فهرست نشریات علمی دسترسی آزاد ایران

The microalga Dunaliella salina is one of the most resilient organisms adapted to harsh environments. Research indicates that the organisms, especially plants, respond to various environmental stresses differently. D. salina has emerged as a halotolerant model organism for studying stress adaptation due to its ability to thrive under extreme salinity, light, and nutrient-deficient conditions. It produces a vital carotenoid, 9-cis beta-carotene, which is utilized in medical industry.  One of the significant interferences in stress responses is mediated by 21-24 nucleotide interfering RNAs. Malate dehydrogenase is a key enzyme involved in energy metabolism in both mitochondria and chloroplasts, and its transcription and activity regulation are highly significant. This study investigated the number of miRNA binding sites to the malate dehydrogenase transcript. The involvement of some miRNAs, including novel-m0533-3p, in energy-related metabolism has been identified. The results showed that the mitochondrial transcript had 5 binding sites and the chloroplast transcript had 1 binding site for novel-m0533-3p miRNA. The low number of miRNA binding sites to the chloroplast malate dehydrogenase mRNA sequence indicates that perhaps other gene expression regulation methods control the chloroplast malate dehydrogenase gene or probably, Chloroplastic Malat Dehydrogenase is regulated by enzyme activity, and also the 5 point of binding sites of the miRNA to the mitochondrial malate dehydrogenase mRNA, indicates that this type of gene expression regulation is more dominant. Our results suggest that miRNAs act as dynamic regulators that modulate MDH expression in a stress-type-dependent manner. These findings align with previous studies emphasizing post-transcriptional regulation as a key mechanism for microalgae adaptation to harsh environments.