Fig. 8.

The 20 amino acids at the CTPsyn N-terminal are required for co-assembly into cytoophidia. (A) Schematic diagram showing CTPsyn-CTPsynB chimeric constructs wherein either aa 1–56 or aa 21–56 of CTPsyn is appended at the N-terminal of CTPsynB resulting in ^{CTPsyn/1–56}CTPsynB and ^{CTPsyn/21–56}CTPsynB constructs, respectively. (B-B′′) Cell expressing CTPsyn-mCherry and CTPsynB-Venus show distinct cytoplasmic distribution of both proteins. However, co-expression of Venus-tagged ^{CTPsyn/1–56}CTPsynB (C) and CTPsyn-mCherry (C′) results in the formation of clusters containing both proteins (C-C′′) which organise into filaments in the presence of DON (D-D′′). ^{CTPsyn/21–56}CTPsynB protein, on the other hand, forms an aggregate-like structure distinct from the CTPsyn filament (E-E′′) and is unaffected by DON treatment (F-F′′). DNA staining is shown in blue while the Venus- and mCherry-tagged proteins are in green and red, respectively. Scale bar=5 µm.