The A20 proteins have a novel class of Cys2/Cys2 zinc finger domain. It may be present in tandem repeat or singularly. In animals it has been shown to modulate NF-kB signaling pathway. Recently it has been shown that 4-ZnF domain in A20 interact with K63-linked Ub. But weather this domain can bind to DNA directly is not determine yet and specific function of A20 Znf proteins in plant is also yet to be reported.
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