| First Author | Doggett K | Year | 2018 |
| Journal | RNA | Volume | 24 |
| Issue | 12 | Pages | 1856-1870 |
| PubMed ID | 30254136 | Mgi Jnum | J:267519 |
| Mgi Id | MGI:6268206 | Doi | 10.1261/rna.068221.118 |
| Citation | Doggett K, et al. (2018) Early developmental arrest and impaired gastrointestinal homeostasis in U12-dependent splicing-defective Rnpc3-deficient mice. RNA 24(12):1856-1870 |
| abstractText | 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 pinpoint 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 (Rnpc3 (lox/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 Rnpc3 (lox) 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. |
