Self-polymerization of archaeal RadA protein into long and fine helical filaments |
| |
Authors: | Lee Ming-Hui Leng Chih-Hsiang Chang Yuan-Chih Chou Chia-Cheng Chen Yi-Kai Hsu Fu-Fei Chang Chia-Seng Wang Andrew H-J Wang Ting-Fang |
| |
Institution: | Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan, ROC. |
| |
Abstract: | The Archaeal protein RadA, a RecA/Rad51 homolog, is able to promote pairing and exchange of DNA strands with homologous sequences. Here, we have expressed, purified, and crystallized the catalytically active RadA protein from Sulfolobus solfataricus (Sso). Preliminary X-ray analysis indicated that Sso RadA protein likely forms helical filament in protein crystals. Using atomic force microscopy with a carbon nanotube (CNT) tip for high-resolution imaging, we demonstrated that Sso RadA protein indeed forms fine helical filaments up to 1 microm in length ( approximately 10nm pitch) in the absence of DNA and nucleotide cofactor. We also observed that Sso RadA protein helical filament could dissemble upon incubation with ssDNA, and then the proteins associate with ssDNA to form nucleoprotein filament. |
| |
Keywords: | RadA Homologous recombination AFM Rad51 RecA Dmc1 |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|