Rex-1 (Reduced Expression Protein 1, Zinc Finger Protein 42, ZFP42)

Human Rex-1 (also Zfp-42) is a 35kD zinc finger family transcription factor that is highly expressed in human embryonic stem cells. It is one of several gene markers used to identify human stem cells. It is 310 amino acids in length and contains a zinc finger-binding domain between aa214-307. Over this region, human and mouse show modest homology with 47% amino acid identity. ||Applications: |Suitable for use in Immunocytochemistry, Western Blot and ELISA. Other applications not tested.||Recommended Dilution:|Immunocytochemistry: 10ug/ml was used to detect REx-1 on NTERA2 cells. Cells were fixed with PBS, 4% paraformaldehyde for 20 minutes at RT and blocked with PBS, 10% normal donkey serum, 0.1% Triton X-100, 1% BSA for 45 minutes at RT. After blocking, cells were incubated with diluted R1992-45 overnight at 4°C followed by Rhodamine Red-coupled anti-rat IgG at RT in the dark for one hour. Between each step, cells were washed with PBS, 0.1% BSA.|Western Blot: 1-2ug/ml. Using a colorimetric detection system, the detection limit is ~10ng/lane and under non-reducing and reducing conditions. ECL detection will increase sensitivity by 5 to 50 fold.|Direct ELISA: 0.5-1ug/ml. The detection limit is ~1ng/well.|Optimal dilutions to be determined by the researcher.||Storage and Stability:|Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with sterile PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.