The effects of enhanced UV-B radiation on the RCC1 in wheat somatic cells

Abstract

Regulator of Chromosome Condensation 1 (RCC1), a Guanine Nucleotide Exchange Factor (GEF) for the small Ran GTPase (Ran-GTP), is localized on chromatin in the nucleus where it mediates the generation of Ran-GTP. The production of Ran-GTP by RCC1 is critical for nuclear envelope formation, nucleocytoplasmic transport, DNA replication, and chromosome-induced mitotic spindle assembly. Most of the previous studies on RCC1 were carried out in mammalian cells. Only few studies on RCC1 in plant cell have been reported. Here we present an investigation on the identification of RCC1 and its location in wheat (Triticum aestivum L.) somatic cells during mitosis using immunoblotting and immunofluorescence. It was assumed that RCC1 was richer in chromatin than the surrounding cytoplasm throughout mitosis. Compared with white light, enhanced UV-B radiation greatly reduced the content of RCC1 (immunoblotting) and its fluorescence intensity. When RCC1 was absent, laser scanning confocal microscope detected the abnormal chromosomes. The results indicate that the participation of RCC1 in cell cycle provides theoretical ground for revealing the mechanism of abnormal mitosis caused by enhanced UV-B radiation and are of practical significance for agricultural production.