title: U-richness is a defining feature of plant introns and may function as an intron recognition signal in maize.
abstract: Using a large set of plant gene sequences we compared individual introns to their flanking exons. Both Zea mays and Arabidopsis thaliana introns are U-rich but display no apparent bias for A. We identified fifteen 11-mer U-rich motifs as frequent elements of maize introns, and these are virtually absent from exons. By mutagenesis, we show that the single U-rich motif in the Bronze2 intron of maize plays a key role in intron processing in vivo.
authors.affiliation: Department of Biologìcal Sciences, Stanford University, CA 94305-5020, USA.
authors.forename: C H
authors.initials: CH
authors.lastname: Ko
authors.forename: V
authors.initials: V
authors.lastname: Brendel
authors.forename: R D
authors.initials: RD
authors.lastname: Taylor
authors.forename: V
authors.initials: V
authors.lastname: Walbot
mesh_terms: D001482:Base Composition; D005091:Exons; D007438:Introns; D012326:RNA Splicing; D017422:Sequence Analysis, DNA; D018271:Signal Recognition Particle / Q000235:genetics*; D014529:Uridine / Q000235:genetics*; D003313:Zea mays / Q000235:genetics*
chemical_list: D018271:Signal Recognition Particle; D014529:Uridine