Specifically recognizes and binds N6-methyladenosine (m6A)-containing RNAs, and regulates their stability (PubMed:24284625, PubMed:26046440, PubMed:26318451, PubMed:32492408). M6A is a modification present at internal sites of mRNAs and some non-coding RNAs and plays a role in mRNA stability and processing (PubMed:22575960, PubMed:24284625, PubMed:32492408, PubMed:25412658, PubMed:25412661). Acts as a regulator of mRNA stability by promoting degradation of m6A-containing mRNAs via interaction with the CCR4-NOT and ribonuclease P/MRP complexes, depending on the context (PubMed:24284625, PubMed:26046440, PubMed:27558897, PubMed:30930054, PubMed:32492408). The YTHDF paralogs (YTHDF1, YTHDF2 and YTHDF3) share m6A-containing mRNAs targets and act redundantly to mediate mRNA degradation and cellular differentiation (PubMed:28106072, PubMed:32492408). M6A-containing mRNAs containing a binding site for RIDA/HRSP12 (5'-GGUUC-3') are preferentially degraded by endoribonucleolytic cleavage: cooperative binding of RIDA/HRSP12 and YTHDF2 to transcripts leads to recruitment of the ribonuclease P/MRP complex (PubMed:30930054). Other m6A-containing mRNAs undergo deadenylation via direct interaction between YTHDF2 and CNOT1, leading to recruitment of the CCR4-NOT and subsequent deadenylation of m6A-containing mRNAs (PubMed:27558897). Required maternally to regulate oocyte maturation: probably acts by binding to m6A-containing mRNAs, thereby regulating maternal transcript dosage during oocyte maturation, which is essential for the competence of oocytes to sustain early zygotic development (By similarity). Also required during spermatogenesis: regulates spermagonial adhesion by promoting degradation of m6A-containing transcripts coding for matrix metallopeptidases (By similarity). Also involved in hematopoietic stem cells specification by binding to m6A-containing mRNAs, leading to promote their degradation (PubMed:30065315). Also acts as a regulator of neural development by promoting m6A-dependent degradation of neural development-related mRNA targets (By similarity). Inhibits neural specification of induced pluripotent stem cells by binding to methylated neural-specific mRNAs and promoting their degradation, thereby restraining neural differentiation (PubMed:32169943). Regulates circadian regulation of hepatic lipid metabolism: acts by promoting m6A-dependent degradation of PPARA transcripts (PubMed:30428350). Regulates the innate immune response to infection by inhibiting the type I interferon response: acts by binding to m6A-containing IFNB transcripts and promoting their degradation (PubMed:30559377). May also act as a promoter of cap-independent mRNA translation following heat shock stress: upon stress, relocalizes to the nucleus and specifically binds mRNAs with some m6A methylation mark at their 5'-UTR, protecting demethylation of mRNAs by FTO, thereby promoting cap-independent mRNA translation (PubMed:26458103). Regulates mitotic entry by promoting the phase-specific m6A-dependent degradation of WEE1 transcripts (PubMed:32267835). Promotes formation of phase-separated membraneless compartments, such as P-bodies or stress granules, by undergoing liquid-liquid phase separation upon binding to mRNAs containing multiple m6A-modified residues: polymethylated mRNAs act as a multivalent scaffold for the binding of YTHDF proteins, juxtaposing their disordered regions and thereby leading to phase separation (PubMed:31388144, PubMed:31292544, PubMed:32451507, PubMed:31642031). The resulting mRNA-YTHDF complexes then partition into different endogenous phase-separated membraneless compartments, such as P-bodies, stress granules or neuronal RNA granules (PubMed:31292544). May also recognize and bind RNAs modified by C5-methylcytosine (m5C) and act as a regulator of rRNA processing (PubMed:31815440). (Microbial infection) Promotes viral gene expression and replication of polyomavirus SV40: acts by binding to N6-methyladenosine (m6A)-containing viral RNAs (PubMed:29447282). (Microbial infection) Promotes viral gene expression and virion production of kaposis sarcoma-associated herpesvirus (KSHV) at some stage of the KSHV life cycle (in iSLK.219 and iSLK.BAC16 cells) (PubMed:29659627). Acts by binding to N6-methyladenosine (m6A)-containing viral RNAs (PubMed:29659627). Interacts with CNOT1; interaction is direct and promotes recruitment of the CCR4-NOT complex (PubMed:27558897, PubMed:32492408). Interacts with YTHDF3 (PubMed:28106072). Interacts with RIDA/HRSP12; interaction leads to recruitment of the ribonuclease P/MRP complex (PubMed:30930054). Localizes to the cytosol and relocates to the nucleus following heat shock stress (PubMed:26458103). Can partition into different structures: into P-bodies in unstressed cells, and into stress granules during stress (PubMed:31292544). Highly expressed in induced pluripotent stem cells (iPSCs) and down-regulated during neural differentiation. Following heat shock stress. The disordered regions have the ability to interact with each other and to 'phase separate' into liquid droplets within the cytosol following binding to mRNAs containing multiple m6A-modified residues (PubMed:31292544). This leads to the partition of m6A-containing mRNAs into membraneless compartments, where mRNAs may be stored, degraded or used to transport mRNAs to dendritic arbors in neurons (PubMed:31292544). Ubiquitinated by the SCF(SKP2) complex, leading to its degradation. Belongs to the YTHDF family. YTHDF2 subfamily. The role of YTHDF2 and N6-methyladenosine (m6A) in virus expression and replication is unclear (PubMed:29109479, PubMed:29447282, PubMed:29659627, PubMed:30559377). According to some reports, YTHDF2 promotes viral gene expression and replication of polyomavirus SV40 and herpesvirus (KSHV) by binding to N6-methyladenosine (m6A)-containing viral RNAs (PubMed:29447282, PubMed:29659627). Another report however suggests that YTHDF2 regulates virus expression and replication indirectly, via its ability to inhibit the type I interferon response, thereby promoting virus expression (PubMed:30559377). Indirect regulation via inhibition of type I interferon response might explain why contradictory results have been reported for its role in KSHV virus replication (PubMed:29109479, PubMed:29659627). Previous studies suggested the 3 different paralogs (YTHDF1, YTHDF2 and YTHDF3) have unique functions with limited redundancy (PubMed:26046440). However, later studies showed that YTHDF1, YTHDF2 and YTHDF3 paralogs have redundant functions to a profound extent and directly promote degradation of m6A-containing mRNAs (PubMed:32492408). On the benefits of disorder - Issue 238 of August 2021