P-element-induced wimpy testis-interacting RNA: A biomarker for gastric cancer diagnosis, progression, and prognosis

Figure 2 P-element-induced wimpy testis-interacting RNA biological functions. A: Transcriptional gene silencing (TGS): P-element-induced wimpy testis (PIWI)-initiated signals recruit regulatory factors to nucleosomal chromatin, thereby driving chromatin condensation into heterochromatin and repressing gene transcription; B: Post-transcriptional gene silencing (PTGS): PIWI proteins associate with mRNA molecules (spanning 5'UTR, exons, intron, and 3'UTR regions), and coordinate with modifications to inhibit gene expression at the post-transcriptional stage (via translational repression or mRNA degradation); C: PIWI-protein interactions: PIWI proteins engage in protein–protein interactions with protein 1 and protein 2 through their structural motifs; this process supports their regulatory functions in both TGS and PTGS. PiRNA: P-element-induced wimpy testis-interacting RNA; PIWI: P-element-induced wimpy testis; UTR: Untranslated region; DNMT: DNA methyltransferases.