title: Plant SMU-1 and SMU-2 homologues regulate pre-mRNA splicing and multiple aspects of development.
abstract: In eukaryotes, alternative splicing of pre-mRNAs contributes significantly to the proper expression of the genome. However, the functions of many auxiliary spliceosomal proteins are still unknown. Here, we functionally characterized plant homologues of nematode suppressors of mec-8 and unc-52 (smu). We compared transcript profiles of maize (Zea mays) smu2 endosperm with those of wild-type plants and identified pre-mRNA splicing events that depend on the maize SMU2 protein. Consistent with a conserved role of plant SMU-2 homologues, Arabidopsis (Arabidopsis thaliana) smu2 mutants also show altered splicing of similar target pre-mRNAs. The Atsmu2 mutants occasionally show developmental phenotypes, including abnormal cotyledon numbers and higher seed weights. We identified AtSMU1 as one of the SMU2-interacting proteins, and Atsmu1 mutations cause similar developmental phenotypes with higher penetrance than Atsmu2. The AtSMU2 and AtSMU1 proteins are localized to the nucleus and highly prevalent in actively dividing tissues. Taken together, our data indicated that the plant SMU-1 and SMU-2 homologues appear to be involved in splicing of specific pre-mRNAs that affect multiple aspects of development.
authors.affiliation: Department of Plant Sciences, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: Taijoon
authors.initials: T
authors.lastname: Chung
authors.forename: Dongfang
authors.initials: D
authors.lastname: Wang
authors.forename: Cheol-Soo
authors.initials: CS
authors.lastname: Kim
authors.forename: Ramin
authors.initials: R
authors.lastname: Yadegari
authors.forename: Brian A
authors.initials: BA
authors.lastname: Larkins
mesh_terms: D017398:Alternative Splicing; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D016254:Mutagenesis, Insertional; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D025941:Protein Interaction Mapping; D012322:RNA Precursors / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D010940:Plant Proteins; D012322:RNA Precursors; D018749:RNA, Plant; D011994:Recombinant Proteins; C036483:T-DNA