Govt. Exams
Entrance Exams
Bt stands for Bacillus thuringiensis, a soil bacterium that produces Cry proteins toxic to lepidopteran insects. The Cry gene is inserted into cotton plants to confer insect resistance.
Bt Cotton was approved by the Indian government in 2002 and became the first genetically modified crop to be commercially cultivated in India, significantly impacting cotton production.
The Ti (Tumor-inducing) plasmid naturally transfers a portion of its DNA (T-DNA) into plant cells. Scientists use this as a natural vector to introduce desired genes into plants.
DNA ligase catalyzes the formation of phosphodiester bonds between adjacent nucleotides, sealing nicks in the DNA backbone after recombination.
Annealing temperature determines primer specificity. Optimal temperature prevents non-specific binding while allowing target amplification, crucial for PCR accuracy.
The Genetic Engineering Appraisal Committee (GEAC) under the Ministry of Environment, Forest and Climate Change evaluates and approves GMOs for environmental and food safety.
Origin of replication (ori) is essential for autonomous replication of plasmids. Without it, the plasmid cannot replicate and will be lost during cell division.
PAM sequence is essential for Cas9 recognition and binding. Without PAM (typically NGG in S. pyogenes), Cas9 cannot cleave the target DNA, ensuring site-specific editing.
Antibiotic resistance genes (like ampicillin resistance) are frequently used as selectable markers to identify successfully transformed cells that have incorporated the recombinant plasmid.
The guide RNA (gRNA) is complementary to the target DNA sequence and directs the Cas9 nuclease protein to the specific location where the DNA needs to be cut.
