Skip to main content
. 2022 Nov 30;8(48):eadd2536. doi: 10.1126/sciadv.add2536

Fig. 3. CHIKV RNA replication spherule structures revealed by cryo-ET.

Fig. 3.

(A) Tomographic slice of cell periphery depicting CHIKV RNA replication spherules at the PM. Scale bar, 50 nm. (B) Corresponding 3D segmentation of cellular features. See also movie S1. (C) Snapshot of the individual spherules. Yellow arrows measure the ordered density within the center of the cytoplasmic ring. Green arrows mark the additional associated density proximal to the RC cytoplasmic ring. (D) CHIKV spherule 3D volume is determined by subtomogram averaging with imposed C12 symmetry. (E) The RC core complex (nsP1 + 2 + 4) is fitted into the C1 subtomogram average map of the RC. A cytoplasmic ring as observed in (C), likely made of nsP3, RNA, and host factors remain loosely connected to the nsP1 ring, which is bound at the neck of the spherule. The extra density above the nsP2h region is likely to be the C-terminal protease of nsP2, stabilized or restrained by the cytoplasmic ring.