Experimental techniques for studying protein-DNA interaction are classified into two forms, namely in vitro and in vivo. In vivo studies are useful because they preserve the natural structure of the interaction edges. However, in multiproteins, it is difficult to understand which part of the protein is directly connected to the DNA and protects it. The in vitro study is instead suitable on purified proteins and protein subunits. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay In the late 1960s, the first studies on DNA-protein interactions were conducted. Nitrocellulose filter binding tests were the first technique offered for this purpose. In the 1990s, many different experimental techniques were developed to study DNA-protein interactions. To date, numerous techniques are available for the detection and characterization of protein-nucleic acid complexes, and most have advantages and disadvantages. Such techniques include but are not limited to Electrophoretic Mobility Shift Assays (EMSA) (Fried 1989), DNase I Footprinting (Brenowitz et al. 1986), Bacterial One-hybrid System, and techniques based on chromatin immunoprecipitation (ChIP) analysis. , e.g., chromatin immunoprecipitation with DNA microarray (ChIP-chip; Lieb et al. 2001), chromatin immunoprecipitation sequencing (ChIP-Seq; Johnson et al. 2007), ChIP-exo (Pugh 2012) have been used ) and chromatin immunoprecipitation tags (ChIP-PET; Wu et al. 2013). Many techniques are available for the detection and characterization of protein-nucleic acid complexes, and most have advantages and disadvantages in determining and characterizing the DNA-protein relationship. Electrophoretic mobility shift assays (EMSA); Electrophoretic mobility shift assays (also known as "band shift assays" and "mobility shift electrophoresis") have a standard protocol for studying a wide range of nucleic acid-protein interactions, from binding events of single proteins to the assembly of large complexes such as the spliceosome (Malloy 2000; Rio 2014). The EMSA technique was originally introduced by Fried in 1989 and many variations have been described in the literature today. EMSA is a simple, rapid and very sensitive laboratory technique for qualitatively testing the specific nucleic acid/protein interaction, although, under appropriate conditions, it is used for quantitative purposes. However, EMSA is not without limitations and more important limitations and problems have been found (Hellman and Fried 2007). This technique is based on the observation that segments that bind nucleic acid to proteins cause a decrease in the electrophoretic mobility of the segment compared to free nucleic acid in agarose gel under native conditions or in non-denaturing polyacrylamide gel (Vinckevicius and Chakravarti, 2012; Rio 2014). In this technique the crude protein mixture or purified proteins are mixed with the nucleic acid sequence in a suitable buffer and specific binding, stable complexes of nucleic acid and protein are allowed (the probe can be bound in nonspecifically from other proteins) are separated by non-denaturing gel electrophoresis; not only for studying nucleic acid sequence binding requirements, but also for several aspects of nucleic acid-protein interaction, including but not limited to, binding kinetics (such as affinity constants), protein identification and characterization ​ligands and cofactor requirements. A wide variety of nucleic acid and protein lengths (lengths from short oligonucleotides/amino acids to several thousand) and structures.