High impact information on Pxd

• Defects were found in the median part of the central nervous system in whole-mount embryos stained with anti-HRP (horseradish peroxidase) antibodies [1].
• Each 1512 residue chain of the three-armed, disulfide-linked homotrimer combines a peroxidase domain with six leucine-rich regions, four Ig loops, a thrombospondin/procollagen homology and an amphipathic alpha-helix [2].
• We have previously reported a sensitive immunochemical method for detecting 5-methylcytosine in DNA which involves spotting DNA samples on nitrocellulose paper and detection of 5-methylcytosine, if any, by a combination of the double antibody method and a staining reaction brought about by biotin-avidin and peroxidase [3].
• Antibodies specific for horseradish peroxidase (HRPeroxase) bind to neuronal membranes in Drosophila and serve as a specific neuronal marker [4].
• The site of hybridization is then detected either fluorimetrically, by using fluorescein-labeled goat anti-rabbit IgG, or cytochemically, by using an anti-rabbit IgG antibody conjugated to horseradish peroxidase [5].

Biological context of Pxd

• The in situ hybridization clearly shows that the Pxd mRNA is specifically expressed in follicle cells during the late stages of oogenesis 11-14, while the reverse transcription reactions dictate the stage-specific developmental regulation of the Pxd gene [6].
• The gene (DmPO) appears as a single copy gene located on the third chromosome at position 89 D/E [7].
• Comparative sequence analysis disclosed that the bPxd cDNA semi-central region, which encodes for the putative catalytic domain of the enzyme, exhibits great homology (98%) with its Pxd counterpart [8].
• Our conclusions are based on combined analysis of reporter expression from P[GAL4] driver lines, horseradish peroxidase injections into blastoderm stage embryos, cell labeling via heat-shock-induced flip-out in the embryo, bromodeoxyuridine birth dating and staining for programmed cell death [9].
• Neural pathways in invertebrates are often tracked using anti-horseradish peroxidase, a cross-reaction due to the presence of core alpha1,3-fucosylated N-glycans [10].

Anatomical context of Pxd

• The immunolocalization approach, using the anti-rAePO polyclonal antibody, has revealed that the Pxd peroxidase is selectively localized in the chorion structures and particularly in the endochorion and innermost chorionic layer (ICL) [6].
• Immunoelectron microscopy with peroxidase-labeled second antibody demonstrates that the varicosities are surrounded by a subsynaptic reticulum, that they contain immunoreactive vesicles of about 30-50 nm, and thus probably represent synaptic release sites [11].
• As shown by mass spectrometric and chromatographic analyses, only the BG2-c6 cell line expresses alpha1,3/alpha1,6-difucosylated N-glycans, a result that correlates with anti-horseradish peroxidase binding [10].
• Genetic dissection of endocytic trafficking in Drosophila using a horseradish peroxidase-bride of sevenless chimera: hook is required for normal maturation of multivesicular endosomes [12].
• The cells in these cultures had the properties of neurons of the Drosophila CNS: They gave rise to ganglion-like clusters from which neurites extended on the culture substrate, and they expressed the enzyme, acetylcholinesterase, and the cell surface antigens recognized by antisera raised against horseradish peroxidase [13].

Associations of Pxd with chemical compounds

• Moreover, the mature form of the Pxd recombinant protein was specifically recognized by the anti-rAePO antibody as a 77 kDa band, while in the presence of H2O2 was able to convert tyrosine residues to di-tyrosine moieties [6].
• Refeeding, topical application of juvenile hormone analogue to starved females or hormone addition to the culture medium, all caused the yolk spheres to become labelled with OZI and to incorporate peroxidase [14].
• For many years, polyclonal antibodies raised against the plant glycoprotein horseradish peroxidase have been used to specifically stain the neural and male reproductive tissue of Drosophila melanogaster [15].
• Both GST D1 and GST D21 have similar levels of GSH peroxidase activity against cumene hydroperoxide [16].
• Here we report that N-glycan core alpha1,3-linked fucose is, as judged by preabsorption experiments, indispensable for recognition of Drosophila embryonic nervous system by anti-horseradish peroxidase antibody [15].

Regulatory relationships of Pxd

• The removal of both maternal and zygotic Mgat1 also gave rise to embryos that no longer express the horseradish peroxidase antigen within the central nervous system [17].

Other interactions of Pxd

• Furthermore, only transfection of FucTA cDNA into S2 cells resulted in expression of the anti-horseradish peroxidase epitope, a result compatible with its substrate specificity in vitro [10].
• Using Green Fluorescent Protein (GFP) and horseradish peroxidase fusion proteins we show that Smo accumulates in the plasma membrane of cells in which Ptc activity is abrogated by Hh but is targeted to the degradative pathway in cells where Ptc is active [18].
• The GST D27 has both conjugation activity against the common substrate 1-chloro-2,4-dinitrobenzene and peroxidase activity against cumene hydroperoxide [19].
• Using anti-horseradish peroxidase staining, we show that the formation of the embryonic brain requires tll [20].
• Such single-stranded DNA protein complexes have been tested for blot hybridization using two colorimetrically detectable enzymes, namely peroxidase and alkaline phosphatase, as the protein moiety of the probe [21].

Analytical, diagnostic and therapeutic context of Pxd

• Northern blotting analysis of total RNA preparations revealed distinct molecular weight patterns of the Pxd RNA transcripts among adult flies, ovaries and larvae [6].
• The neuron innervating the antero-notopleural bristle was filled with horseradish peroxidase and studied at the light- and electron-microscopy level [22].
• Green fluorescent protein (GFP), expressed in a subset of sensory neurons from a selected enhancer trap line, is visualized by conventional immunohistochemistry with a peroxidase-linked antibody, and neural architecture is revealed by reduced silver staining [23].

References