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J Thurlow

Publications and source records attributed to J Thurlow.

9 recordsLinked to original sources
PubMed2001

SOX6 binds CtBP2 to repress transcription from the Fgf-3 promoter.

Fgf-3 is expressed in a complex pattern during mouse development. Previously, an essential regulatory element PS4A was identified in the promoter region, and shown to bind at least three factors. To identify the transcription factor(s), we used a yeast one-hybrid screen and obtained a novel Sox6 cDNA (SOX6D). When introduced into cells it strongly repressed activity from both an Fgf-3 reporter gene as well as an artificial promoter containing three PS4A elements. In situ hybridisation analysis showed that Sox6 and Fgf-3 are co-expressed in the otic vesicle of E9.5 mouse embryos in a mutually exclusive pattern, consistent with a repression of Fgf-3 transcription by SOX6. To characterise additional factor(s) involved in Fgf-3 gene repression, a yeast two-hybrid screen was used with the N-terminal portion of SOX6D. Mouse CtBP2 cDNA clones were isolated and shown to bind SOX6 in yeast and mammalian cells. Furthermore, mutational analysis of SOX6 showed that binding to CtBP2, and its responsiveness to this co-repressor, were dependent on a short amino acid sequence motif PLNLSS. Co-expression studies in NIH3T3 cells showed that SOX6 and CtBP2 co-operate to repress activity from the Fgf-3 promoter through the enhancer element PS4A. These results show that SOX6 can recruit CtBP2 to repress transcription from the Fgf-3 promoter.

Alcohol Oxidoreductases↗
PubMed1999

Retinoic acid-regulated expression of fibroblast growth factor 3 requires the interaction between a novel transcription factor and GATA-4.

fgf-3 shows a complex spatial-temporal pattern of transcription during mouse development, and the gene product appears to be an important intercellular signaling molecule. Here we show that the major enhancer, which is obligatory for transcription, is composed of three elements with different properties. Both functional analyses in undifferentiated and differentiated F9 cells and characterization of DNA-protein complexes in vitro have identified the sequence motifs GTGACT(C), ATTGT, and GATA as the key transcription factor binding sites. The GTGACT(C) motif, while not essential, is required for full enhancer activity. However, binding at ATTGT is crucial for transcriptional activity and is required for cooperative binding at the proximal GATA site. The GATA binding site mediates the retinoic acid/dibutyryl cyclic AMP stimulation of transcription and correlates with the binding of Gata-4 which is induced by retinoic acid in differentiating F9 cells. The ATTGT and GATA motifs are inactive when placed separately on a minimal thymidine kinase (TK) promoter, but together they act as a strong retinoic acid-regulated enhancer. In undifferentiated F9 cells, gata-4 expression stimulates the fgf-3 promoter, whereas in differentiated F9 cells already expressing gata-4, no further increase in promoter activity was observed.

Animals↗
PubMed1998

Recovery characteristics using single-breath 8% sevoflurane or propofol for induction of anaesthesia in day-case arthroscopy patients.

We studied the induction and recovery characteristics following inhalational induction with 8% sevoflurane in nitrous oxide and oxygen compared with intravenous propofol in 40 patients presenting for arthroscopy of the knee. Patients were randomly allocated to receive either induction agent, and anaesthesia was then maintained with sevoflurane in oxygen and nitrous oxide. A computerised test of hand--eye co-ordination and a p-deletion test were used to measure psychomotor recovery. The sevoflurane group had a faster onset of anaesthesia time. No significant differences between the groups were found in time to eye opening or psychomotor tests. Nausea and vomiting scores were significantly higher at 30 min in the sevoflurane group (p = 0.04); this difference was no longer significant by 90 min. We conclude that inhalational induction with sevoflurane in these patients has no important clinical advantages and causes more nausea and vomiting than propofol.

Adolescent↗
PubMed1993

Identification of positive and negative regulatory elements involved in the retinoic acid/cAMP induction of Fgf-3 transcription in F9 cells.

