Article

The RCC1 protein, a regulator for the onset of chromosome condensation locates in the nucleus and binds to DNA

Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Fukuoka, Japan.
The Journal of Cell Biology (Impact Factor: 9.83). 11/1989; 109(4 Pt 1):1389-97.
Source: PubMed

ABSTRACT

The RCC1 gene, a regulator for the onset of chromosome condensation was found to encode a protein with a molecular mass of 45 kD, determined using the antibody against the synthetic peptides prepared according to the amino acid sequence of the putative RCC1 protein. The p45 located in the nuclei was released from the isolated nuclei, either by DNase I digestion or by treatment with 0.3 M NaCl. Consistently, p45 bound to the DNA-cellulose column was eluted with 0.3 M NaCl. After sequential treatment with DNase I and 2 M NaCl, almost all of the RCC1 protein were released from the nuclei. Thus, RCC1 protein locates on the chromatin and is not a component of the nuclear matrix. In mitotic cells, p45 is dispersed into the cytoplasm. Presumably, RCC1 protein plays a role in regulating the onset of chromosome condensation, at the level of transcription or of mRNA maturation.

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    • "In this way, RanGAP1 activity is concentrated at the cytoplasmic side of the NPC. On the other hand, RanGEF/RCC1, which converts Ran-GDP to Ran-GTP, is a chromatin-associated protein and its activity is concentrated in the nucleus (Ohtsubo et al., 1987Ohtsubo et al., , 1989; Bischoff and Ponstingl, 1991a,b;Figure 1A). This biased localization of RanGAP1 and RanGEF/RCC1 generates the gradient of Ran-GTP between the nucleus and the cytoplasm. "
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    • "Both systems utilize open mitosis, where the nuclear envelope breaks down fully and cytoplasmic and nuclear contents— including Ran—mingle during mitosis (Hutchins et al., 2009). RCC1 binds to chromatin (Ohtsubo et al., 1989; England et al., 2010), and through its interaction with Histones (Nemergut et al., 2001; Makde et al., 2010) and DNA (Chen et al., 2007), generates a locally high concentration of Ran.GTP (Bischoff and Ponstingl, 1991). As Ran.GTP diffuses away from the chromatin, RanGAP induces GTP hydrolysis, and Ran.GTP is converted to Ran.GDP (Kalab and Heald, 2008); an activity enhanced by RanBP1 (Seewald et al., 2003). "
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