Responsive Proteins To Mn Toxicity in Hippophae rhamnoides L.

Hippophae rhamnoides L. is uniquely capable of growing well under extreme environmental conditions. In this study, analysis of manganese (Mn) stress-responsive proteins in H. rhamnoides was conducted wherein greenhouse-grown seedlings were subjected to high Mn stress. Using by proteomic techniques, proteins, extracted from leaves, were analyzed using 2-dimensional electrophoresis (2-DE) and MALDI-TOF MS. Altogether, 55 proteins exhibited changes in abundance under stress. Of these, 13 proteins were identified, including three that disappeared under Mn (a putative ABC transporter ATP-binging protein, a heat shock protein Hslu, and a hypothetical protein XP-515578), seven that were up-regulated (three large subunits of rubisco, a hypothetical protein DSM3645-23351, a putative acyl-CoA dehydrogenase, a nesprin-2, and a J-type co-chaperone HSC20) and three that were only detected under Mn stress (a probable nitrogen regulation protein (NtrX), a 4-hydroxyphenylpyruvate dioxygenase, and an unnamed protein product). These proteins may function in beta-oxidation pathways in mitochondria, across membranes transport, abnormal protein removal or prevent protein aggregation arrest, cell division, cytoskeleton stabilization, iron-sulfur cluster assembly and antioxidant substance biosynthesis.