The proto-oncogene Fgf-3 has been implicated as an important signalling molecule in vertebrate development. In the mouse, it is expressed for a limited time at a multitude of sites from embryonic day 7 to birth. Transcription of Fgf-3 initiates at three promoter regions resulting in the generation of various mRNAs which nevertheless all encode the same protein products. A 1.7kb DNA fragment which encompasses these regions was joined to the CAT reporter gene and shown to function as a promoter in embryonal carcinoma cells. In stable transfectants the promoter retains its retinoic acid inducibility, initiating transcription at the same cap-sites as the endogenous gene. In differentiated F9 cells, transient transfection of progressive and targeted deletion mutants of the promoter region has revealed at least two positive and three negative regulatory elements. With one exception, loss of these elements was shown to dramatically affect promoter activity in stable transfectants of F9 cells. However the promoter remained inducible by retinoic acid to differing degrees, apart from deletions encompassing PS-4A which essentially abolished promoter activity in both undifferentiated and differentiated cells. The sequences of these potential regulatory regions were further defined using DNase-I footprinting, revealing some similarities to consensus binding sites for known transcription factors.

Animals↗
PubMed1991

Transcriptional regulation of the int-2 gene in embryonal carcinoma cells.

The int-2 gene, which encodes a member of the fibroblast growth factor family, is expressed at specific sites and times during mouse development. In certain embryonal carcinoma cell lines, multiple int-2 transcripts accumulate when the cells are induced to differentiate with retinoic acid and dibutyryl cyclic AMP. Nuclear run-on analyses indicate that the apparent induction of int-2 expression results from an increase in the rate of transcription initiation. Six distinct types of RNA have been delineated, originating from three promoters and terminating at either of two polyadenylation sites. Since each transcript appears to encode the same protein, this complexity may reflect the need for lineage-specific or differentiation-dependent control of expression. By comparing the kinetics of induction and turnover of the different RNA species, we show that the choice of promoter or length of the 3'-untranslated region has no significant effect on the half-lives of the various mRNAs. To further evaluate control at the transcriptional level, we have shown that a 1.7-kilobase fragment of int-2 genomic DNA, when fused to the chloramphenicol acetyltransferase gene, can act as a regulated promoter(s) in differentiated versus undifferentiated embryonal carcinoma cells. This segment of DNA encompasses the three promoter regions previously delineated by RNase mapping plus about 900 base pairs of additional upstream sequences.

Animals↗
PubMed1989

The mouse homologue of hst/k-FGF: sequence, genome organization and location relative to int-2.

We have located and sequenced the murine homologue of the hst/k-FGF oncogene in genomic DNA clones that extend 3' from int-2 on mouse chromosome 7. The two genes are in the same transcriptional orientation, less than 20 kilobase pairs (kb) apart, and presumably evolved by tandem duplication of a common ancestral gene. RNase mapping and primer extension analyses indicated that the major 3.2 kb hst transcript expressed in undifferentiated embryonal carcinoma (EC) cell lines initiates at a unique cap site downstream from an obvious TATA-box. The 3' end of the transcript as identified in multiple cDNA clones occurs at an appropriate distance from a variant polyadenylation signal, ATTAAA. Translation of the major open reading frame would yield a 202 amino acid protein that is 82% homologous to human HST but lacking 4 residues at the presumed signal peptide cleavage site.

Amino Acid Sequence↗
PubMed1981

Current techniques of nutritional assessment.

This article has dealt with techniques of nutritional assessment as currently utilized in the hospital setting. Although the techniques are easily mastered and abundant data have been collected, we are only slightly closer to achieving an accurate and clinically meaningful nutritional assessment. Interpretation of data is hampered by reliance on tables of "norms" and by the questionable validity of relating individual tests to the whole patient. The interest stimulated in nutrition by widespread application of these assessment techniques, however, has resulted in a burst of new investigative efforts. Determination of body composition by total body neutron activation and isotope dilution during various states of nutrition, isotope studies of substrate utilization, and evaluation of body function relative to composition are all exciting areas of future investigation. Until an accurate comprehensive technique of nutritional assessment is available, emphasis must be placed on obtaining as much data as possible from the dietary and clinical history, physical examination, and anthropometric and laboratory measurements, with great reliance on clinical impression and judgement. At the current state of the art, in addition to the history and physical examination, we propose as a minimum that a nutritional assessment consist of current weight and recording of recent weight change, determination of serum albumin, transferrin, TLC, and testing for DTHR to common skin test antigens, and an evaluation of muscle function.

Anthropometry↗