Enables mRNA 3'-UTR binding activity; poly(U) RNA binding activity; and transcription corepressor activity. Involved in several processes, including cell fate specification; embryonic pattern specification; and negative regulation of transcription by RNA polymerase II. Located in P granule. Expressed in several structures, including Psub4; germ line; neurons; oocyte; and rectal gland cell. Human ortholog(s) of this gene implicated in breast cancer. Is an ortholog of human ZFP36 (ZFP36 ring finger protein); ZFP36L1 (ZFP36 ring finger protein like 1); and ZFP36L2 (ZFP36 ring finger protein like 2).