Characterization of maize spermine synthase 1 (ZmSPMS1): Evidence for dimerization and intracellular location.
Polyamines are ubiquitous positively charged metabolites that play an important role in wide fundamental cellular processes; because of their importance, the homeostasis of these amines is tightly regulated. Spermine synthase catalyzes the formation of polyamine spermine, which is necessary for growth and development in higher eukaryotes. Previously, we reported a stress inducible spermine synthase 1 (ZmSPMS1) gene from maize. The ZmSPMS1 enzyme differs from their dicot orthologous by a C-terminal extension, which contains a degradation PEST sequence involved in its turnover. Herein, we demonstrate that ZmSPMS1 protein interacts with itself in split yeast two-hybrid (Y2H) assays. A Bimolecular Fluorescence Complementation (BiFC) assay revealed that ZmSPMS1 homodimer has a cytoplasmic localization. In order to gain a better understanding about ZmSPMS1 interaction, two deletion constructs of ZmSPMS1 protein were obtained. The ΔN-ZmSPMS1 version, where the first 74 N-terminal amino acids were eliminated, showed reduced capability of dimer formation, whereas the ΔC-ZmSPMS1 version, lacking the last 40 C-terminal residues, dramatically abated the ZmSPMS1-ZmSPMS1 protein interaction. Recombinant protein expression in Escherichia coli of ZmSPMS1 derived versions revealed that deletion of its N-terminal domain affected the spermine biosynthesis, whereas C-terminal ZmSPMS1 truncated version fail to generate this polyamine. These data suggest that N- and C-terminal domains of ZmSPMS1 play a role in a functional homodimer.
Laboratorio de Estudios Moleculares de Respuesta a Estrés en Plantas, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica AC, Camino a la Presa de San José 2055, C.P. 78216, AP 3-74 Tangamanga, San Luis Potosí, San Luis Potosí, Mexico.
Israel
I
Maruri-López
Laboratorio de Estudios Moleculares de Respuesta a Estrés en Plantas, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica AC, Camino a la Presa de San José 2055, C.P. 78216, AP 3-74 Tangamanga, San Luis Potosí, San Luis Potosí, Mexico.
Itzell E
IE
Hernández-Sánchez
Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Avda de los Naranjos s/n, 46022, Valencia, Spain.
Alejandro
A
Ferrando
Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-Consejo Superior de Investigaciones Científicas, Avda de los Naranjos s/n, 46022, Valencia, Spain.
Juan
J
Carbonell
Laboratorio de Estudios Moleculares de Respuesta a Estrés en Plantas, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica AC, Camino a la Presa de San José 2055, C.P. 78216, AP 3-74 Tangamanga, San Luis Potosí, San Luis Potosí, Mexico. Electronic address: jbremont@ipicyt.edu.mx.
Juan Francisco
JF
Jiménez-Bremont
D005453:Fluorescence; D042541:Intracellular Space / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D011073:Polyamines / Q000378:metabolism; D011485:Protein Binding; D055503:Protein Multimerization; D013097:Spermine Synthase / Q000378:metabolism*; D014026:Nicotiana / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D025801:Ubiquitin / Q000378:metabolism; D003313:Zea mays / Q000201:enzymology*
D011073:Polyamines; D025801:Ubiquitin; D013097:Spermine Synthase
Bimolecular fluorescence complementation; C-terminal; Homodimer; Spermine synthase; Spermine synthesis; Subcellular localization; Yeast two-hybrid