics ; physiology ; Papillomaviridae ; genetics ; Promoter Regions, Genetic ; Repressor Proteins ; physiology ; Warts ; virology

As an important telomere binding protein, TPP1 protects the ends of telomeres and maintains the stability and integrity of its structure and function by interacting with other five essential core proteins (POT1, TRF1, TRF2, TIN2, and RAP1) to form a complex called Shelterin. Recently, researchers have discovered that TPP1 participates in protection of telomeres and regulation of telomerase activity. The relationship between TPP1 and tumorigenesis, tumor progression and treatment has also been investigated. This paper reviews the latest findings of TPP1 regarding to its structure, function and interaction with other proteins involved in tumorigenesis.
Chromosomal Instability ; DNA Damage ; Humans ; Neoplasms ; genetics ; Telomere ; Telomere-Binding Proteins ; chemistry ; physiology

Bacterial Proteins ; genetics ; metabolism ; Biofilms ; DNA-Binding Proteins ; genetics ; metabolism ; Flagella ; genetics ; metabolism ; Gene Expression Regulation, Bacterial ; Transcription Factors ; genetics ; metabolism ; Vibrio parahaemolyticus ; cytology ; genetics ; growth & development ; physiology

Antigens, Neoplasm ; genetics ; metabolism ; Breast Neoplasms ; enzymology ; genetics ; metabolism ; DNA Topoisomerases, Type II ; genetics ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Female ; Gene Expression Regulation, Neoplastic ; physiology ; Humans

OBJECTIVETo investigate telomerase gene expression in precancerous mammary lesion, such as atypical ductal hyperplasia and breast cancer and to study the relationship between expression and malignant transformation.

METHODSExpression of human telomerase genes (hTR) and human reverse transcriptase gene (hTRT) in 76 cases of mammary tissue was evaluated using in situ hybridization and included 50 cases of mammary hyperplasia, 6 of which were benign hyperplasia, 9 were mild atypical hyperplasia, 12 were moderate atypical hyperplasia, 23 were severe atypical hyperplasia and 26 were mammary cancer.

RESULTSThe expressions of hTR and hTRT mRNA were much weaker or negative in benign hyperplasia (16.6%, 0), weak to mild moderate in atypical hyperplasia (22.2%, 11.1%, 33.3%, 25.0%), strong in severe atypical hyperplasia (60.9%, 52.1%), and significantly strong in mammary cancer (88.5%, 80.8%). The difference between mild-moderate atypical hyperplasia, invasive ductal carcinoma and severe atypical hyperplasia was significant (P < 0.05) and the difference between severe atypical hyperplasia and intraductal carcinoma was not significant (P > 0.05).

CONCLUSIONTelomerase genes (hTR and hTRT) expressions are related to the transformation of atypical hyperplasia. Activated telomerase may play a role in mammary cancer development.

Breast ; metabolism ; pathology ; Breast Neoplasms ; genetics ; pathology ; DNA-Binding Proteins ; Female ; Gene Expression ; Humans ; Precancerous Conditions ; genetics ; pathology ; RNA ; genetics ; physiology ; RNA, Messenger ; analysis ; Telomerase ; genetics ; physiology

OBJECTIVETo explore the protein factors that could interact with the testis-specific protein encoded by HSD-3.8 gene (GenBank Accession Number AF311312) related with female fertilization.

METHODSYeast two-hybrid system was used to screen the human ovary MATCHMAKER cDNA library with constructed "bait plasmid" containing the 0.7 kb fragment (HSD-0.7) of HSD-3.8. The interaction with the positive fragments using a series of truncated bait plasmids was investigated.

RESULTSOne positive gene fragment was obtained, which coded for 144 amino acids of the C-terminus of human G protein beta subunit 1. Truncated bait plasmids couldn't interact with the fish protein fragment in yeast.

CONCLUSIONSThe protein encoded by HSD-3.8 gene may function through G protein signal transduction pathway and the interaction depends on the integration of the bait protein.

