Specifically recognizes and binds N6-methyladenosine (m6A)-containing mRNAs, and regulates their stability (PubMed:24284625, PubMed:32492408, PubMed:26318451). 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:24284625, PubMed:32492408). Acts as a regulator of mRNA stability by promoting degradation of m6A-containing mRNAs via interaction with the CCR4-NOT complex (PubMed:32492408). The YTHDF paralogs (YTHDF1, YTHDF2 and YTHDF3) shares m6A-containing mRNAs targets and act redundantly to mediate mRNA degradation and cellular differentiation (PubMed:28106072, PubMed:32492408). Required to facilitate learning and memory formation in the hippocampus by binding to m6A-containing neuronal mRNAs (By similarity). Acts as a regulator of axon guidance by binding to m6A-containing ROBO3 transcripts (By similarity). Acts as a negative regulator of antigen cross-presentation in myeloid dendritic cells (By similarity). In the context of tumorigenesis, negative regulation of antigen cross-presentation limits the anti-tumor response by reducing efficiency of tumor-antigen cross-presentation (By similarity). 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). 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). Interacts with CNOT1; promoting recruitment of the CCR4-NOT complex (PubMed:32492408). Interacts with ribosomes (PubMed:26046440). Interacts with eIF3 (EIF3A or EIF3B) (PubMed:26046440). Interacts with YTHDF3 (PubMed:28106072). 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). Belongs to the YTHDF family. YTHDF1 subfamily. Was initially reported to act as a regulator of mRNA translation efficiency by promoting ribosome loading to m6A-containing mRNAs and by interacting with translation initiation factors eIF3 (EIF3A or EIF3B), thereby facilitating translation initiation (PubMed:26046440, PubMed:26593424). These studies suggested that the 3 different paralogs (YTHDF1, YTHDF2 and YTHDF3) have unique functions with limited redundancy (PubMed:26046440, PubMed:26593424). 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). The effect on translation efficiency observed earlier is probably indirect (PubMed:32492408). On the benefits of disorder - Issue 238 of August 2021