Figure 1 A proposed working model for NTM1 function. The membrane-bound form is proteolytically released by RIP, and the transcriptionally active form is translocated into the nucleus. The NTM1 proteins are stabilized by cytokinins. NTM1 processing and/or NTM1 expression would be induced by environmental stresses. Ub, ubiquitin, mNTM1 and nNTM1, membrane-bound and nuclear forms of NTM1, respectively.