A selective and sensitive detection system for 4-thiouridine modification in RNA

(A) Purified ThiI (2.0 µg; left) and IscS (2.0 µg; right) were analyzed by 15% SDS-PAGE. The gels were stained with Coomassie brilliant blue. (B) Sequence of E. coli tRNA^Phe transcript. (C) Formation of s⁴U in E. coli tRNA^Phe transcript by ThiI was detected using the MTSEA biotin-XX s⁴U detection system. In the absence of ATP, s⁴U formation did not occur (negative control). In contrast, in the presence of 2 mM ATP, time-dependent s⁴U formation was observed by the MTSEA biotin-XX s⁴U detection system.