Gene-edited Mustard

About Gene-edited Mustard: 

• India’s most significant domestically-grown oilseed is rapeseed-mustard.
• Issues with Mustard seeds
  • Mustard seeds have high levels of glucosinolates, a group of sulphur and nitrogen-containing compounds contributing to the characteristic pungency of their oil and meal.
  • Rapeseed meal is unpalatable to poultry and pigs, while having to be mixed with fodder grass and water for giving to cattle and buffaloes.
  • Besides reducing their feed intake, high glucosinolates are also known to cause goiter (swelling of neck) and internal organ abnormalities in livestock.
  • The dry seeds from the normal mustard (Brassica juncea) cultivated in India contain 120-130 parts per million (ppm or mg/kg) of glucosinolates. This is as against the sub-30 ppm levels in canola seeds.

A Gene Editing breakthrough

• The Glucosinolates are synthesised in the leaves and pod walls of mustard plants.
• Their translocation and accumulation in the seeds happens through the action of glucosinolate transporter or GTR genes.
• There are 12 such genes under two distinct classes of GTR1 and GTR2 with six copies each.
• Researchers edited 10 out of the 12 GTR genes in ‘Varuna’, a high-yielding Indian mustard variety.
• For this, they used CRISPR/Cas9 – a gene-editing tool deploying an enzyme, which acts as a “molecular scissors” to cut the DNA at precise targeted locations of the gene, and then letting the natural DNA repair process to take over.
• By doing this, their encoded proteins, responsible for transport of the glucosinolates to the seeds, were rendered non-functional.
• By lowering the glucosinolate content to the same dry seed weight concentration, the scientists have bred mustard lines whose oil and meal match the standard of canola-quality rapeseed (Brassica napus) in terms of pungency.
• The new GTR genes-edited mustard lines are transgene-free or non-genetically modified (GM).
• They contain no foreign genes like those of the Bacillus thuringiensis bacteria in cotton or Bar-Barnase-Barstar (isolated from other soil bacteria) in the GM hybrid mustard (DMH-11).

Q1) What are Proteins?

Proteins are complex organic molecules composed of amino acids, which are the building blocks of life. They are essential components of all living organisms and play a wide variety of crucial roles in biological processes.

Source: Gene-edited mustard: Less pungent, more useful