Molecular analysis of somatic embryogenesis through proteomic approach and optimization of protocol in recalcitrant Musa spp.

Abstract

Somatic embryogenesis (SE) is a complex stress related process regulated by numerous biological factors. SE is mainly applicable to mass propagation and genetic improvement of plants through gene transfer technology and induced mutations. In banana, SE is highly genome dependent as the efficiency varies with cultivars. To understand the molecular mechanism of SE, a proteomics approach was carried out to identify proteins expressed during embryogenic calli (EC) induction, regeneration and germination of somatic embryos in the banana cultivar cv. Rasthali (AAB). In total, 70 spots were differentially expressed in various developmental stages of SE, of which 16 were uniquely expressed and 17 were highly abundant in EC compared to non‐embryogenic calli and explants. Also, four spots were uniquely expressed in germinating somatic embryos. The functional annotation of identified proteins revealed that calcium signaling along with stress and endogenous hormones related proteins played a vital role in EC induction and germination of somatic embryos. Thus, based on this outcome, the callus induction media was modified and tested in five cultivars. Among them, cultivars Grand Naine (AAA), Monthan (ABB) and Ney Poovan (AB) showed a better response in tryptophan added media, whereas Red Banana (AAA) and Karpuravalli (ABB) showed maximum EC induction in kinetin and CaCl2 supplemented media respectively. Simultaneously, germination media were modified to induce proteins responsible for germination. In cv. Rasthali, media supplemented with 10 mM CaCl2 showed a maximum increase in germination (51.79%) over control plants. Thus, the present study revealed that media modification based on proteomic analysis can induce SE in recalcitrant cultivars and also enhance germination in cultivars amenable for SE.

Full-Length Transcriptome Analysis of the ABCB, PIN/PIN-LIKES, and AUX/LAX Families Involved in Somatic Embryogenesis of Lilium pumilum DC. Fisch.

“…Pedroso and Pais reported that a high level of inorganic elements (Ca, K, Na, Mg, S, P and Fe) might be related to embryonic development or morphogenesis in Camellia japonica [71][72][73]. The calcium signaling pathway combined with stress and endogenous hormone-related proteins plays an important role in somatic embryo induction and germination, and the addition of CaCl 2 can promote callus induction and somatic embryo germination in banana [74]. Our results showed that the absence of one of the four groups of elements had a negative effect on SE and that macroelements were the most important.…”

“…Plant regeneration via SE is highly genotype dependent [74,77]. Moreover, the growth state of each explant is divergent, thus, the phenotype can be different under the same external environment.…”

Improvement of a Genetic Transformation System and Preliminary Study on the Function of LpABCB21 and LpPILS7 Based on Somatic Embryogenesis in Lilium pumilum DC. Fisch

“…Recent studies have shown that CaCl 2 (calcium chloride) can promote the induction of embryogenic calli (EC) and the germination of somatic embryos. Addition of 10 mM CaCl 2 increased the germination rate of somatic embryos by 51.79% [ 49 ]. The results of the present study indicate that an increase in the content of CaCl 2 from 0.44 g/L to 1.32 g/L can improve the germination coefficient of somatic embryos.…”

A step closer toward making many from the one

“…To understand the proteomic changes associated with SE in banana, Marimuthu et al () chose to work on cv. Rasthali, a popular Asian cultivar.…”

“…In the absence of any effective chemical control for this fungal infection, preserving the germplasm of popular banana cultivars and genetic modifications to generate disease‐resistant plants (Dale et al ) are the strategies that can save the banana from extinction. Efficient regeneration and SE will be extremely crucial in this effort, and the study by Marimuthu et al () will be a valuable resource for researchers working toward saving the banana.…”