| dc.description.abstract | Chloroplasts have to divide to maintain their numbers throughout cycles of cell division by binary fission and conduct photosynthesis and fulfill other metabolic functions that are essential to plant life. Chloroplast division is achieved by complex division machinery including contractile inner ring: Z-ring and other regulatory proteins. ARC6 is one of the key regulatory proteins which are known to stabilize or maintain Z-ring and anchor it to the inner membrane by interaction with FtsZ2. However, the underlying mechanism of this modulation is unclear to date. Here, we performed biochemical characterization of ARC6 with three complementary techniques, namely 90° light scattering, sedimentation and transmission electron microscopy.
Our data have shown stromal portion of ARC6 (tARC6) affects FtsZ2 assembly without forming higher order structures, and exerts it role by FtsZ2 dynamics. Interestingly, tARC6 prevented GDP induced FtsZ2 disassembly and has shown significant effect on FtsZ2 assembly when GDP was present. 3D reconstruction was also performed to elucidate structural basis and investigate binding model with FtsZ2 protofilament and PDV2. Together, our data reveal that dimeric form of tARC6 binds to FtsZ2 filaments and prevent GDP associated FtsZ2 disassembly thereby facilitate FtsZ2 assembly. | en |
