pfam10715: REGB_T4 (This model is not part of the current CDD release)
T4-page Endoribonuclease RegB
The RegB endoribonuclease encoded by bacteriophage T4 is a unique sequence-specific nuclease that cleaves in the middle of GGAG or, in a few cases, GGAU tetranucleotides, preferentially those found in the Shine-Dalgarno regions of early phage mRNAs. Phage RB49 in addition to RegB utilizes Escherichia coli endoribonuclease E for the degradation of its transcripts for gene regB. The deduced primary structure of RegB proteins of 32 phages studied is almost identical to that of T4, while the sequences of RegB encoded by phages RB69, TuIa and RB49 show substantial divergence from their T4 counterpart. Rebuilding from the PDB:2hx6 structure, this family does not fall into the Lysozyme-like family, but rather is a new member of the RelE/YoeB structural and functional family of ribonucleases specialising in mRNA inactivation within the ribosome.
Jiyao W et al.(2023). "The conserved domain database in 2023.",