The conserved splicing factor SUA controls alternative splicing of the developmental regulator ABI3 in Arabidopsis.
ABSCISIC ACID INSENSITIVE3 (ABI3) is a major regulator of seed maturation in Arabidopsis thaliana. We detected two ABI3 transcripts, ABI3-alpha and ABI3-beta, which encode full-length and truncated proteins, respectively. Alternative splicing of ABI3 is developmentally regulated, and the ABI3-beta transcript accumulates at the end of seed maturation. The two ABI3 transcripts differ by the presence of a cryptic intron in ABI3-alpha, which is spliced out in ABI3-beta. The suppressor of abi3-5 (sua) mutant consistently restores wild-type seed features in the frameshift mutant abi3-5 but does not suppress other abi3 mutant alleles. SUA is a conserved splicing factor, homologous to the human protein RBM5, and reduces splicing of the cryptic ABI3 intron, leading to a decrease in ABI3-beta transcript. In the abi3-5 mutant, ABI3-beta codes for a functional ABI3 protein due to frameshift restoration.
Sugliani
Matteo
M
Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, 50829 Cologne, Germany. sugliani@mpipz.mpg.de
Brambilla
Vittoria
V
Clerkx
Emile J M
EJ
Koornneef
Maarten
M
Soppe
Wim J J
WJ
D017398:Alternative Splicing; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002874:Chromosome Mapping; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018525:Germination; D007438:Introns; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D018749:RNA, Plant / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors
C091601:ABI3 protein, Arabidopsis; D029681:Arabidopsis Proteins; D018749:RNA, Plant; D016601:RNA-Binding Proteins; D014157:Transcription Factors