| Purification and Quality Control | The His-tag recombinant protein is purified by affinity chromatography in combination with FPLC columns. The purified P75 C Terminal Region is greater than 90% homogeneous based on SDS-PAGE analysis. |
| Unit Definition (Activity) | 1 unit equals 1 nanogram of purified protein. 20-100 units are sufficient for a ligand binding assay and 100 units are sufficient for a protein-protein interaction assay. |
| Applications | p75 has been applied in in vitro transcription assays, splicing assays, DNA and protein-protein interaction assays. |
| Formulation and Storage | The protein is in 20mM Tris-HCl pH7.9,100mM NaCl, 0.2mM EDTA, 1mM DTT and 20% glycerol. Stored at -70°C before use. Avoid repeated freeze thaw cycles. |
| Synonym | DFS70; LEDGF; MGC74712; p52; PAIP and PSIP2. |
| Protein Sequence | METEQQNKDE GKKPEVKKVE KKRETSMDSR LQRIHAEIKN SLKIDNLDVN RCIEALDELA
SLQVTMQQAQ KHTEMITTLK KIRRFKVSQV IMEKSTMLYN KFKNMFLVGE GDSVITQVLN
KSLAEQRQHE EANKTKDQGK KGPNKKLEKE QTGSKTLNGG SDAQDGNQPQ HNGESNEDSK
DNHEASTKKK PSSEERETEI SLK |
| Background | Lens epithelium-derived growth factor (LEDGF, also called as p75) has been shown to enhance survival of lens epithelial cells (LECs) against stress (1). LEDGF is a transcriptional activator. It protects the cells by binding to cis-stress response ((A/T)GGGG(T/A)), and heat shock (HSE; nGAAn) elements in the stress genes and activating their transcription (2). Originally, it was isolated as a co-activator required for transcriptional activation in human cell-free systems containing RNA polymerase II and general initiation factors (3). LEDGF is expressed at all stages of development in a variety of organs and tissues (4). A second protein product, p52, can be produced from the same gene due to alternative splicing of pre-mRNA. In vitro, p52 was found to be more general and stronger transcriptional co-activator than LEDGF/p75 (3,5). HIV-1 integrase (IN) forms a specific nuclear complex with p75 but not with p52, suggesting a role for p75’s C-terminal region in retroviral integration (6). |
| References | 1. Fatma et al., (2001) J. Biol. Chem. 276, 48899-48907
2. Singh et. Al., (2001) Biochem. Biophys. Res. Commun. 283, 943-955
3. Ge et al., (1998) EMBO J. 17, 6723-6729
4. Cherapanov et al., (2003) J. Biol. Chem. 278, 372-381
5. Ge et al., (1998) Mol. Cell 2, 751-759
6. Maertens et al., (2003) J. Biol. Chem. June 9 Epub ahead of print |
