Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.2.8 (hypoxanthine-guanine phosphoribosyltransferase)
 2,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to combine a cloned genomic copy of a selectable gene with different cloned centromeric sequences to develop mammalian artificial chromosomes (MAC) we used site specific recombination mediated by purified Cre recombinase acting on the loxP sequence in PAC vector DNA. A new method was required to purify highly concentrated, virtually 100% intact PAC DNA which could be stored for a long period. Here we show the efficient linking of linearized PACs containing alpha satellite DNA from chromosomes X and 17 with sizes of 125 and 140 kb, respectively, to a 95 kb restriction fragment derived from a 175 kb PAC containing the intact human HPRT gene locus.
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PMID:Efficient combination of large DNA in vitro: in gel site specific recombination (IGSSR) of PAC fragments containing alpha satellite DNA and the human HPRT gene locus. 915 31

We have investigated the potential of PAC-based vectors as a route to the incorporation of a gene in a mammalian artificial chromosome (MAC). Previously we demonstrated that a PAC (PAC7c5) containing alpha-satellite DNA generated mitotically stable MACs in human cells. To determine whether a functional HPRT gene could be assembled in a MAC, PAC7c5 was co-transfected with a second PAC containing a 140 kb human HPRT gene into HPRT-deficient HT1080 cells. Lines were isolated containing a MAC hybridizing with both alpha-satellite and HPRT probes. The MACs segregated efficiently, associated with kinetochore proteins and stably expressed HPRT message after 60 days without selection. Complementation of the parental HPRT deficiency was confirmed phenotypically by growth on HAT selection. These results suggest that MACs could be further developed for delivering a range of genomic copies of genes into cells and that stable transgene expression can be achieved.
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PMID:Stable gene expression from a mammalian artificial chromosome. 1157 Dec 65

Human artificial chromosomes (HACs) can be formed de novo by transfection of large fragments of cloned alphoid DNA into human HT1080 cells in tissue culture. In order to generate HACs carrying a gene of interest, one can either co-transfect the alphoid DNA and the gene of interest, or one can clone both into a single vector prior to transfection. Here we describe linking approximately 70 kb of alphoid DNA onto a 156-kb BAC carrying the human HPRT gene using Red homologous recombination in the EL350 Escherichia coli host [Lee et al., Genomics 73 (2001) 56-65]. A selectable marker and EGFP marker were then added by loxP/Cre recombination using the arabinose inducible cre gene in the EL350 bacteria. The final construct generates minichromosomes in HT1080 cells and the HPRT gene is expressed. The retrofitting vector can be used to add the approximately 70 kb of alphoid DNA to any BAC carrying a gene of interest to generate a HAC vector. The method can also be used to link any unrelated BAC or PAC insert onto another BAC clone. The EL350 bacteria are an excellent host for building up complex vectors by a combination of homologous and loxP/Cre recombination.
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PMID:Construction of human artificial chromosome vectors by recombineering. 1583 32

RHOXF1 has been shown to be expressed in embryonic stem cells, adult germline stem cells and some cancer lines. It has been proposed as a candidate gene to encode transcription factors regulating downstream genes in the human testis with antiapoptotic effects. Its expression in cancer cell lines has implied a similar role in the process of tumorigenesis. The human breast cancer cell lines MDA-MB-231 and MCF-7 were cultured in DMEM medium and transfected with a pGFP-V-RS plasmid bearing an RHOXF1 specific shRNA. Quantitative real- time RT-PCR was performed for RHOXF1, CASP8, BCL2 and HPRT genes. Decreased RHOXF1 expression was confirmed in cells after transfection. shRNA knock down of RHOXF1 resulted in significantly decreased BCL2 expression in both cell lines but no change in CASP8 expression. shRNA targeting RHOXF1 was shown to specifically mediate RHOXF1 gene silencing, so RHOXF1 can mediate transcriptional activation of the BCL2 in cancers and may render tumor cells resistant to apoptotic cell death induced by anticancer therapy. shRNA mediated knock down of RHOXF1 can be effective in induction of apoptotic pathway in cancer cells via BCL2 downregulation, so it can have potential therapeutic utility for human breast cancer.
Asian Pac J Cancer Prev 2012
PMID:shRNA mediated RHOXF1 silencing influences expression of BCL2 but not CASP8 in MCF-7 and MDA-MB-231 cell lines. 2331 70