Heterosis - Molecular Bases of Heterosis

Molecular Bases of Heterosis

Molecular bases of heterosis remain a mystery so far, although this particular topic has gained a momentum in the plant scientist community. Most of the research concentrated upon the trancriptome, proteome and metabolome profiling of various developmental stages have shown that all possible mode of gene actions contribute to heterosis although to different extent in different hybrid. This include over dominance, dominance and additive modes. Further it has been shown that the regulatory measure operating behind these kind of changes are up to some extent epigenetic in nature. It has been reported that the clock/circadian rhythm components are involve and the major loop including CCA1/LHY genes and TOC1 genes are involve as master regulators. Variation in methylation hallmark exist between the two parents which are crossed and when these two different hall marks come together, they exerts a cumulative effect on the phenotype of the heterotic progeny. This observation also suggests that why not all crossed are heterotic in nature. However, studying are still in their nascent stage as the mechanism has not been reported in many circumstances. It has been found that in general, the photosynthetic ability, the protein synthesis ability etc are several fold higher in hybrid with respect to ether of the parents.