CBL-Interacting Protein Kinase OsCIPK18 Regulates the Response of Ammonium Toxicity in Rice Roots

CBL-Interacting Protein Kinase OsCIPK18 Regulates the Response of Ammonium Toxicity in Rice Roots

Blog Article

Ammonium (NH4+) is one of the major nitrogen sources for plants.However, excessive ammonium can cause serious harm to the growth and development of plants, i.e.

, ammonium toxicity.The primary regulatory mechanisms behind ammonium toxicity are still poorly characterized.In this study, we showed that OsCIPK18, a CBL-interacting protein kinase, plays an important role in response to ammonium toxicity by comparative analysis of the physiological and whole transcriptome of the T-DNA insertion mutant (cipk18) and the wild-type (WT).

Root biomass and length of cipk18 are less inhibited by excess NH4+ compared with WT, indicating increased resistance to ammonium toxicity.Transcriptome analysis reveals fire resistant tablecloth that OsCIPK18 affects the NH4+ uptake by regulating the expression of OsAMT1;2 and other NH4+ transporters, but does not affect ammonium candy button strips assimilation.Differentially expressed genes induced by excess NH4+ in WT and cipk18 were associated with functions, such as ion transport, metabolism, cell wall formation, and phytohormones signaling, suggesting a fundamental role for OsCIPK18 in ammonium toxicity.

We further identified a transcriptional regulatory network downstream of OsCIPK18 under NH4+ stress that is centered on several core transcription factors.Moreover, OsCIPK18 might function as a transmitter in the auxin and abscisic acid (ABA) signaling pathways affected by excess ammonium.These data allowed us to define an OsCIPK18-regulated/dependent transcriptomic network for the response of ammonium toxicity and provide new insights into the mechanisms underlying ammonium toxicity.