Zinc-finger RNA-binding protein that destabilizes several cytoplasmic AU-rich element (ARE)-containing mRNA transcripts by promoting their poly(A) tail removal or deadenylation, and hence provide a mechanism for attenuating protein synthesis (PubMed:22701344, PubMed:24700863, PubMed:24733888, PubMed:27102483). Acts as a 3'-untranslated region (UTR) ARE mRNA-binding adapter protein to communicate signaling events to the mRNA decay machinery (By similarity). Functions by recruiting the CCR4-NOT deadenylating complex and components of the cytoplasmic RNA decay machinery to the bound ARE-containing mRNAs, and hence promotes ARE-mediated mRNA deadenylation and decay processes (By similarity). Induces also the degradation of ARE-containing mRNAs even in absence of poly(A) tail (By similarity). Binds to 3'-UTR ARE of numerous mRNAs (PubMed:22701344, PubMed:24700863, PubMed:24733888). Positively regulates early adipogenesis by promoting ARE-mediated mRNA decay of immediate early genes (IEGs) (PubMed:22701344). Promotes ARE-mediated mRNA decay of mineralocorticoid receptor NR3C2 mRNA in response to hypertonic stress (PubMed:24700863). Negatively regulates hematopoietic/erythroid cell differentiation by promoting ARE-mediated mRNA decay of the transcription factor STAT5B mRNA (By similarity). Positively regulates monocyte/macrophage cell differentiation by promoting ARE-mediated mRNA decay of the cyclin-dependent kinase CDK6 mRNA (By similarity). Promotes degradation of ARE-containing pluripotency-associated mRNAs in embryonic stem cells (ESCs), such as NANOG, through a fibroblast growth factor (FGF)-induced MAPK-dependent signaling pathway, and hence attenuates ESC self-renewal and positively regulates mesendoderm differentiation (PubMed:24733888). May play a role in mediating pro-apoptotic effects in malignant B-cells by promoting ARE-mediated mRNA decay of BCL2 mRNA (By similarity). In association with ZFP36L2 maintains quiescence on developing B lymphocytes by promoting ARE-mediated decay of several mRNAs encoding cell cycle regulators that help B cells progress through the cell cycle, and hence ensuring accurate variable-diversity-joining (VDJ) recombination and functional immune cell formation (PubMed:27102483). Together with ZFP36L2 is also necessary for thymocyte development and prevention of T-cell acute lymphoblastic leukemia (T-ALL) transformation by promoting ARE-mediated mRNA decay of the oncogenic transcription factor NOTCH1 mRNA (PubMed:20622884). Involved in the delivery of target ARE-mRNAs to processing bodies (PBs) (By similarity). In addition to its cytosolic mRNA-decay function, plays a role in the regulation of nuclear mRNA 3'-end processing; modulates mRNA 3'-end maturation efficiency of the DLL4 mRNA through binding with an ARE embedded in a weak noncanonical polyadenylation (poly(A)) signal in endothelial cells (By similarity). Also involved in the regulation of stress granule (SG) and P-body (PB) formation and fusion (By similarity). Plays a role in vasculogenesis and endocardial development (PubMed:15226444, PubMed:17013884). Involved in the regulation of keratinocyte proliferation, differentiation and apoptosis (By similarity). Plays a role in myoblast cell differentiation (PubMed:17889962). Associates with the cytoplasmic CCR4-NOT deadenylase and RNA exosome complexes to trigger ARE-containing mRNA deadenylation and decay processes. Interacts with CNOT1. Interacts (via N-terminus) with CNOT6. Interacts with CNOT7; this interaction is inhibited in response to phorbol 12-myristate 13-acetate (PMA) treatment in a p38 MAPK-dependent manner. Interacts with DCP1A. Interacts (via N-terminus) with DCP2. Interacts (via N-terminus) with EXOSC2. Interacts with XRN1. Interacts (via phosphorylated form) with YWHAB; this interaction occurs in a protein kinase AKT1-dependent manner (By similarity). Interacts (via phosphorylated form) with YWHAZ; this interaction occurs in a p38 MAPK- and AKT-signaling pathways (PubMed:22701344). Shuttles between the nucleus and the cytoplasm in a XPO1/CRM1-dependent manner (PubMed:11796723). Component of cytoplasmic stress granules (By similarity). Localizes