RESUMEN

Alternative splicing is prevalent in plants, but little is known about its regulation in the context of developmental and signaling pathways. We describe here a new factor that influences pre-messengerRNA (mRNA) splicing and is essential for embryonic development in Arabidopsis thaliana. This factor was retrieved in a genetic screen that identified mutants impaired in expression of an alternatively spliced GFP reporter gene. In addition to the known spliceosomal component PRP8, the screen recovered Arabidopsis RTF2 (AtRTF2), a previously uncharacterized, evolutionarily conserved protein containing a replication termination factor 2 (Rtf2) domain. A homozygous null mutation in AtRTF2 is embryo lethal, indicating that AtRTF2 is an essential protein. Quantitative RT-PCR demonstrated that impaired expression of GFP in atrtf2 and prp8 mutants is due to inefficient splicing of the GFP pre-mRNA. A genome-wide analysis using RNA sequencing indicated that 13-16% of total introns are retained to a significant degree in atrtf2 mutants. Considering these results and previous suggestions that Rtf2 represents an ubiquitin-related domain, we discuss the possible role of AtRTF2 in ubiquitin-based regulation of pre-mRNA splicing.

Asunto(s)

Empalme Alternativo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Dominios y Motivos de Interacción de Proteínas , Precursores del ARN/genética , Oxidorreductasas de Alcohol/química , Oxidorreductasas de Alcohol/genética , Oxidorreductasas de Alcohol/metabolismo , Secuencia de Aminoácidos , Proteínas de Arabidopsis/química , Expresión Génica , Orden Génico , Genes Reporteros , Prueba de Complementación Genética , Sitios Genéticos , Genotipo , Datos de Secuencia Molecular , Mutación , Fenotipo , Plantas Modificadas Genéticamente , Unión Proteica , Alineación de Secuencia , Empalmosomas/metabolismo