Glucose inhibits root meristem growth via ABA INSENSITIVE 5, which represses PIN1 accumulation and auxin activity in Arabidopsis

Abstract

Glucose functions as a hormone-like signalling molecule that modulates plant growth and development in Arabidopsis thaliana. However, the role of glucose in root elongation remains elusive. Our study demonstrates that high concentrations of glucose reduce the size of the root meristem zone by repressing PIN1 accumulation and thereby reducing auxin levels. In addition, we verified the involvement of ABA INSENSITIVE 5 (ABI5) in this process by showing that abi5-1 is less sensitive to glucose than the wild type, whereas glucose induces ABI5 expression and the inducible overexpression of ABI5 reduces the size of the root meristem zone. Furthermore, the inducible overexpression of ABI5 in PIN1::PIN1-GFP plants reduces the level of PIN1-GFP, but glucose reduces the level of PIN1-GFP to a lesser extent in abi5-1 PIN1::PIN1-GFP plants than in the PIN1::PIN1-GFP control, suggesting that ABI5 is involved in glucoseregulated PIN1 accumulation. Taken together, our data suggest that ABI5 functions in the glucose-mediated inhibition of the root meristem zone by repressing PIN1 accumulation, thus leading to reduced auxin levels in roots.

Interaction between Glucose and Brassinosteroid during the Regulation of Lateral Root Development in Arabidopsis

“…The BR signaling pathway has been reported to influence the functions of auxin and vice versa during root growth and development (Nemhauser et al, 2004;Mouchel et al, 2006;Hardtke et al, 2007;Vert et al, 2008). Similarly, sugar signals are also reported to interact with the auxin signaling machinery (Moore et al, 2003;Gonzali et al, 2005;Ohto et al, 2006;Mishra et al, 2009;Mudgil et al, 2009;Booker et al, 2010;Sairanen et al, 2012;Yuan et al, 2014). Glc inhibits the G-protein complex-dependent Figure 10.…”

“…These and various other factors form a complex signal response network to bring about optimum growth changes to enable better fitness in plants. Glc and auxin can interact extensively to control many aspects of root architecture, such as root elongation, LR production, root hair development, and root directional growth (Mishra et al, 2009;Mudgil et al, 2009;Booker et al, 2010;Yuan et al, 2014). However, there are very few reports in the literature that either directly or indirectly link BR responses to sugar signaling (Laxmi et al, 2004;Rognoni et al, 2007;Gupta et al, 2012;Singh et al, 2014a).…”

“…Previous studies suggested a prominent effect of Glc on root growth and development in Arabidopsis (Mishra et al, 2009;Booker et al, 2010;Kircher and Schopfer, 2012;Xiong et al, 2013;Yuan et al, 2014). Increasing Figure 1.…”

Abscisic Acid Is a General Negative Regulator of Arabidopsis Axillary Bud Growth

“…Similarly, ABI5 was shown to repress PIN1 accumulation and auxin activity in Arabidopsis root tips in response to Glc (Yuan et al, 2014). Because ABI5 is also a component of the ABA-signaling pathway, it is possible that ABA effects are partially mediated by ABI5.…”

The Nitrification Inhibitor Methyl 3-(4-Hydroxyphenyl)Propionate Modulates Root Development by Interfering with Auxin Signaling via the NO/ROS Pathway

“…The above results show that PAT is required for the MHPP-induced inhibition of PR growth. PAT is mediated by auxin influx carriers in the AUX/LAX family and efflux carriers in the PIN family (Péret et al, 2012;Yuan et al, 2014;Yuan and Huang, 2016). Thus, we examined whether MHPP treatment also affects the expression of auxin carriers in roots.…”