rum1 Antibody
Description
Introduction
The rum1 Antibody is a research reagent used in molecular biology to detect and study the RRM1 protein (Ribonucleotide Reductase Large Subunit). This antibody is critical in understanding the role of RRM1 in DNA synthesis, cell cycle regulation, and disease mechanisms. Below is a detailed analysis of its characteristics, applications, and research findings.
Western Blotting (WB)
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Detects RRM1 in lysates from synchronized fission yeast cells, showing periodic expression during the G1 phase .
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Used to monitor RRM1 degradation via the ubiquitin-proteasome pathway in mts3-1 mutants .
Cell Cycle Regulation
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RRM1 interacts with p56cdc13 (mitotic cyclin) to promote its proteolysis during G1 arrest, ensuring proper cell cycle progression .
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Antibody-based studies show RRM1 levels oscillate inversely with p56cdc13 levels, peaking in G1 and declining in S/G2 phases .
Cancer Research
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RRM1 overexpression correlates with enhanced DNA synthesis and tumor growth, making it a potential therapeutic target .
Cell Cycle Dynamics
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In fission yeast, RRM1 binds p56cdc13 and p34cdc2 complexes, targeting them for degradation . This prevents premature entry into S-phase or mitosis .
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RRM1 degradation is mediated by the 26S proteasome, with ubiquitination confirmed via His6-ubiquitin conjugate assays .
Therapeutic Implications
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RRM1 inhibition reduces tumor growth in preclinical models by limiting nucleotide precursor availability .
Comparison of RRM1 vs. RUM-1 Antibodies
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- This research highlights a novel, positive mechanism responsible for Rum1's CKI activity. This mechanism involves the phosphorylation of Rum1 by the LAMMER kinase. PMID: 23376070
KEGG: spo:SPBC32F12.09
STRING: 4896.SPBC32F12.09.1
Q&A
Basic Research Questions
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What is RUM1 antibody and what is its primary application in research?
RUM1 is a human monoclonal IgM antibody with lambda light chain that targets the Rh D antigen (Rh1 or Rho), clinically the most important antigen of the Rh blood group system. It recognizes epitopes expressed on the extracellular loops of a transmembrane polypeptide of approximately Mr 30000 . In research settings, RUM1 serves as a valuable reagent for reliable detection of the D antigen, including Du variants, and can be utilized in both manual agglutination tests and automated cell grouping systems . Its human origin provides significant advantages over mouse-derived antibodies, as mouse antibodies can trigger human anti-mouse antibody (HAMA) production when used in certain experimental contexts, potentially interfering with results .
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How does RUM1 antibody differ from other anti-D reagents in terms of specificity?
RUM1 exhibits distinct specificity characteristics compared to other anti-D reagents. It reacts as a direct agglutinin with all Rh D positive red cells except those of DVI type, confirming its designated epitope as epD6/7h . Unlike some other anti-D monoclonal antibodies, RUM1 demonstrates positive reactivity with specific variant D phenotypes including HMi, HMii, DFR, DBT, and RoHAr .
When compared with other monoclonal antibodies in additional serologic RhD typing, RUM1 and CI 175-2 showed the highest sensitivity with 97.67% reactivity with weak D samples , making them particularly valuable for detecting challenging weak D phenotypes. This specific reactivity pattern provides researchers with a tool for differentiating between D variants in research applications.
Monoclonal Antibody Reactivity with Weak D DVI Detection Epitope Specificity RUM1 (IgM) 97.67% Negative epD6/7h CI 175-2 97.67% Variable Different epitope P3x61 (IgM) Lower Variable Different epitope MS-26/TH28 Lower Variable Different epitope MS-201 Lower Variable Different epitope -
What is the origin and development history of the RUM1 monoclonal antibody?
RUM1 was developed through a sophisticated process involving the fusion of EBV (Epstein-Barr Virus) transformed B cells with X63Ag8.653 myeloma cells . The B cells were sourced from the peripheral blood of a donor producing high levels of anti-D antibodies. This human heterohybridoma approach differs from traditional mouse hybridoma techniques and results in a fully human monoclonal antibody .
The development methodology represents an important advancement in creating human monoclonal antibodies for research and diagnostic applications. RUM1 (code I-103) was submitted to the third international workshop on monoclonal antibodies against human red cells in Nantes in 1996 , where its characteristics and performance were evaluated alongside other anti-D reagents. This rigorous international evaluation helped establish its reliability and specificity profile for research applications.
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What are the specific epitopes recognized by RUM1 antibody?
RUM1 specifically recognizes the epD6/7h epitope on the Rh D antigen . This epitope specificity explains why RUM1 reacts with most D positive cells but fails to react with the DVI phenotype, which lacks this particular epitope. The antibody's epitope recognition profile extends to several D variants including HMi, HMii, DFR, DBT, and RoHAr , indicating that these variants retain the epD6/7h epitope despite other structural modifications.
Understanding the precise epitope specificity of RUM1 is crucial for researchers working with D variants or mapping epitope distribution across different D phenotypes. The D antigen presents multiple epitopes (at least 30 have been identified), and RUM1's specific recognition pattern provides insights into the structural organization of the D antigen's extracellular domains. This specificity makes RUM1 valuable for epitope mapping studies and for understanding the molecular basis of D antigen variation.
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How does the sensitivity of RUM1 compare to other monoclonal antibodies in D antigen detection?
Comparative analysis of RUM1 with other monoclonal antibodies used in D antigen detection reveals that RUM1 exhibits exceptional sensitivity, particularly for weak D phenotypes. In studies of additional serologic RhD typing with five monoclonal reagents in tube testing, RUM1 and CI 175-2 demonstrated the highest sensitivity with 97.67% reactivity with weak D samples .
This performance data indicates that RUM1 is among the most sensitive reagents available for detecting challenging weak D phenotypes. For researchers working with populations where weak D variants are prevalent, or in studies focusing on D antigen expression levels, RUM1 provides higher detection sensitivity compared to many alternative monoclonal antibodies.
The high sensitivity is particularly relevant in research settings where accurate characterization of D status, including subtle expression variations, is essential. When implementing microcolumn technology, samples with agglutination graded as 3+ or less with RUM1 warrant further investigation, as this cutoff has been shown to effectively identify D variants requiring additional characterization .