in processing bodies (PBs) (By similarity). Expressed in preadipocytes and adipocytes (PubMed:22701344). Expressed in the proximal and distal tubules in the renal cortex (at protein level) (PubMed:24700863). Expressed in ovary, heart, kidney, lung, spleen and thymus (PubMed:15226444). Weakly expressed in brain, liver and testis (PubMed:15226444). Expressed in osteoblasts (PubMed:15465005). Expressed in embryonic stem cells (ESCs) (PubMed:24733888). Expressed through B lymphocyte development (PubMed:27102483). Expressed in embryos at 8 dpc, onward (PubMed:15226444). Expressed in the allantois and throughout the neuroectoderm and paraxial mesoderm at 8 dpc (PubMed:15226444). Expressed in the chorion and blood vessels at 8.5 dpc (PubMed:17013884). Expressed in the neural tube, paraxial mesoderm, heart, brain, otic vesicle and yolk sac at 9.5 dpc (PubMed:17013884). Expressed in embryonic stem cells (ESC) (PubMed:15226444). Up-regulated during myogenic differentiation in a p38 MAPK-dependent manner (PubMed:17889962). Up-regulated in response to fibroblast growth factor FGF4 in embryonic stem cells (ESCs) in a p38 MAPK-dependent manner (PubMed:24733888). Up-regulated during high sodium diet-fed in the renal tubules (PubMed:24700863). Up-regulated upon hypertonic stress condition with raffinose (at protein level) (PubMed:24700863). Up-regulated by parathyroid hormone (PTH) in calvarial osteoblasts (PubMed:15465005). Up-regulated in response to adrenocorticotropic hormone (ACTH) (PubMed:19179481). Up-regulated in response to cAMP (PubMed:19179481). Down-regulated by bone morphogenetic protein BMP2 treatment in calvarial osteoblasts (PubMed:15465005). Down-regulated during the conversion from quiescence to activated satellite cells upon muscle injury (PubMed:23046558, PubMed:25815583). Phosphorylated (PubMed:19179481). Phosphorylated by RPS6KA1 at Ser-334 upon phorbol 12-myristate 13-acetate (PMA) treatment; this phosphorylation results in dissociation of the CCR4-NOT deadenylase complex and induces p38 MAPK-mediated stabilization of the low-density lipoprotein receptor LDLR mRNA. Phosphorylated by protein kinase AKT1 at Ser-92 and Ser-203 in response to insulin; these phosphorylations stabilize ZFP36L1, increase the association with 14-3-3 proteins and mediate ARE-containing mRNA stabilization. AKT1-mediated phosphorylation at Ser-92 does not impair ARE-containing RNA-binding. Phosphorylated at Ser-54, Ser-92 and Ser-203 by MAPKAPK2; these phosphorylations increase the association with 14-3-3 proteins and mediate ARE-containing mRNA stabilization in a protein kinase AKT1-independent manner. MAPKAPK2-mediated phosphorylations at Ser-54, Ser-92 and Ser-203 do not impair ARE-containing RNA-binding (By similarity). Phosphorylations increase the association with 14-3-3 proteins and mediate ARE-containing mRNA stabilization during early adipogenesis in a p38 MAPK- and AKT-dependent manner (PubMed:22701344). Ubiquitinated. Ubiquitination leads to proteasomal degradation, a process inhibited by phosphorylations at Ser-90, Ser-92 and Ser-203. Embryos die in utero at 11 dpc (PubMed:15226444, PubMed:17013884). Exhibit extraembryonic, intraembryonic, vascular and neural tube defects and cardiac abnormalities at 9.5 dpc (PubMed:17013884). Show a reduced number of circulating blood cells (PubMed:17013884). Show failure of chorioallantoic fusion (PubMed:15226444). Exhibited increased level of VEGFA protein level in embryonic fibroblasts under both normoxic and hypoxic conditions (PubMed:17013884). Knockout mice lacking both ZFP36L1 and ZFP36L2 during thymopoiesis lead to aberrant T cell development and subsequently develop a T-cell acute lymphoblastic leukemia (T-ALL) (PubMed:20622884). Show also higher levels of NOTCH1 protein and mRNA in thymocytes (PubMed:20622884). Conditional knockout mice of both ZFP36L1 and ZFP36L2 in pro-B cells display reduced B lymphocyte number and delayed variable-diversity-joining (VDJ) recombination (PubMed:27102483). Exhibit also increased protein and ARE-containing mRNA expressions of several factors implicated in cell cycle progression in late pre-B cells (PubMed:27102483).