Fig. 9. A fraction of KIN17 protein is associated with chromatin and nuclear matrix. Testicular nuclear matrix was prepared as described in the Materials and Methods. Proteins were sequentially extracted with 0.5% Triton X-100 (lane1), DNase I and 0.25 M (NH4)2 SO4 (chromatin, lane 2) and 2 M NaCl (lane 3); the remaining pellet was solubilised in 8 M urea buffer (nuclear matrix, lane 4). 50 µg of protein from each step of the extraction protocol were subjected to SDS-PAGE and immunoblotted with antibodies against KIN17 protein, PCNA or LAMIN B (Santa Cruz Biotechnology) or SF2/ASF (gift from A. Krainer).