This short domain is found at the C-terminus of many helicase proteins, including ATP-dependent rRNA helicase SPB4 from Saccharomyces cerevisiae, which is involved in the biogenesis of 60S ribosomal subunits. SPB4 is organised into four domains: dual RecA domains (pfam00270 and pfam00271), a C-terminal extension (CTE, represented by this entry) and a C-terminal tail (pfam23681). This domain packs closely onto the catalytic core and engages the four nucleotides immediately 5' to those within the RNA binding pocket. It shows a mainly alpha- helical structure.
Jiyao W et al.(2023). "The conserved domain database in 2023.",