PTB2 RNA motif
The PTB2 RNA motif is a conserved intronic RNA element identified in plant homologs of the polypyrimidine tract-binding protein 2 (PTB2) gene that has been reported as a cis-regulatory element.[1]
Structure
PTB2 is an RNA motif reported as a stem-loop structure, with the loop containing a conserved GUGUGU sequence that encompasses the 5′ splice site of a cassette exon[2] involved in alternative splicing. The 3' side of the stem contains a long conserved pyrimidine-rich tract.
Distribution
The PTB2 RNA motif was identified in homologous of 93 species of Pentapetalae plants.[1]
Function
The long conserved pyrimidine-rich tract located on the 3′ side of the PTB2 RNA motif stem suggests a role in regulation of PTB2 genes. The co-occurrence of the PTB2 RNA motif and PTB2 genes is consistent with a mechanistic link between RNA secondary structure and PTB-mediated splicing regulation. The motif has been proposed to contribute to regulation of PTB2 expression by influencing PTB1/PTB2 binding and promoting cassette exon inclusion during alternative splicing, which can lead to nonsense-mediated decay of the resulting transcript.[1]
References
- 1 2 3 Sack, Maximilian; Reinhardt, Maren; Burgardt, Rica; Berg, Philipp; Bauer, Julia; Wachter, Andreas; Weinberg, Zasha (2025). "Identification and characterization of new structured RNA classes in plants". RNA Biology. 22 (1): 1–16. doi:10.1080/15476286.2025.2523696. ISSN 1555-8584. PMC 12218528. PMID 40587820.
- ↑ Burgardt, Rica; Lambert, Dorothee; Heuwieser, Christina; Sack, Maximilian; Wagner, Gabriele; Weinberg, Zasha; Wachter, Andreas (2024). "Positioning of pyrimidine motifs around cassette exons defines their PTB-dependent splicing in Arabidopsis". The Plant Journal: For Cell and Molecular Biology. 118 (6): 2202–2218. doi:10.1111/tpj.16739. ISSN 1365-313X. PMID 38578875.