rev: May 26, 2005
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(anti-Human and others as indicated)
RDI Divison of researchd Industries Intl offers a wide line of antibodies. Since no one antibody works best for all applications (neutralization, blotting, ELISA, etc), we offer many different types of antibodies to help solve this problem. Please inquire for other applications or types of antibodies not listed below.
Fibrillarin/Nop1p Monoclonal Antibody
Catalog Number: RDI-ALS24502 $344.00/100ul
Description: Nop1p was originally identified as a nucleolar protein of bakers yeast, Saccharomyces cerevisiae The Nop1p protein is 35 kDa, is essential for yeast viability, and is localized in the nucleoli (1). Nop1p is the yeast homologue of a protein apparently found in all eukaryotes and archea generally called fibrillarin. Fibrillarin/Nop1p is extraordinarily conserved, so that the yeast and human proteins are 67% identical, and the human protein can functionally replace the yeast protein. This means that suitably cross-reactive antibodies to Nop1p/fibrillarin, like MCA-38F3, can be used to reveal nucleoli and study fibrillarin/Nop1p in all eukaryotes and archea tested to date. Patients with the autoimmune disease scleroderma often have strong circulating autoantibodies to a ~34kDa protein which was subsequently found to be fibrillarin. Recent studies show that knock out of the fibrillarin gene in mice results in embryonic lethality, although mice with only one functional fibrillarin/Nop1p gene were viable (3). This antibody is becoming widely used as a convenient marker for nucleoli in a wide variety of species (e.g. 4).
Host Species: Mouse
Specificity: Mice were injected with yeast nuclear preparations and hybridomas were screened by immunofluorescence on yeast cells and by western blotting on yeast protein homogenates. Reference 2 below describes the characterization of D77, an antibody very similar but not identical to 38F3. This clone was selected because it stains a single ~34kDa band on western blotting and shows a clear and strong punctate staining of yeast nuclei. Subsequently it was found that this antibody recognizes fibrillarin in a wide variety of species including human, rat, Drosophila, S. pombe, C. elegans, and plants. It can therefore be used to identify nucleoli immunocytochemically.
Applications: For western blots of yeast protein samples, use 38F3 diluted 1/2,000 (cell lysates) to 1/10,000 (nuclear fractions), followed by chemiluminescent detection (ECL). For other (non-ECL) western detection methods, try 38F3 diluted 1/1,000 to 1/5,000. To detect mammalian fibrillarin on western blots by ECL, try 38F3 at 1/500 dilution. For immunofluorescence on yeast cells, use 38F3 diluted 1/1,000 to 1/5,000. For IF of mammalian cells, try 38F3 at 1/500. Antibody preparation contains 10mM sodium azide preservative
Format: Sterile cell culture fluid plus sodium azide. The immunoglobulin subtype is IgG1. The exact concentration of IgG is unknown.
Storage: Maintain at +2-8°C for 3 months or at -20°C for longer periods. Stable for 1 year. Avoid repeated freeze-thaw cycles.
1. Ochs RL, Lischwe MA, Spohn WH, Busch H. Fibrillarin: a new protein of the nucleolus identified by autoimmune sera. Biol Cell 54:123-133 (1985).
2. Aris JP and Blobel G. Identification and characterization of a yeast nucleolar protein that is similar to a rat liver nucleolar protein. J. Cell Biol. 107:17-31 (1988).
3. Newton K, Petfalski E, Tollervey D, Caceres JF. Fibrillarin is essential for early development and required for accumulation of an intron-encoded small nucleolar RNA in the mouse. Mol Cell Biol. 23:8519-8527 (2003).
4. Tyagi S and Alsmadi O. Imaging native beta-actin mRNA in motile fibroblasts. Biophys J. 87:4153-62
(Research Diagnostics Inc)
San Jose, 95123 CA Snell ave 658
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