MoHTR1, a Nuclear Effector of the Rice Blast Fungus, Regulates Alternative Splicing of Rice Immunity Genes

Area of Science:

• Plant pathology
• Molecular biology
• Genetics

Background:

• Plant pathogens use nuclear effectors to manipulate host immunity.
• Alternative splicing is crucial for regulating immune response genes.
• Understanding how single effectors control multiple nuclear processes is limited.

Purpose of the Study:

• Investigate the multifunctionality of MoHTR1, a nuclear effector from the rice blast fungus.
• Identify host proteins interacting with MoHTR1.
• Elucidate MoHTR1's role in regulating host gene expression and immunity.

Main Methods:

• Protein-protein interaction assays to identify MoHTR1 interactors.
• Analysis of MoHTR1's effect on splicing factor OsSR45.
• RNA sequencing to assess alternative splicing changes in target genes.
• Comparison of splicing patterns in infected rice and MoHTR1-overexpressing plants.

Main Results:

• MoHTR1 interacts with rice splicing factor OsSR45 and promotes its degradation.
• MoHTR1 influences alternative splicing of mRNAs involved in immune and stress responses.
• Observed alternative splicing changes are consistent in infected and transgenic rice, confirming MoHTR1's regulatory role.

Conclusions:

• MoHTR1 exhibits dual regulatory roles, affecting both transcription and posttranscriptional processing (alternative splicing).
• This study provides new insights into nuclear effector strategies for modulating host immunity.
• MoHTR1's interaction with OsSR45 is a key mechanism for manipulating host responses.