Electrophoretic Mobility Shift Assay (EMSA) Experiment Service

Instruction manual

First Edition (Revised on April, 2016)


Electrophoretic Mobility Shift Assay (EMSA), also called gel retardation assay. It is an important experimental method to study the interaction of nucleic acid and protein, it is commonly used to verify the interaction of transcription factors and promoter. This assay is based on the principle that the migration rate of nucleic acid-protein complexes is significantly reduced in the Native-PAGE. The probes of specific and non-specific are designed, and these probes can combine with the target protein by incubation. Due to the formation of probe-protein complex, its molecular mass will increase, so, in SDS-PAGE, the migration rates of complex are reduced compared with the probes which are not combined with protein. Because there are some special markers in the probes, the bands can be shown in the position of probe-protein complex by trans-membrane, coloration or exposure, then, the interaction of nucleic acid and protein could be proved. With the advancement of experimental technology, the experiment could detect the target qualitatively and quantitatively.


Procedure of experimentSchedule timeCharacteristics
1. Sample preparationAccording to the discussion between customers and tech support1. Several kinds of recombinant protein expression methods are provided, such as prokaryotic expression, yeast expression, virus-insect cell expression and mammalian cells expression, etc..
2. The enrichment and purification service of target protein in natural samples are provided.
3. The lysis buffers which are used for extraction of cytoplasmic protein and nuclear protein are provided. It is mild, high-efficient and possess low damage for protein.
2. Synthesis and preparation of probe1-2weeks1. Artificial synthesized probes are provided.
2. Probe labeling: several non-isotopic labeling is provided, such as DIG, Biotin and Cy5, etc..
3. Lots of services that are based on EMSA are provided, such as Super-Shift EMSA and double fluorescence EMSA, etc..
3. Incubation of  probe and sample
4. 6.5% Native-PAGE preparation and electrophoresis
5. Trans-membrane
6. Detection

1. All of experimental projects should obey the law.
2. All samples should not be contagious.
3. Personalized experimental scheme could be customized according to customers’ needs.