In:
RNA, Cold Spring Harbor Laboratory, Vol. 23, No. 1 ( 2017-01), p. 47-57
Abstract:
Spliceostatin A (SSA) is a methyl ketal derivative of FR901464, a potent antitumor compound isolated from a culture broth of Pseudomonas sp . no. 2663. These compounds selectively bind to the essential spliceosome component SF3b, a subcomplex of the U2 snRNP, to inhibit pre-mRNA splicing. However, the mechanism of SSA's antitumor activity is unknown. It is noteworthy that SSA causes accumulation of a truncated form of the CDK inhibitor protein p27 translated from CDKN1B pre-mRNA, which is involved in SSA-induced cell-cycle arrest. However, it is still unclear whether pre-mRNAs are uniformly exported from the nucleus following SSA treatment. We performed RNA-seq analysis on nuclear and cytoplasmic fractions of SSA-treated cells. Our statistical analyses showed that intron retention is the major consequence of SSA treatment, and a small number of intron-containing pre-mRNAs leak into the cytoplasm. Using a series of reporter plasmids to investigate the roles of intronic sequences in the pre-mRNA leakage, we showed that the strength of the 5′ splice site affects pre-mRNA leakage. Additionally, we found that the level of pre-mRNA leakage is related to transcript length. These results suggest that the strength of the 5′ splice site and the length of the transcripts are determinants of the pre-mRNA leakage induced by SF3b inhibitors.
Type of Medium:
Online Resource
ISSN:
1355-8382
,
1469-9001
DOI:
10.1261/rna.058065.116
Language:
English
Publisher:
Cold Spring Harbor Laboratory
Publication Date:
2017
detail.hit.zdb_id:
1475737-0
SSG:
12