ZmSKIP enhances drought tolerance by reducing stomatal aperture in maize

Area of Science:

• Plant molecular biology
• Plant stress physiology

Background:

• Ski-interacting proteins (SKIPs) regulate gene expression post-transcriptionally during plant stress responses.
• The role of SKIPs in transcriptional regulation of drought stress tolerance, especially in maize, remains largely unexplored.

Purpose of the Study:

• To investigate the function of ZmSKIP in regulating drought tolerance at the transcriptional level in maize.
• To elucidate the molecular mechanism by which ZmSKIP enhances drought tolerance.

Main Methods:

• Generation and analysis of ZmSKIP overexpression and skip-aa mutant transgenic maize plants.
• Identification of ZmSKIP direct binding targets using DNA motif analysis.
• Investigation of ZmBAG8 function and its interaction with ZmSKIP under drought stress.
• Analysis of ZmSKIP phosphorylation by ZmSnRK2.3 and its effect on ZmBAG8 expression.

Main Results:

• Overexpression of ZmSKIP enhanced drought tolerance through stomatal closure and reduced water loss.
• ZmSKIP directly binds to the promoter of ZmBAG8, a negative regulator of drought tolerance.
• ZmSnRK2.3 phosphorylates ZmSKIP, strengthening its ability to suppress ZmBAG8 expression and improve drought tolerance.

Conclusions:

• ZmSKIP plays a crucial role in enhancing maize drought tolerance.
• ZmSnRK2.3-mediated phosphorylation of ZmSKIP is a key regulatory mechanism that suppresses ZmBAG8 expression, leading to reduced stomatal aperture and improved drought resistance.