Genic Molecular Markers in Fungi: Availability and Utility for Bioprospection

Abstract

Fungi are the second most diverse group of organism after insects on the earth. While, there is huge morphological and biological diversity between different fungal taxon, nevertheless it is difficult to distinguish them within a single lowest rank of taxon or below that, due to their high morphological and biological similarity. The recent advancement in molecular biology and genomics helps in generation of vast amount of genetic data using various molecular markers that could be highly correlated with various morphological and physiological divergences within same group of fungi. The physiological variability even within same ecological niche raises the importance of genic markers for exploring the various aspects of diverse fungal ecology. The molecular markers developed for fungal genera in recent past were based on the conserved gene sequences but they were inadequate to distinguish between closely related strains or isolates. Of late, molecular marker based on random primers (Restriction Fragment Length Polymorphism and Random Amplified Polymorphic DNA) have been implemented for the differentiation of closely related strains, but due to their complicated methodology and low reproducibility, these hybridization and amplification based markers ran out of the race. This is invariably significant to differentiate between closely related fungal isolates or strains based on their virulence or aggressiveness or other physiological traits. Therefore, development of genic markers for a specific fungal species is requisite for establishing the correct taxonomic classification. The huge repository of genome sequences made it possible to develop genic markers for fungi. These genic markers are located either in regulatory or in functional site and are directly correlated with the trait of interest. Accordingly, genic molecular markers can be employed for the development of fungal diagnostics and deciphering their functional diversity in order to achieve marker-assisted selection for trait improvement, comparative genome mapping, and to explore fungal adaptation to different environments, etc. Hence, in the era of functional genomics, it will stand as one of the potential tool for the characterization of fungal population.