The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms
- 731 Downloads
The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms. These proteins also move rapidly and continuously in the nuclei, and their movements are affected by ATP depletion.
The U2AF65 proteins are splicing factors that interact with SF1 and U2AF35 proteins to promote U2snRNP for the recognition of the pre-mRNA 3′ splice site during early spliceosome assembly. We have determined the subcellular localization and movement of these proteins’ Arabidopsis homologs. It was found that Arabidopsis U2AF65 homologs, AtU2AF65a, and AtU2AF65b proteins interact with AtU2AF35a and AtU2AF35b, which are Arabidopsis U2AF35 homologs. We have examined the mobility of these proteins including AtSF1 using fluorescence recovery after photobleaching and fluorescence loss in photobleaching analyses. These proteins displayed dynamic movements in nuclei and their movements were affected by ATP depletion. We have also demonstrated that these proteins shuttle between nuclei and cytoplasms, suggesting that they may also function in cytoplasm. These results indicate that such splicing factors show very similar characteristics to their human counterparts, suggesting evolutionary conservation.
KeywordsDynamic movement FRAP FLIP SF1 Shuttling U2AF35 U2AF65
Fluorescence loss in photobleaching
Fluorescence recovery after photobleaching
Green fluorescence protein
Precursor messenger RNA
Splicing factor 1
Small nuclear ribonucleoproteins
U2 snRNP auxiliary splicing factor
Nuclear export signal
This work was supported by the Basic Science Research Program through the National Research Foundation of Korea, funded by the Ministry of Education (to J.-K. Kim), and by a Korea University Grant (to J.-K. Kim).
Compliance with ethical standards
Conflict of interest
The authors have no conflicts of interest to declare.
- Brandizzi F, Snapp EL, Roberts AG, Lippincott-Schwartz J, Hawes C (2002) Membrane protein transport between the endoplasmic reticulum and the Golgi in tobacco leaves is energy dependent but cytoskeleton independent: evidence from selective photobleaching. Plant Cell 14:1293–1309CrossRefPubMedPubMedCentralGoogle Scholar
- Burge CB, Tuschl T, Sharp PA (1999) Splicing of precursors to mRNAs by the spliceosome. In: Gesteland RF, Cech TR, Atkins JF (eds) The RNA world. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York, pp 525–560Google Scholar
- Koroleva OA, Clader G, Pendle AF, Kim SH, Lewandowska D, Simpson CG et al (2009) Dynamic behavior of Arabidopsis eIF4A-III, putative core protein of exon junction complex: fast relocation to nucleolus and splicing speckles under hypoxia. Plant Cell 21:1592–1606CrossRefPubMedPubMedCentralGoogle Scholar
- Weigel D, Glazebrook J (2002) Arabidopsis. A laboratory manual. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NYGoogle Scholar