Differential Proteomic Analysis of Germinating and Non-germinating Somatic Embryo of Banana cv. Grand Naine (AAA)

Abstract

Germination of somatic embryos (se) is an important event in a whole somatic embryogenesis (SE) process. Though the well matured somatic embryos of banana were placed on the germination medium with complete contact only 50% of the somatic embryos were germinated into plantlets having either shoots, roots or sometimes both. Hence in order to increase the germination efficacy it is essential to understand the molecular basis underlying the process of germination. In the present study, we have analyzed differential proteome expression between germinating somatic embryo (Gse) and non germinating somatic embryos (NGse) of cv. Grand Naine by using two dimensional gel electrophoresis followed by MALDI-TOF MS/MS analysis. In total 16 protein spots were differentially expressed between Gse and NGse in which 15 were successfully identified. In that, 14 spots were upregulated and 1 spot was downregulated in Gse than NGse. High accumulation of SAUR auxin responsive proteins and cold stress proteins like 3-ketoacyl-CoA synthase and Oleosin were highly expressed in Gse than NGse. Hence SAUR triggering factors like NAA, and GA3 were supplemented in the germination medium in three combinations along with cold treatments of 4°C at 0 hr, 12 hr and 24 hr. High germination efficiency of 93% was observed in 24 hr treated embryos in medium supplemented with 1mg/L NAA and 0.5 mg/L GA3.