Early developmental arrest and impaired gastrointestinal homeostasis in U12-dependent splicing-defective Rnpc3-deficient mice

Doggett, K; Williams, BB; Markmiller, S; Geng, FS; Coates, J; Mieruszynski, S; Ernst, M; Thomas, T; Heath, JK

Author(s): Doggett, K; Williams, BB; Markmiller, S; Geng, FS; Coates, J; Mieruszynski, S; Ernst, M; Thomas, T; Heath, JK;
Details: Publication Year 2018-12,Volume 24,Issue #12,Page 1856-1870
Journal Title: RNA
Publication Type: Journal Article
Abstract: Splicing is an essential step in eukaryotic gene expression. While the majority of introns is excised by the U2-dependent, or major class, spliceosome, the appropriate expression of a very small subset of genes depends on U12-dependent, or minor class, splicing. The U11/U12 65K protein (hereafter 65K), encoded by RNPC3, is one of seven proteins that are unique to the U12-dependent spliceosome, and previous studies, including our own, have established that it plays a role in plant and vertebrate development. To pin-point the impact of 65K loss during mammalian development and in adulthood, we generated germline and conditional Rnpc3-deficient mice. Homozygous Rnpc3-/- embryos died prior to blastocyst implantation, whereas Rnpc3+/- mice were born at the expected frequency, achieved sexual maturity and exhibited a completely normal lifespan. Systemic recombination of conditional Rnpc3 alleles in adult (Rnpc3lox/lox) mice caused rapid weight loss, leukopenia and degeneration of the epithelial lining of the entire gastrointestinal tract, the latter due to increased cell death and a reduction in cell proliferation. Accompanying this, we observed a loss of both 65K and the pro-proliferative phospho-ERK1/2 proteins from the stem/progenitor cells at the base of intestinal crypts. RT-PCR analysis of RNA extracted from purified preparations of intestinal epithelial cells with recombined Rnpc3lox alleles revealed increased frequency of U12-type intron retention in all transcripts tested. Our study, using a novel conditional mouse model of Rnpc3 deficiency, establishes that U12-dependent splicing is not only important during development but is indispensable throughout life.
Publisher: CSH Press
Research Division(s): Development And Cancer
PubMed ID: 30254136
Publisher's Version: https://doi.org/10.1261/rna.068221.118
Open Access at Publisher's Site: https://doi.org/10.1261/rna.068221.118
NHMRC Grants: NHMRC/1024878, NHMRC/1022870,
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 2018-10-11 04:23:14

Last Modified: 2018-12-05 02:57:29