Disease relevance of Gal

• Such an analysis is of particular interest because Drosophila is commonly used for making transformants that carry fusion genes in which the E. coli beta-galactosidase gene, lacZ, is used as a reporter gene [1].
• Severe hypoxia blocked expression of a heat-shock-inducible lacZ transgene [2].
• A HES-1 and lacZ-transducing retrovirus (SG-HES1) and a control lacZ-transducing retrovirus (SG) were injected into the lateral ventricles of mouse embryos, and the fate of the infected neural precursor cells was examined by X-gal staining [3].
• The development of the lamina, the first optic ganglion of the fly visual system, depends on inductive cues from the innervating photoreceptor axons. lacZ expression from a P-element insertion, A72, occurs in the anlage of the lamina coincident with axon ingrowth from the eye imaginal disc [4].
• For type B, a variation of enhancer detection was devised in which beta-galactosidase is assayed spectrophotometrically with and without bacterial infection [5].

High impact information on Gal

• We screened 11,000 enhancer trap lines, isolated several expressing beta-galactosidase in small subsets of muscle fibers prior to innervation, and identified two of these as inserts in connectin and Toll, members of the leucine-rich repeat gene family [6].
• In the ectoderm, all galactosidase-positive transformants show the same characteristic pattern [7].
• To investigate the in vivo function of Cutl1, we have replaced the C-terminal Cut repeat 3 and homeodomain exons with an in-frame lacZ gene by targeted mutagenesis in the mouse [8].
• A 1.2-kb Fab-7 DNA fragment was placed between divergently transcribed white and lacZ test promoters and challenged with several defined enhancers expressed in the early embryo [9].
• Here, we describe the exact replacement of a defective unmarked P element by an enhancer-trap transposon marked by the miniwhite gene and carrying lacZ as a reporter gene [10].

Chemical compound and disease context of Gal

• We characterized 120 novel yeast Ga14-targeted enhancer trap lines in Drosophila using upstream activating sequence (UAS) reporter plasmids incorporating newly constructed fusions of Aequorea victoria green fluorescent protein (GFP) and Escherichia coli beta-galactosidase genes [11].

Biological context of Gal

• The results of an EMS mutagenesis screen showed that, besides the beta-Gal-1 locus, there are four loci defined by recessive lethal mutations which map in the 26A7-9 region [12].
• In the first, gene dosage dependent variation in beta-galactosidase activity levels in segmental aneuploids, generated from crosses of Y-autosome translocation stocks, was determined quantitatively [12].
• Endogenous beta-galactosidase activity in the larval, pupal, and adult stages of the fruit fly, Drosophila melanogaster, indicates need for caution in lacZ fusion-gene studies [1].
• The lines were analyzed in two ways: (1) the identification of cis-acting patterning information within the Drosophila genome, as revealed by a lacZ reporter gene within the P element, and (2) the isolation of lethal mutations [13].
• Mutated Pc proteins were expressed as Pc-beta-galactosidase fusion proteins, and their nuclear distribution was examined by indirect immunofluorescence in tissue culture cells and on polytene chromosomes of transgenic larvae [14].

Anatomical context of Gal

• In the course of testing this compound, a new beta-galactoside hydrolytic activity, different from the previously identified beta-galactosidase, has been discovered to reside in macrophages and the intervitelline space [15].
• Thereafter, beta-galactosidase activity is undetectable until the pupal stage when the prothoracic gland-corpora allata and the optic lobes are beta-galactosidase positive [16].
• We show that 14 kb of 5'-flanking DNA directs expression of seven lacZ stripes in the blastoderm embryo [17].
• Nearly ubiquitous expression of the zeste-lacZ gene is found in late embryos and first instar larvae, but disappears almost completely except in brain and gonads by third instar larva [18].
• We have used lacZ reporter gene constructs to study the promoter/enhancer regions of the Drosophila FMRFamide neuropeptide gene in germ line transformants [19].

Associations of Gal with chemical compounds

• The position of the alpha-glycerophosphate dehydrogenase (alpha-Gpdh) gene in 26A5-7 has been confirmed and a putative transcriptional unit for the beta-galactosidase-1 (beta-Gal-1) gene has been identified in the 26A7-9 interval [20].
• Novel, highly fucosylated truncated structures are also present which are difucosylated on the proximal N-acetylglucosamine of the chitobiose core as well as containing unusual Fuc alpha 1-2 Gal 1-2 Man as peripheral structures [21].
• The major acidic lipid, designated Az29, possesses two PEtn moieties and a glucuronic acid linked to a Gal-extended Nz28 [22].
• The regulation of the Drosophila melanogaster hsp23 gene by heat shock and ecdysterone has been analysed by measuring activities of hsp--Escherichia coli beta-galactosidase hybrid genes in transfected hormone-sensitive D. melanogaster cells [23].
• We found that expression of beta-galactosidase can be efficiently inhibited in embryos and larvae with tetracycline provided in the food, and that a simple removal of the larvae from tetracycline exposure results in the induction of the enzyme in a time- and concentration-dependent manner [24].

Physical interactions of Gal

• The Deformed binding site is essential for temporal and spatial expression of beta-galactosidase during embryogenesis but is not required in the adult [25].

Regulatory relationships of Gal

• We identified cis-acting Kr control units which drive beta-galactosidase expression in 10 known locations of Kr expression in early and late embryos [26].

Other interactions of Gal

• Strikingly, DmGlcAT-I has specificity for Galbeta1-3Galbeta1-4Xyl, whereas DmGlcAT-BSI and DmGlcAT-BSII act on a wide array of substrates with non-reducing terminal beta1,3- and beta1,4-linked Gal residues [27].
• If a pulse of Gal-Pc is provided, synthetic reporter genes are repressed, though only transiently [28].
• Antibodies raised against a beta-galactosidase-K10 fusion protein were used to visualize the K10 product in ovaries by indirect immunofluorescence [29].
• Deletion mutants of the putative 5' promoter regions of Est-6 were fused to the bacterial beta-galactosidase gene (lacZ) and assayed for their ability to direct tissue-specific expression in transformed D. melanogaster adults [30].
• We compared the pattern of in vivo chromosomal binding of deleted forms of the sry delta protein fused to beta-galactosidase and expressed in Drosophila transgenic lines [31].

Analytical, diagnostic and therapeutic context of Gal

• We have constructed such maps by applying X-gal staining methods to serial frozen sections and whole mounts of larval, prepupal, pupal, and adult stages of D. melanogaster reared under axenic conditions [1].
• The temporal and spatial expression of the period gene of Drosophila melanogaster has been analyzed by examining the expression of a per beta-galactosidase fusion gene in transformants and by in situ hybridization experiments with wild-type flies [16].
• Polyclonal sera directed against the bacterial lacZ fusion protein recognized the same nuclear protein on Western blots [32].
• By immunoprecipitation, we showed that two of the largest subunits of RNA pol II coprecipitated with the N-terminal 315-residue fusion protein by using antibodies against beta-galactosidase [33].
• Additionally, we have initiated a dissection of pb's promoter and enhancer elements using lacZ reporter gene constructs [34].

References