ICAR AIEEA PG 2024 - Plant Biotechnology

The Type II CRISPR-Cas9 genome editing system comprises two fundamental components: (1) the Cas9 endonuclease that creates site-specific double-strand breaks (DSBs), and (2) a synthetic single guide RNA (sgRNA or gRNA). The 5' 20-nucleotide spacer region of the guide RNA guides the Cas9 protein to a specific complementary genomic DNA target immediately upstream of a 5'-NGG Protospacer Adjacent Motif (PAM).

Proteomics is the large-scale, comprehensive analysis of the complete set of proteins expressed by a biological system (proteome). Its core applications include:
Protein mining (identification and cataloging of all proteins present in a complex sample via mass spectrometry)
Protein expression profiling (differential quantification of protein abundance across tissues, stresses, or treatments)
Mapping post-translational modifications (PTMs like phosphorylation, acetylation, ubiquitination).
In contrast, determining the atomic-resolution native 3D structure of individual proteins is the domain of structural biology (X-ray crystallography, NMR spectroscopy, and Cryo-EM), not high-throughput proteomics.

Correct scientific matching:

• Semiconservative DNA replication was famously proposed by James Watson and Francis Crick in 1953 alongside their double-helix model -> (IV)
• Reverse transcriptase was independently discovered by Howard Temin and David Baltimore in 1970 in retroviruses (for which they received the Nobel Prize) -> (I)
• CRISPR-Cas9 mediated gene editing was pioneered by Emmanuelle Charpentier and Jennifer Doudna (Nobel Prize in Chemistry 2020) -> (II)
• The primary amino acid sequence of bovine insulin was first elucidated by Frederick Sanger in the 1950s (Nobel Prize in Chemistry 1958) -> (III)