Plant Genome Editing across the Central Dogma"

 

 

 The central dogma (CD) of molecular biology is the transfer of genetic information from DNA to RNA to protein. Major CD processes governing genetic flow include the cell cycle, DNA replication, chromosome packaging, epigenetic changes, transcription, post-transcriptional alterations, translation, and post-translational modifications. The CD processes are tightly regulated in plants to maintain genetic integrity throughout the life cycle and to pass genetic materials to next generation. Engineering of various CD processes involved in gene regulation will accelerate crop improvement to feed the growing world population.

                 Genome editing technologies such as CRISPR/Cas9, TALENs, and zinc finger nucleases (ZFNs) allow researchers to make precise changes to the DNA sequence of plants. By targeting specific genes, researchers can introduce mutations, deletions, or insertions to alter the function of the gene or create new traits in the plant. Advancements in CRISPR tool development have expanded the scope of genome editing to include not just DNA, but also RNA and proteins, allowing for a more comprehensive approach to modifying the central dogma processes. This includes applications in allele mining, cryptic gene activation, and introgression through de novo domestication and haploid Induction.

                Tomato yellow leaf curl virus (TYLCV), a member of the genus Begomovirus, causes widespread destruction of tomato crops worldwide. CRISPR/Cas9 system can be used for targeted interference and cleavage of the TYLCV genome. Targeting the TYLCV IR led to a significant reduction in TYLCV accumulation and disease symptoms.

               Citrus canker caused by Xanthomonas citri subsp. citri (Xcc), is severely damaging to the global citrus industry. CRISPR/Cas9-targeted modification of the susceptibility gene CsLOB1 promoter in citrus improved the resistance to canker. Deletion of the entire EBE_PthA4 sequence from both CsLOB1 alleles conferred a high degree of resistance to citrus canker.

              Genome editing is a cutting-edge technology that has significantly advanced the field of crop improvement. It involves precise modifications to the plant's genetic material to enhance desirable traits such as yield, disease resistance, and stress tolerance.

References:

 ALI, Z., ABULFARAJ, A., IDRIS, A., ALI, S., TASHKANDI, M. AND MAHFOUZ, M. M., 2015, CRISPR/Cas9-mediated viral interference in plants. Genome Biol., 16: 1-11.

 

 PENG, A., CHEN, S., LEI, T., XU, L., HE, Y., WU, L., YAO, L. AND ZOU, X., 2017, Engineering canker‐resistant plants through CRISPR/Cas9‐targeted editing of the susceptibility gene CsLOB1 promoter in citrus. Plant Biotechnol. J., 15 (12): 1509-1519.

 

PRAMANIK, D., SHELAKE, R. M., KIM, M. J. AND KIM, J. Y., 2021, CRISPR-mediated engineering across the central dogma in plant biology for basic research and crop improvement. Mol. Plant., 14 (1): 127-150.