Interrelationship amongst varieties of edible mushroom through Molecular marker Study

Abstract

The information regarding the DNA sequences of plant is very limited. When knowledge of the DNA sequence of the targeted genome is unavailable several PCR based techniques (RAPD, ITS, AFLP, SSR markers, SNP markers) are utilized to accumulate information about the genetic adaptability. Random Amplification of Polymorphic DNA is a technique by which the random segments of DNA are amplified. Short nucleotide primers (8–12 nucleotides) are used to proceed with the PCR using genomic DNA, for fragments to amplify. The primers bind somewhere in the sequence. By comparing the banding matrix the DNA patterns can be ascertained. RAPD has been utilized to characterize, trace the phylogeny of diverse plant species. Internal transcribed spacer (ITS) is to a non-functional RNA situated between structural ribosomal RNAs (rRNA) on a transcript. The sequence of rRNA precursor transcript is the 5' external transcribed sequence (5' ETS), 18S rRNA, ITS1, 5.8S rRNA, ITS2, 28S rRNA and the 3'ETS read from 5' to 3' direction. The complete sequence repeats themselves in tandem array for thousands of copies separated by regions of non-transcribed DNA termed non-transcribed spacer (NTS) or intergenic spacer (IGS). There is the presence of two ITS regions in eukaryotes. The first one located between 18S and 5.8S rRNA genes is called ITS1, while the next in the sequence is ITS2 that lies between 5.8S and 26S rRNA genes in plants. Each eukaryotic ribosomal cluster follows the sequence of the 5' external transcribed sequence (5' ETS), trailed by the 18S rRNA gene, the ITS1 and the 5.8S rRNA gene, the ITS2, the 28S rRNA gene, and finally the 3' ETS. ETS and ITS pieces are excised and rapidly degraded during rRNA maturation. In our study four different gilled mushrooms were analyzed for RAPD and ITS study.