Fig. 4: LncRNAs are indirectly involved in the regulation of AS.
From: Long non-coding RNAs are involved in alternative splicing and promote cancer progression
a PKM pre-mRNA can produce both PKM1 and PKM2 isoforms. HOXB-AS3 encodes a small peptide that competitively binds to the splicing factor hnRNPA1, thereby promoting the formation of PKM1 and ultimately inhibiting tumour growth. b Sp4 pre-mRNA can produce both long variants (Sp4-L) and short variants (Sp4-S) by AS. By interacting with SRSF3, the small peptide encoded by LOC90024 promotes the inclusion of exon 3 of Sp4 pre-mRNA and the generation of Sp4-L, which is conducive to tumour development. c TPM1-AS prevents the splicing effect of RBM4 on TPM1 by binding with the splicing factor RBM4, induces the generation of the TPM1 V1/V3/V4/V5 variant and inhibits the occurrence and development of tumour cells. d Mcl-1 pre-mRNA generates Mcl-1S (pro-apoptotic) and Mcl-1L (anti-apoptotic) by AS. The interaction between DGCR5 and SRSF1 promotes the retention of exon 2 and the generation of Mcl-1L. e MALAT1 hijacks SFPQ in the SFPQ/PTBP2 splicing factor complex, thereby causing the release of PTBP2 to promote tumour growth. Meanwhile, MALAT1 can control the transport and distribution of SR family proteins at transcription sites and among nuclear spots by affecting the phosphorylation of SR family proteins. MALAT1 forms a splicing complex with ID4, mut-P53 and SRSF1 to promote the distal 5′ splice‐site selection of exon 8, promoting the generation of angiogenic isoform VEGFAxxx (the subscript ××× indicates the number of amino acids in different isoforms).
