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

• DOI: 10.1261/rna.068221.118
• Publication Date: 2018-09-25T15:55:21Z
• Authors: Karen Doggett; Ben B. Williams; Sebastian Markmiller; Fan-Suo Geng; Janine Coates; Stephen Mieruszynski; Matthias Ernst; Tim Thomas; Joan K. Heath
• Keywords: Spliceosome; Conditional gene knockout

Splicing is an essential step in eukaryotic gene expression. While the majority of introns excised by U2-dependent, or major class, spliceosome, appropriate expression a very small subset genes depends on U12-dependent, minor splicing. The U11/U12 65K protein (hereafter 65K), encoded RNPC3 , one seven proteins that are unique to U12-dependent and previous studies including our own have established it plays role plant vertebrate development. To pinpoint impact loss during mammalian development adulthood, we generated germline conditional Rnpc3 -deficient mice. Homozygous −/− embryos died prior blastocyst implantation, whereas +/− mice were born at expected frequency, achieved sexual maturity, exhibited completely normal lifespan. Systemic recombination alleles adult ( lox/lox ) caused rapid weight loss, leukopenia, degeneration epithelial lining entire gastrointestinal tract, latter due increased cell death reduction proliferation. Accompanying this, observed both pro-proliferative phospho-ERK1/2 from stem/progenitor cells base intestinal crypts. RT-PCR analysis RNA extracted purified preparations with recombined lox revealed frequency U12-type intron retention all transcripts tested. Our study, using novel mouse model deficiency, establishes splicing not only important but indispensable throughout life.