Skip to main content
Log in

Phosphorylation by Prp4 kinase releases the self-inhibition of FgPrp31 in Fusarium graminearum

  • Original Article
  • Published:
Current Genetics Aims and scope Submit manuscript

Abstract

Prp31 is one of the key tri-snRNP components essential for pre-mRNA splicing although its exact molecular function is not well studied. In a previous study, suppressor mutations were identified in the PRP31 ortholog in two spontaneous suppressors of Fgprp4 mutant deleted of the only kinase of the spliceosome in Fusarium graminearum. To further characterize the function of FgPrp31 and its relationship with FgPrp4 kinase, in this study we identified additional suppressor mutations in FgPrp31 and determined the suppressive effects of selected mutations. In total, 28 of the 35 suppressors had missense or nonsense mutations in the C terminus 465–594 aa (CT130) region of FgPrp31. The other 7 had missense or deletion mutations in the 7–64 aa region. The nonsense mutation at R464 in FgPRP31 resulted in the truncation of CT130 that contains all the putative Prp4 kinase-phosphorylation sites reported in humans, and partially rescued intron splicing defects of Fgprp4. The CT130 of FgPrp31 displayed self-inhibitory interaction with the N-terminal 1-463 (N463) region, which was reduced or abolished by the L532P, D534G, or G529D mutation in yeast two-hybrid assays. The N463 region, but not full-length FgPrp31, interacted with the N-terminal region of FgBrr2, one main U5 snRNP protein. The L532P mutation in FgPrp31 increased its interaction with FgBrr2. In contrast, suppressor mutations in FgPrp31 reduced its interaction with FgPrp6, another key component of tri-snRNP. Furthermore, we showed that FgPrp31 was phosphorylated by FgPrp4 in vivo. Site-directed mutagenesis analysis showed that phosphorylation at multiple sites in FgPrp31 is necessary to suppress Fgprp4, and S520 and S521 are important FgPrp4-phosphorylation sites. Overall, these results indicated that phosphorylation by FgPrp4 at multiple sites may release the self-inhibitory binding of FgPrp31 and affect its interaction with other components of tri-snRNP during spliceosome activation.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others

References

Download references

Acknowledgements

We thank Drs. Chenfang Wang, Cong Jiang, Huiquan Liu, and Anton Iliuk for fruitful discussions. We also thank Dr. Yimei Zhang and Ms. Xiaoping Li for assistance with the yeast two-hybrid and co-IP assays. This work was supported by Grants from the Nature Science Foundation of China (31600117), US Wheat and Barley Scab Initiative (106616), and Fundamental Research Funds for the Central Universities (2452016019).

Author information

Authors and Affiliations

Authors

Contributions

Conceived and designed the experiments: XG, QJ, JRX. Performed the experiments: XG, CS, JZ, KY, JW. Analyzed the data: XG, QJ, JRX. Contributed reagents/materials/analysis tools: XG, QJ. Wrote the paper: XG, QJ, JRX.

Corresponding authors

Correspondence to Qiaojun Jin or Jin-Rong Xu.

Additional information

Communicated by M. Kupiec.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOC 146 KB)

294_2018_838_MOESM2_ESM.jpg

Fig S1 Deletion of C-terminal 130 aa in FgPRP31 (a) The FgPRP31 gene, FgPRP31ΔCT130 replacement construct, and primers used. (b) Three-day-old PDA cultures (Top), two-week-old mating cultures (Middle), and plant infection assays on wheat coleoptile (Bottom) of the wild type (WT) and the FgPRP31ΔCT130 mutant strains (JPG 2882 KB)

294_2018_838_MOESM3_ESM.jpg

Fig S2 Yeast two-hybrid assays for the FgPrp31-FgBrr2 and FgPrp31-FgPrp6 interactions. Yeast transformants expressing the marked bait and prey constructs were assayed for growth on SD-Trp-Leu-His plates and LacZ activities. The positive and negative controls are from the Matchmaker kit (JPG 3328 KB)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Gao, X., Zhang, J., Song, C. et al. Phosphorylation by Prp4 kinase releases the self-inhibition of FgPrp31 in Fusarium graminearum. Curr Genet 64, 1261–1274 (2018). https://doi.org/10.1007/s00294-018-0838-4

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00294-018-0838-4

Keywords

Navigation