DNA is the molecular basis of life and its’ accurate maintenance is essential for the survival of all living forms. Plants are extremely successful survivors with their interesting mechanisms to precisely maintain the DNA and genome. A team of researchers at the National Centre for Biological Sciences (NCBS), Tata Institute of Fundamental Research (TIFR), Bangalore has identified the role of small RNAs (sRNAs) in the maintenance of plant genomes.
“Genome is like a book, where it encodes all the essential information called genes, in addition to pages where no information is encoded, which are known as non-coding DNA,” explains Dr P.V. Shivaprasad, the lead researcher. “However, these non-coding regions are indeed important check-points in the genome,” he adds.
Plants’ genomes have many non-coding segments that are usually not transcribed by the cellular systems. Cells utilise an elaborate system of genome bookmarking and indexing system. The researchers have discovered molecular regulation of certain book-keepers of the genome called small RNAs (sRNAs) which maintain the genome indices precisely.
“The study unravelled a novel population of sRNAs, Pol IV suppressed sRNAs, that are produced upon removal of Polymerase IV (Pol IV). These sRNAs silence the genes needed for reproductive development,” the researchers inform.
sRNAs attract many layers of epigenetic regulators to the specific regions in the genome, enabling a clear bookmarking between coding and non-coding regions. Epigenetics is the study of genomic bookmarking systems and this demarcates regions of the genome to be transcribed and silenced.
DNA is the molecular basis of life and its’ accurate maintenance is essential for the survival of all living forms. Plants are extremely successful survivors with their interesting mechanisms to precisely maintain the DNA and genome. A team of researchers at the National Centre for Biological Sciences (NCBS), Tata Institute of Fundamental Research (TIFR), Bangalore has identified the role of small RNAs (sRNAs) in the maintenance of plant genomes.
“When it comes to crop improvement or hybrid generation, the genome is like a battlefield. Due to the diverse origin and genetic variations between species, there are conflicts occurring at the genomic level. This has been a long-standing hurdle in generation of hybrids and can now be surpassed by modifying the book-keepers of the genome,” the study team mentions.
These novel arms of genome regulators - sRNAs - can read, write, or erase specific locations of the genome without compromising the health of the plant. They serve as a quick genetic toolkit to speed up breeding programmes and deliver improved crop varieties at a faster pace.
The study highlights how small molecules can tidy up larger genomes efficiently and flexibly. It also indicates how by employing the untapped regime of epigenetic switching, favourable agronomic traits can be controlled.
The findings of the study can be utilised for improving agricultural traits in a crop like rice by activating and silencing regions associated with any gene of interest by targeting epigenetic marks via sRNAs.
The study has been published in the Genome Research, Cold Spring Harbor Laboratory Press. The team consists Vivek Hari Sundar G, Chenna Swetha, Debjani Basu, Kannan Pachamuthu, Steffi Raju, Tania Chakraborty, Rebecca A. Mosher, and P.V. Shivaprasad.
India Science Wire
ISW/SM/NCBS/RNA/Eng/09/06/2023
