Govt. Exams
Entrance Exams
Selectable marker genes confer resistance to specific antibiotics or toxins. When the transformation vector carries an antibiotic resistance gene, only cells that successfully incorporated the vector will express the resistance gene and survive on antibiotic-containing media. Non-transformed cells lack this gene and are eliminated.
The sgRNA contains a CRISPR RNA (crRNA) and trans-activating CRISPR RNA (tracrRNA) combined into a single molecule. It guides the Cas9 nuclease to the target DNA sequence through Watson-Crick base pairing, ensuring specificity of the cut.
Bt toxin (Cry proteins) forms pores in the alkaline midgut of target insects, causing cell lysis and disruption of the intestinal epithelium. This is specific to lepidopteran, coleopteran, and dipteran insects with appropriate pH and protease conditions.
Restriction endonucleases (restriction enzymes) recognize and cut DNA at specific palindromic sequences, forming sticky or blunt ends. DNA polymerase synthesizes DNA, helicase unwinds DNA, and ligase joins DNA strands.
E. coli is the primary organism used for recombinant insulin production due to its well-characterized genetics, rapid growth, and ability to produce high levels of recombinant proteins.
Homologous recombination has very low frequency in mammalian cells compared to yeast, requiring enrichment strategies and selection markers. This limitation has been overcome by CRISPR technology.
Whole-genome sequencing provides unbiased coverage of the entire genome, allowing discovery of unexpected mutations, copy number variations, and structural rearrangements not detected by targeted approaches.
TALENs consist of a modular DNA-binding domain (which recognizes specific sequences) fused to the FokI nuclease domain, allowing precise DNA cleavage at target sites.
The GEAC, operating under the MoEFCC, is responsible for appraising large-scale field trials and commercial release of genetically modified organisms in India.
The RNA-Induced Silencing Complex (RISC) uses small RNA molecules (siRNA or miRNA) as guides to recognize and degrade complementary mRNA sequences, leading to gene silencing.
