RT Journal Article
SR Electronic
T1 The Arabidopsis R-SNARE VAMP714 is essential for polarization of PIN proteins in the establishment and maintenance of auxin gradients
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 821272
DO 10.1101/821272
A1 Xiaoyan Gu
A1 Kumari Fonseka
A1 Stuart A. Casson
A1 Andrei Smertenko
A1 Guangqin Guo
A1 Jennifer F. Topping
A1 Patrick J. Hussey
A1 Keith Lindsey
YR 2020
UL http://biorxiv.org/content/early/2020/06/06/821272.abstract
AB The plant hormone auxin and its directional intercellular transport plays a major role in diverse aspects of plant growth and development. The establishment of auxin gradients in plants requires asymmetric distribution of members of the auxin efflux carrier PIN-FORMED (PIN) protein family to the plasma membrane. An endocytic pathway regulates the recycling of PIN proteins between the plasma membrane and endosomes, providing a mechanism for dynamic localization.N-ethylmaleimide-sensitive factor adaptor protein receptors (SNAP receptors, SNAREs) mediate fusion between vesicles and target membranes and are classed as Q- or R-SNAREs based on their sequence. We analysed gain- and loss-of-function mutants, dominant negative transgenics and protein localization of the Arabidopsis R-SNARE VAMP714 to understand its function.We demonstrate that VAMP714 is essential for the insertion of PINs into the plasmamembrane, for polar auxin transport, and for root gravitropism and morphogenesis. VAMP714 gene expression is upregulated by auxin, and the VAMP714 protein co-localizes with ER and Golgi vesicles and with PIN proteins at the plasma membrane.It is proposed that VAMP714 mediates the delivery of PIN-carrying vesicles to the plasma membrane, and that this forms part of a positive regulatory loop in which auxin activates a VAMP714-dependent PIN/auxin transport system to control development.Competing Interest StatementThe authors have declared no competing interest.