Human MutL Homolog 1 (MLH1) ELISA Kit

Principle of the Assay

The microtiter plate provided in this kit has been pre-coated with an antibody specific to MLH1. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated antibody preparation specific to MLH1. Next, Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. After the TMB substrate solution is added, only those wells that contain MLH1, biotin-conjugated antibody, and enzyme-conjugated Avidin will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of sulphuric acid solution, and the color change is measured spectrophotometrically at a wavelength of 450nm ± 10nm. The concentration of MLH1 in the samples is then determined by comparing the O.D. of the samples to the standard curve.

For Use with serum, plasma, and cell culture supernatants. For Research Use Only. Not for use in diagnostic procedures.

Target Information

Heterodimerizes with PMS2 to form MutL alpha, a component of the post-replicative DNA mismatch repair system (MMR). DNA repair is initiated by MutS alpha (MSH2-MSH6) or MutS beta (MSH2-MSH3) binding to a dsDNA mismatch, then MutL alpha is recruited to the heteroduplex. Assembly of the MutL-MutS-heteroduplex ternary complex in presence of RFC and PCNA is sufficient to activate endonuclease activity of PMS2. It introduces single-strand breaks near the mismatch and thus generates new entry points for the exonuclease EXO1 to degrade the strand containing the mismatch. DNA methylation would prevent cleavage and therefore assure that only the newly mutated DNA strand is going to be corrected. MutL alpha (MLH1-PMS2) interacts physically with the clamp loader subunits of DNA polymerase III, suggesting that it may play a role to recruit the DNA polymerase III to the site of the MMR. Also implicated in DNA damage signaling, a process which induces cell cycle arrest and can lead to apoptosis in case of major DNA damages. Heterodimerizes with MLH3 to form MutL gamma which plays a role in meiosis.

GENE ID	4292
SWISS PROT	P40692
SYNONYMS	COCA2; FCC2; HNPCC; HNPCC2; hMLH1; DNA mismatch repair protein Mlh1

Materials Supplied

Kit Components	96 Wells Quantity/Size
Pre-coated, ready-to-use 96-well strip plate	1 plate
Plate sealer for 96 wells	2
Standard	2 tubes
Diluent buffer	1 bottle
Detection Reagent A	1 bottle
Detection Reagent B	1 bottle
TMB Substrate	1 tube
Stop Solution	1 tube
Wash Buffer (30 ℅ concentrate)	1 tube
Product data sheet	1 copy

Storage

The TMB Substrate, Wash Buffer (30X concentrate), and the Stop Solution should be stored at 4°C upon receipt, while the other items should be stored at -20°C.

Performance Characteristics

REPEATABILITY	Intra-assay Precision (Precision within an assay): 3 samples with low, middle, and high-level MLH1 were tested 20 times on one plate, respectively. Inter-assay Precision (Precision between assays): 3 samples with low, middle, and high-level MLH1 were tested on 3 different plates, with 8 replicates in each plate. CV(%) = SD/meanX100 Intra-Assay: CV<10% Inter-Assay: CV<12%
SENSITIVITY	The minimum detectable dose was 0.057ng/mL.
ASSAY RANGE	0.156-10ng/mL
SPECIFICITY	This assay has high sensitivity and excellent specificity for the detection of MLH1. No significant cross-reactivity or interference between MLH1 and analogs was observed. Note: Limited by current skills and knowledge, it is impossible to perform all possible cross-reactivity detection tests between MLH1 and all analogs, therefore, cross reactivity may still exist.