Gene Expression Profile Of The Cyanobacterium Nostoc Muscorum and its Mutant Clones By Oligonucleotide Arrays

Abstract

In the present study experimental organism was filamentous, diazotrophic, heterocystous and O2 evolving photosynthetic cyanobacterium Nostoc muscorum. The results of the studies described in the thesis are summarized below: newlineIn the parent Nostoc muscorum growth, percent survival, nitrogenase activity, photosynthetic O2 evolution and NR activity all were adversely effected under given salinity conditions. newlineIn comparison to the parent, spontaneously occurring mutant clones showing growth inhibitory effects of CsCl and TlCl and found to show more sensitivity towards all examined parameters as compared to parent strain under given salt stress. newlineThe supply of extracellular Kand#8314; mitigates the adverse effect of salt stress in parent as well as in its spontaneously occurring mutant clone. The addition of extracellular Kand#8314; at high concentration in the growth medium, restored all examines physiological parameters at their optimum level. Therefore; it is suggested that K+ in the experimental organism function as a primary osmoprotectant. newlineIn the next series of experiment we have perform DNA microarray analysis of various up regulated and down regulated genes in the mutant clones. newlineDNA microarray analysis revealed the occurrence of total 1674 genes were found to up regulated in the Cs+-R mutant clone and simultaneously total 1825 genes were found to down regulated in Cs+-R mutant. newlineSimilarly, total number of genes i. e. 2258 were found to be up regulated in Tl+-R mutant and simultaneously total number of 1848 genes were found to down regulated in Cs+-R mutant. newlineIn Cs+-R mutant up regulated genes that showed fold regulation and#8805;1.5 are 235, similarly down regulated genes with fold value and#8805;1.5 are 327. newlineLikewise in Tland#8314;-R total 327 up regulated genes in the and similarly 509 genes down regulated reported in Tland#8314;-R mutants. newline