1: Genetika. 2004 Jan;40(1):102-12. [Deletional polymorphism of the 11th intron of the human c-fms gene: allele frequency in certain Russian populations and possible functional significance] [Article in Russian] Kuznetsova TN, Voevoda MI, Podkolodnaia OA, Kulikov IV, Kobzev VF, Ustinov SN, Maliutina SK, Logvinenko NI, Zhuravskaia EIa, Cherdyntseva NV, Tumanov IuV, Morozova OA, Baum VA, Romashchenko AG. Institute of Cytology and Genetics, Russian Academy of Sciences, Novosibirsk, 630090 Russia. verzun@bionet.nsc.ru Analysis of deletion polymorphism of human c-fms gene intron 11 (approximately 425-bp deletion) is of particular interest because of the increased proportion of the deletion heterozygotes among the infants born from the parents, one of which lacks the deletion allele, and the other is heterozygous for the deletion. In this study, allele and haplotype frequencies of the polymorphism examined were assessed in a number of Caucasoid and Mongoloid populations of Russia. In all populations tested, relatively high prevalence of the deletion-bearing allele, ranging from 9.45% in ethnic Germans to 20.75% in Altaians, was detected. Russians and Kazakhs were characterized by intermediate frequencies of the rare allele, constituting in these populations 12.89 and 14.93%, respectively. Hardy-Weinberg expectations were met in all populations examined, pointing to a stable level of polymorphism at the c-fms intron 11. It was established by the context analysis of DNA of the deleted fragment along with the flanking sequences that this region contained a number of transcription factor motifs (Ets, SRF, and Myc), potentially capable of the regulation of the M-CFF-dependant c-fms transcription. The deletion breakpoint was localized within the CArG motif, which, together with the neighboring ets motif, form the potential CArG/ets composite element. It was suggested that allele lacking the fragment of intron 11 could be restricted in its ability to modulate the level of the c-fms transcription in response to the action of M-CSF. The data of molecular epidemiological survey serve as the indirect evidence favoring the suggestion on the possible functional value of this gene fragment. It was demonstrated that in the samples of acute bronchitis and trichomoniasis patients allelic and genotype frequencies were statistically significantly different from those in the population sample. In case of trichmoniasis, the frequency of rare allele was 2.4 times lower, and in case of acute bronchitis it was 2.1 times higher than in the control sample. PMID: 15027206 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 2: Cells Tissues Organs. 2003;174(1-2):63-72. Induction of early growth response gene Egr2 by basic calcium phosphate crystals through a calcium-dependent protein kinase C-independent p44/42 mitogen-activated protein kinase pathway. Zeng XR, Sun Y, Wenger L, Cheung HS. Department of Medicine, University of Miami School of Medicine, Miami, Fl 33101, USA. Using the reverse transcriptase-polymerase chain reaction we examined the effect of basic calcium phosphate (BCP) crystals on the induction of the early growth response gene Egr2 transcription and the signal transduction pathway involved. The results showed that BCP crystals induced Egr2 transcription up to 8-fold, peaking at 24 h after treatment. The induction of Egr2 was confirmed by transient transfection assays using an Egr2 promoter/luciferase reporter construct and could be inhibited by the p44/42 mitogen-activated protein kinase (MAPK)-specific inhibitor U0126, or by calcium chelator TMB-8, but not by the SAPK2/p38 MAPK inhibitor SB202190 or by the protein kinase C inhibitor bisindolylmaleimide I (Bis-I). Using the Mercury Pathway Profiling System (Clontech, Palo Alto, Calif., USA) we further showed that induced Egr2 could stimulate the activities of several transcription factors that are associated with cell proliferation, such as c-fos, SRF and c-myc. Copyright 2003 S. Karger AG, Basel PMID: 12784042 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 3: Dev Biol. 2001 Dec 15;240(2):531-47. Identification of a CArG box-dependent enhancer within the cysteine-rich protein 1 gene that directs expression in arterial but not venous or visceral smooth muscle cells. Lilly B, Olson EN, Beckerle MC. The Huntsman Cancer Institute and Department of Biology, University of Utah, Salt Lake City, Utah 84112, USA. brenda.lilly@hci.utah.edu Smooth muscle cells (SMCs) are heterogeneous with respect to their contractile, synthetic, and proliferative properties, though the regulatory factors responsible for their phenotypic diversity remain largely unknown. To further our understanding of smooth muscle gene regulation, we characterized the cis-regulatory elements of the murine cysteine-rich protein 1 gene (CRP1/Csrp1). CRP1 is expressed in all muscle cell types during embryogenesis and predominates in vascular and visceral SMCs in the adult. We identified a 5-kb enhancer within the CRP1 gene that is sufficient to drive expression in arterial but not venous or visceral SMCs in transgenic mice. This enhancer also exhibits region-specific activity in the outflow tract of the heart and the somites. Within the 5-kb CRP1 enhancer, we found a single CArG box that binds serum response factor (SRF), and by mutational analysis, demonstrate