Adenosine Triphosphate ; metabolism ; Adult ; Antigens, Surface ; DNA-Binding Proteins ; genetics ; Female ; GTP-Binding Proteins ; genetics ; physiology ; Gene Library ; Humans ; Male ; Protein Biosynthesis ; Proteins ; genetics ; Spermatozoa ; chemistry ; physiology ; Synaptophysin ; Testis ; chemistry ; Two-Hybrid System Techniques ; Yeasts ; genetics

OBJECTIVETo synthesize highly pure HBV post-transcriptional regulatory element (HPRE) via transcription in vitro by T7 RNA polymerase.

METHODSHPRE gene was amplified by PCR from a template containing HBV complete genomic DNA and cloned into plasmid pGEM-11zf. The cloned DNA sequence was transcribed by T7 RNA polymerase.

RESULTSThe construction of HPRE gene recombinant plasmid and production of HPRE via transcription in vitro was successful.

CONCLUSIONIn vitro transcription by T7 RNA polymerase can be used to synthesize highly pure HPRE.

DNA-Directed DNA Polymerase ; DNA-Directed RNA Polymerases ; Hepatitis B virus ; genetics ; RNA Processing, Post-Transcriptional ; RNA Splicing ; RNA-Binding Proteins ; physiology ; Transcription, Genetic ; Viral Proteins

MRE11 plays an important role in the signal transduction of DNA damage response, therefore this study was purposed to explore the relationship between hMRE11 focus formation and DNA double-strand breaks (DSBs) caused by etoposide (VP-16) in human promonocytic cells U937. After U937 cells were treated with VP-16, the drug-induced DSBs were assessed by pulsed-field gel electrophoresis (PFGE), the gene transcription levels of hMRE11 were evaluated by RT-PCR, the nuclear focus formation of hMRE11 protein was examined using immunofluorescence technique, the cell cycle in parallel was analyzed by flow cytometry. The results showed that the percentage of U937 cells with DSBs induced by VP-16 raised from 13.0 +/- 2.3% in VP-16 2 microg/ml to 32.0 +/- 4.3% in VP-16 20 microg/ml (P < 0.01) along with increase of VP-16 dose. No difference of the hMRE11 mRNA level in U937 cells following the treatment with 100 microg/ml VP-16 at different times was discovered (P > 0.05). The hMRE11 protein was abundantly and uniformly distributed in the nuclei of untreated U937 cells outside of nucleoli, however, it formed discrete nuclear foci following VP-16 treatment. The mean value of nuclear foci increased by 5 to 20 times following the drug dosing (P < 0.01). An average of 5 nuclear foci per positive nucleus were observed at a dose of 2 microg/ml, and it was increased to an average of over 14 nuclear foci per positive nucleus after treating with VP-16 20 microg/ml. The percentage of nuclei containing hMRE11 nuclear foci also increased from less than 10% after treatment wiht VP-16 2 microg/ml to over 50% after VP-16 20 microg/ml (P < 0.01) following treatment with VP-16. After U937 cells were treated with 100 microg/ml VP-16 for 2 hours and fixed at 4, 8, 12 and 24 hours, the percentage of nuclei with hMRE11 nuclear foci increased to 61.54 +/- 3.6% (the control U937 cells: 0.47 +/- 1.17%, P < 0.01) at 8 hours, with a subsequent decrease in the percentage of nuclear foci-positive cells by 24 hours. The ratio of S-phase U937 cells at 8 hours after being treated with 100 microg/ml VP-16 for 2 hours was 47.55 +/- 2.35%, and that without 100 microg/ml VP-16 was 21.95 +/- 2.91% (P < 0.05). It is concluded that the nuclear focus formation of hMRE11 protein may be a response to DNA damage induced by topoisomerase II inhibitor VP-16 in human promonocytic cell line U937.
Antineoplastic Agents, Phytogenic ; pharmacology ; DNA Damage ; DNA Repair ; genetics ; physiology ; DNA-Binding Proteins ; biosynthesis ; genetics ; metabolism ; physiology ; Dose-Response Relationship, Drug ; Etoposide ; pharmacology ; Humans ; MRE11 Homologue Protein ; Protein Binding ; RNA, Messenger ; biosynthesis ; genetics ; Signal Transduction ; Topoisomerase II Inhibitors ; U937 Cells

