FIGURE 2.
Arx1p shuttles rapidly between nucleus and cytoplasm. (A) One nucleus of a heterokaryon (outlined) expressing Arx1p–GFP was bleached four times every 225 sec. The fluorescence intensity in both nuclei was recorded at 15-sec time points (graph on the right). A representative set of frames is shown. An arrow indicates the control nonbleached nucleus in a neighboring cell. (B) To control for cytoplasmic pool of Arx1p–GFP and de novo protein synthesis, both nuclei of heterokaryon were bleached and fluorescence intensity in both nuclei was followed by an 11-sec interval.
