In bacteria, the restart of stalled DNA replication forks requires the DNA helicase PriA. PriA can recognize and remodel abandoned DNA replication forks, unwind DNA in the 3'-to-5' direction, and facilitate the loading of the helicase DnaB onto the DNA to restart replication. ssDNA-binding protein (SSB) is typically present at the abandoned forks, protecting the ssDNA from nucleases. Research that is based on the assays for junction dissociation, surface plasmon resonance, single-molecule FRET, and x-ray crystal structure has revealed the helicase activity of PriA, the SSB-PriA interaction, and structural information of PriA helicase. Here, we used Atomic Force Microscopy (AFM) to visualize the interaction between PriA and DNA substrates with or without SSB in the absence of ATP to

In the last several years, as evidence of a surged number of GPCR-G complex structures, the expressions of GPCRs and G proteins for structural biology have achieved tremendous successes, mostly in insect and mammalian cell systems, resulting in more than 370 structures of over 70 GPCRs have been resolved. However, the challenge remains, particularly in the conformational transition and dynamics study area where a much higher quantity of the receptors and G proteins is required even in comparison to X-ray and cryo-EM (5 mg/ml, 3 μl/sample) when NMR spectroscopy (5 mg/ml, 250 μl /sample) is applied. As a result, the expression levels of the insect and mammalian systems are also difficult to meet this demand, not to mention the prohibitive cost of producing GPCRs and G proteins using