Cellular fractionation of mouse INSM1 protein in βTC-1 cells. Approximately 15 μg of proteins isolated from whole cell (WC) lysate, mitochondria, microsome, cytosol, and nuclear extract fractions were separated on 12% SDS-PAGE, transferred to a nitrocellulose membrane, and blotted with affinity purified rabbit polyclonal INSM1 antibody. The mouse INSM1 protein, approximately 58 kDa in size, is found in the whole cell lysate and the nuclear fraction. Nonspecific minor bands are observed in several of the fractions.