The low dose hyper-radiosensitivity (HRS) in human lung cancer cell line A549 was investigated, the changes of ATM kinase, cell cycle and apoptosis of cells at different doses of radiation were observed, and the possible mechanisms were discussed. A549 cells in logarithmic growth phase were irradiated with (60)Co gamma-rays at doses of 0-2 Gy. Together with flow cytometry for precise cell sorting, cell survival fraction was measured by means of conventional colony-formation assay. The expression of ATM1981Ser-P protein was examined by Western blot 1 h after radiation. Apoptosis was detected by Hoechst 33258 fluorescent staining, and Annexin V-FITC/PI staining flow cytometry 24 h after radiation. Cell cycle distribution was observed by flow cytometry 6, 12 and 24 h after radiation. The results showed that the expression of ATM1981Ser-P protein was observed at 0.2 Gy, followed by an increase at >0.2 Gy, and reached the peak at 0.5 Gy, with little further increase as the dose exceeded 0.5 Gy. Twenty-four h after radiation, partial cells presented the characteristic morphological changes of apoptosis, and the cell apoptosis curve was coincident with the survival curve. As compared with control group, the cell cycle almost had no changes after exposure to 0.1 and 0.2 Gy radiation (P>0.05). After exposure to 0.3, 0.4 and 0.5 Gy radiation, G(2)/M phase arrest occurred 6 and 12 h after radiation (P<0.05), and the ratio of G(2)/M phase cells was decreased 24 h after radiation (P<0.05). It was concluded that A549 cells displayed the phenomenon of HRS/IRR. The mode of cell death was mainly apoptosis. The activity of ATM and cell cycle change may take an important role in HRS/IRR.
Cell Cycle Proteins/genetics ; Cell Cycle Proteins/metabolism ; Cell Cycle Proteins/physiology ; Cell Line, Tumor ; DNA-Binding Proteins/antagonists & inhibitors ; DNA-Binding Proteins/metabolism ; DNA-Binding Proteins/*physiology ; Dose-Response Relationship, Radiation ; Lung Neoplasms/*pathology ; Protein-Serine-Threonine Kinases/*metabolism ; Radiation Dosage ; Radiation Tolerance/*physiology ; Tumor Suppressor Proteins/metabolism

In this new era of the genome, the complete sequences of various organisms (from the simplest to the most complex such as human) are now available, which provides new opportunities to study biology and to develop therapeutic strategies. But the paucity of research tools that manipulate specific genes in vivo represents a major limitation of functional genomic studies. In nature, the expression of genes is regulated at the transcriptional level primarily by proteins that bind to nucleic acids. Many of these proteins, which are termed transcription factors, are typically consist of two essential yet separable modules: DNA-binding domain (DBD) and effector domain (ED). Attempts to control the gene expression by artificial transcription factors are based on the application of this rule. Among the many naturally occurring DNA-binding domains, the Cys2-His2 zinc-finger domain has demonstrated the greatest potential for the design of novel sequence-specific DNA-binding proteins. Each zinc finger domain, which comprises about 30 amino acids that adopt a compact structure by chelating a zinc ion, typically functions by binding 3 base pairs of DNA sequence. Several zinc fingers linked together would bind proportionally longer DNA sequences. Ideally, these artificial DNA binding proteins could be designed to specifically target and regulate one single gene within a genome as complex as that found in human. Such proteins would be powerful tools in basic and applied research.
DNA ; chemistry ; genetics ; metabolism ; DNA-Binding Proteins ; metabolism ; Gene Expression Regulation ; Humans ; Transcription Factors ; chemistry ; genetics ; metabolism ; Zinc Fingers ; genetics ; physiology