Arabidopsis <i>rad23-4</i> gene is required for pollen development under UV-B light

Abstract

Nucleotide excision repair (NER) is a highly conserved DNA repair pathway for correcting DNA lesions that cause distortion of the double helical structure. The protein heterodimer Rad23 is involved in recognition and binding to such lesions. Here, we showed that rad23-4 (AT5g38470) was expressed in the roots, mature leaves, floral buds and developing siliques. The collapsed pollen grains were observed in ultraviolet (UV)-B–treated rad23-4 mutants. Compared with the wild type (WT), the rad23-4 mutants has decreased pollen germination efficiency (11.7-17.3%) and increased seeds abortion rate (12.5-18.9%). Furthermore, the rad23-4 mutants has decreased anthocyanin production and showed changes in the expression of several NER homologous genes, including Rad4, Rad10, and Rad16. Our studies identified a previously uncharacterized role of rad23-4 gene in regulating the pollen development and seed abortion, which is important for understanding the precise processes of NER in plant.

Keywords: Nucleotide excision repair (NER), rad23-4 gene, anthocyanin, pollen grains, seeds abortion