Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment of cultured neonatal ventricular myocytes with oncogenic Ras increases their size and stimulates the re-expression of genes which are normally restricted to the fetal stage of ventricular development, including atrial natriuretic factor (ANF) and skeletal muscle (SkM)-alpha-actin. To determine which signalling pathways mediate these responses, myocytes were transfected with oncogenic (V12) Ras mutants which interact selectively with different effectors and their effects on luciferase (LUX) reporter plasmids were examined. V12 human Ras (V12HRas), itself, activated ANF-LUX 9. 6-fold, whereas mutants of V12HRas, which selectively stimulate Ral guanine nucleotide dissociation stimulator (Ral.GDS) (E37G), c-Raf (D38E) and phosphatidylinositol 3-kinase (PI-3-K; Y40C) enhanced ANF-LUX expression 3.0-, 3.7- and 1.7-fold respectively. The full response of ANF-LUX to V12HRas was restored by using a combination of the individual effector domain mutants. Likewise, SkM-alpha-actin-LUX expression was activated 12.0-, 3.5-, 4.5- and 3. 0-fold by V12HRas, E37G, D38E and Y40C respectively, and a similar pattern of activation was also observed using a c-fos serum-response element-LUX reporter gene. Cell size was also increased by each of the mutants, but simultaneous expression of all three mutant constructs was needed to reconstitute the full effect of V12HRas on cell size (50% increase). Transfection with a constitutively active mutant of PI-3-K (p110K227E) stimulated ANF-LUX, SkM-alpha-actin-LUX, c-fos-serum-response element-LUX and Rous sarcoma virus-LUX by 3.1-, 3.2-, 2.1- and 2.9-fold respectively, but the co-transfected cytomegalovirus-beta-galactosidase reporter gene was activated to a similar extent (1.9-fold). These results suggest that Raf, Ral.GDS and PI-3-K can all transduce transcriptional responses to V12HRas, but that the specific induction of genes associated with the hypertrophic response is not mediated through PI-3-K.
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PMID:Stimulation of gene expression in neonatal rat ventricular myocytes by Ras is mediated by Ral guanine nucleotide dissociation stimulator (Ral.GDS) and phosphatidylinositol 3-kinase in addition to Raf. 976 20

Our research is directed towards enhancing the understanding of the molecular biology of dengue virus replication with the ultimate goal being to develop novel antiviral strategies based on preventing critical inter- or intra-molecular interactions required for the normal virus life cycle. The viral RNA-dependent RNA polymerase (NS5) and the viral helicase (NS3) interaction offers a possible target for inhibitors to bind and prevent replication. In this study the yeast-two hybrid system was used to show that a small region of NS5 interacts with NS3, and also with the cellular nuclear transport receptor importin-beta. Furthermore, intramolecular interaction between the two putative domains of NS5 can also be detected by the yeast two-hybrid assay. We have also modified the colony lift assay for the beta-galactosidase reporter activity in intact yeast cells which reflects the strength of interaction between two proteins to a microtiter plate format. This assay offers a unique opportunity to screen for small molecule compounds that block physiologically important interactions.
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PMID:Characterisation of inter- and intra-molecular interactions of the dengue virus RNA dependent RNA polymerase as potential drug targets. 1134 63

Dengue virus NS5 protein is a multifunctional RNA-dependent RNA polymerase that is essential for virus replication. We have shown previously that the 37- amino acid interdomain spacer sequence (residues (369)X(2)KKX(14)KKKX(11)RKX(3)405) of Dengue2 NS5 contains a functional nuclear localization signal (NLS). In this study, beta-galactosidase fusion proteins carrying point mutations of the positively charged residues or truncations of the interdomain linker region (residues 369-389 or residues 386-405) were analyzed for nuclear import and importin binding activities to show that the N-terminal part of the linker region (residues 369-389, a/bNLS) is critical for nuclear localization and is recognized with high affinity by the conventional NLS-binding importin alpha/beta heterodimeric nuclear import receptor. We also show that the importin beta-binding site (residues 320-368, bNLS) adjacent to the a/bNLS, previously identified by yeast two-hybrid analysis, is functional as an NLS, recognized with high affinity by importin beta, and able to target beta-galactosidase to the nucleus. Intriguingly, the bNLS is highly conserved among Dengue and related flaviviruses, implying a general role for the region and importin beta in the infectious cycle.
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PMID:The interdomain region of dengue NS5 protein that binds to the viral helicase NS3 contains independently functional importin beta 1 and importin alpha/beta-recognized nuclear localization signals. 1210 24

We have previously reported successful trans-complementation of defective Kunjin virus genomic RNAs with a range of large lethal deletions in the nonstructural genes NS1, NS3, and NS5 (A. A. Khromykh et al., J. Virol. 74:3253-3263, 2000). In this study we have mapped further the minimal region in the NS5 gene essential for efficient trans-complementation of genome-length RNAs in repBHK cells to the first 316 of the 905 codons. To allow amplification and easy detection of complemented defective RNAs with deletions apparently affecting virus assembly, we have developed a dual replicon complementation system. In this system defective replicon RNAs with a deletion(s) in the nonstructural genes also encoded the puromycin resistance gene (PAC gene) and the reporter gene for beta-galactosidase (beta-Gal). Complementation of these defective replicon RNAs in repBHK cells resulted in expression of PAC and beta-Gal which allowed establishment of cell lines stably producing replicating defective RNAs by selection with puromycin and comparison of replication efficiencies of complemented defective RNAs by beta-Gal assay. Using this system we demonstrated that deletions in the C-terminal 434 codons of NS3 (codons 178 to 611) were complemented for RNA replication, while any deletions in the first 178 codons were not. None of the genome-length RNAs containing deletions in NS3 shown to be complementable for RNA replication produced secreted defective viruses during complementation in repBHK cells. In contrast, structural proteins produced from these complemented defective RNAs were able to package helper replicon RNA. The results define minimal regions in the NS3 and NS5 genes essential for the formation of complementable replication complex and show a requirement of NS3 in cis for virus assembly.
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PMID:Complementation analysis of the flavivirus Kunjin NS3 and NS5 proteins defines the minimal regions essential for formation of a replication complex and shows a requirement of NS3 in cis for virus assembly. 1236 19

Due to the hypervariable character of hepatitis C virus (HCV), 5 conserved T and/or B cell epitopes from core, envelope, NS3 and NS5 protein of HCV were chosen to form a 270 bp multi-epitopes antigen gene. The gene was clone into a fusion vector pWR450-1 to express a beta-galactosidase-HCV hybrid protein GZ-PCX. The purified GZ-PCX protein was specifically recognized by human anti-HCV antibodies. These results show that the HCV hybrid multi-epitopes antigen has excellent immunogenicity, which might be able to be used as an effective diagnosis agent and to provide protectivity to any genotype of HCV which might partly solve the problems in the researches of HCV vaccines.
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PMID:[Expression of a HCV multi-epitopes antigen gene and study on its immunogenicity]. 1255 46