that the activity of the enhancer is dependent on this CArG element. Our findings provide further evidence for the existence of distinct regulatory programs within SMCs and suggest a role for SRF in the activation of the CRP1 gene. PMID: 11784081 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 4: Anticancer Drug Des. 1999 Jun;14(3):179-86. Effect of ecteinascidin-743 on the interaction between DNA binding proteins and DNA. Bonfanti M, La Valle E, Fernandez Sousa Faro JM, Faircloth G, Caretti G, Mantovani R, D'Incalci M. Department of Oncology, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy. Ecteinascidin-743 (ET-743) is a tetrahydroisoquinoline alkaloid isolated from Ecteinascidia turbinata, a tunicate growing in mangrove roots in Caribbean. It has been shown to bind in the minor groove of DNA forming covalent adducts by reaction of the N2 of guanine with the carbinolamine moiety. We investigated ET-743 ability to inhibit the binding of different transcription factors to their consensus sequences by using gel shift assays. We have selected three types of factors: (i) oncogene products such as MYC, c-MYB and Maf; (ii) transcriptional activators regulated during the cell cycle as E2F and SRF; and (iii) general transcription factors such as TATA binding protein (TBP), Sp1 and NF-Y. We observed no inhibition of the binding of Sp1, Maf, MYB and MYC. Inhibition of DNA binding was observed for TBP, E2F, SRF at ET-743 concentrations ranging from 50 to 300 microM. The inhibition of binding of NF-Y occurs at even lower concentrations (i.e. 10-30 microM) when the recombinant subunits of NF-Y are preincubated with the drug, indicating that the inhibition of NF-Y binding does not require previous ET-743 DNA binding. Since NF-Y is a trimer containing two subunits with high resemblance to histones H2B and H2A, we have investigated the effect of ET-743 on nucleosome reconstitution. ET-743 caused a decrease of the nucleosomal band at 100 nM, with the complete disappearance of the band at 3-10 microM. These data suggest that the mode of action of this novel anticancer drug is related to its ability to modify the interaction between some DNA binding proteins and DNA. PMID: 10500494 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 5: Exp Cell Res. 1996 Aug 1;226(2):372-80. Analysis of events associated with serum deprivation-induced apoptosis in C3H/Sol8 muscle satellite cells. Mampuru LJ, Chen SJ, Kalenik JL, Bradley ME, Lee TC. Department of Biochemistry, State University of New York at Buffalo 14214, USA. Satellite cells are the source of new muscle fibers in postnatal skeletal muscle growth and regeneration. Regulation of satellite cell survival is of fundamental importance in maintaining normal muscle function. Here we describe and characterize a tissue culture model of satellite cell apoptosis. Kinetic studies indicate that serum deprivation triggers a set of sequential events: early cell death, transient cell cycle traverse, and delayed cell death. The satellite cell death occurs by apoptosis based on the internucleosomal DNA laddering, in situ DNA end-labeling, and the requirements for de novo protein synthesis and extracellular calcium influx. The transient period of cell cycle progression (7-11 h after serum withdrawal) is accompanied by temporal induction of members of the immediate early gene family, such as c-myc, c-fos, and SRF, and appears to precede the delayed phase of cell death. Satellite cell apoptosis can be suppressed by several growth factors and by blocking the activity of calpain, a calcium-regulated protease. The late phase of apoptosis is marked by selective activation of ubiquitin-mediated protein conjugation and degradation. This study defines several control points where satellite cell apoptosis may be genetically or pharmacologically intervened. PMID: 8806441 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 6: J Biol Chem. 1995 Mar 3;270(9):4209-12. The RNA polymerase I transcription factor UBF is the product of a primary response gene. Glibetic M, Taylor L, Larson D, Hannan R, Sells B, Rothblum L. Department of Molecular Biology and Genetics, University of Guelph, Ontario, Canada. Transcription of the ribosomal RNA genes by RNA polymerase I is tightly coordinated with the rate of cell growth. The RNA polymerase I transcription factor, UBF, activates transcription by binding to elements within the promoter and enhancer elements within the intergenic spacer but is not required for basal transcription. To assess the role of UBF in modulating ribosomal DNA transcription, we studied its expression in NIH3T6 fibroblasts when transcription was repressed in response to serum starvation and stimulated following refeeding. Our results demonstrate a correlation between the amounts of UBF protein and the rates of ribosomal DNA transcription in quiescent and serum-stimulated cells. Nuclear run-on assays and Northern blot analyses demonstrated that the UBF gene was a primary response gene, exhibiting characteristics similar to those of c-myc and SRF. These results suggest that the regulation of transcription of the UBF gene by polymerase II represents a pathway by which cells modulate transcription by RNA polymerase I. PMID: 7876178 [PubMed - indexed for MEDLINE] ---------------------------------------------------------------