Embryogenic Competence Acquisition in Sugar Cane Callus Is Associated with Differential W-Pump Abundance and Activity

作者：Passamani Lucas Z; Bertolaz Amanda A; Ramos Alessandro C; Santa Catarina Claudete; Thelen Jay J; Silveira Vanildo^*

来源：Journal of Proteome Research, 2018, 17(8): 2767-2779.

DOI：10.1021/acs.jproteome.8b00213

• somatic embryogenesis
• ion-selective vibrating probe
• Saccharum spp.
• H+ pumps
• microsomal proteomics

Somatic embryogenesis is an important biological process in several plant species, including sugar cane. Proteomics approaches have shown that H+ pumps are differentially regulated during somatic embryogenesis; however, the relationship between H+ flux and embryogenic competence is still unclear. This work aimed to elucidate the association between extracellular H+ flux and somatic embryo maturation in sugar cane. We performed a microsomal proteomics analysis and analyzed changes in extracellular H+-flux and H+-pump (P-H(+)ATPase, V-H+-ATPase, and H+-PPase) activity in embryogenic and non-embryogenic callus. A total of 657 proteins were identified, 16 of which were H+ pumps. We observed that P-H+-ATPase and H+-PPase were more abundant in embryogenic callus. Compared to non-embryogenic callus, embryogenic callus showed higher H+ influx, especially on maturation day 14, as well as higher H+-pump activity (mainly, P-H(+)ATPase and H+-PPase activity). H+-PPase appears to be the major H+ pump in embryogenic callus during somatic embryo formation, functioning in both vacuole acidification and PPi homeostasis. These results provide evidence for an association between higher H+-pump protein abundance and, consequently, higher H+ flux and embryogenic competence acquisition in the callus of sugar cane, allowing for the optimization of the somatic embryo conversion process by modulating the activities of these H+ pumps.

• 出版日期2018-8