C-terminal deadenylase domain of CCR4a, also known as CCR4-NOT transcription complex subunit 6
This subfamily contains the C-terminal catalytic domain of the deadenylase, CCR4a, also known as CCR4-NOT transcription complex subunit 6 (CNOT6). CCR4 belongs to the large EEP (exonuclease/endonuclease/phosphatase) superfamily that contains functionally diverse enzymes that share a common catalytic mechanism of cleaving phosphodiester bonds. CCR4 is the major deadenylase subunit of the CCR4-NOT transcription complex, which contains two deadenylase subunits and several noncatalytic subunits. The other deadenylase subunit, Caf1, is a DEDD-type protein and does not belong in this superfamily. There are two vertebrate CCR4 proteins, CCR4a and CCR4b (also called CNOT6-like or CNOT6L). CCR4a associates with other components, such as CNOT1-3 and Caf1, to form a CCR4-NOT multisubunit complex, which regulates transcription and mRNA degradation. The nuclease domain of CCR4a exhibits Mg2+-dependent deadenylase activity with specificity for poly (A) RNA as substrate. CCR4a is a component of P-bodies and is necessary for foci formation of various P-body components. It also plays a role in cellular responses to DNA damage, by regulating Chk2 activity.
Jiyao W et al.(2023). "The conserved domain database in 2023.",