Roles of Membrane Traffic in C/N Regulation in terms of Ubiquitin Ligase ATL31

Abstract

In higher plants, metabolism of sugar (C) and nitrogen (N) is mutually regulated. To clarify the C/N regulator, we isolated novel C/N regulatory ubiquitin ligase ATL31 (Sato et al. Plant J, 60: 852, 2009). Plants overexpressing ATL31 showed insensitivity to C/N stress conditions, whereas the knockout mutants did the hypersensitivity.
To investigate the detailed functions of ATL31, we performed identification analysis of the ATL31-interacting proteins. Thus, 14-3-3s were found as the candidate for substrates of ubiquitination by ATL31. From further exploring ATL31-interacting proteins with cross-linker (DSP), we also identified the membrane traffic-related proteins.
Relationships between C/N balance regulation and membrane traffic will be discussed in terms of functions of ATL31.