Q.37 Match the entries in the Group Iwith the entries inGroup II.
Group I Group II
P. Threading 1. Gene duplication
Q. FASTA 2. Fold prediction
R. Profile 3. HMM
S. Paralogs 4. k-tuple
(A) P-2, Q-1, R-3, S-4 (B) P-2, Q-4, R-3, S-1
(C) P-3, Q-4, R-2, S-1 (D) P-1, Q-4, R-3, S-2
Bioinformatics Matching: Threading, FASTA, Profile, Paralogs
Correct Answer: (B) P-2, Q-4, R-3, S-1. Threading predicts protein folds, FASTA uses k-tuples for sequence alignment, profiles power HMMs, and paralogs arise from gene duplication.
Bioinformatics Concepts Overview
These terms represent core protein analysis and evolutionary tools. Threading addresses the fold prediction challenge, FASTA accelerates database searching, profiles enable sensitive homology detection, and paralogs trace functional divergence within genomes.
Correct Matching Explained
P. Threading → 2. Fold prediction. Forces query sequences onto known 3D templates despite low homology, scoring sequence-structure compatibility to model novel folds absent from homology modeling.
Q. FASTA → 4. k-tuple. Rapid heuristic employs short word matches (k-tuples, typically 1-6 residues) to identify diagonal alignment regions, followed by Smith-Waterman refinement for sensitive database searching.
R. Profile → 3. HMM. Position-specific scoring matrices (PSSMs) from multiple alignments feed profile HMMs, modeling conserved motifs, insertions/deletions via match, insert, delete states for remote homology detection.
S. Paralogs → 1. Gene duplication. Sequence similarity from within-species duplication events; functional divergence distinguishes paralogs (neo/sub-functionalization) from orthologs (speciation).
Option Analysis
Option (A) P-2, Q-1, R-3, S-4 incorrectly assigns FASTA to gene duplication (sequence search tool) and paralogs to k-tuples (evolutionary relationship).
Option (C) P-3, Q-4, R-2, S-1 mismatches threading to HMMs (fold recognition vs statistical modeling) and profiles to fold prediction (alignment tools).
Option (D) P-1, Q-4, R-3, S-2 wrongly pairs threading with gene duplication and paralogs with fold prediction.
Computational Biology Applications
Threading/HMM-profiles solve structure prediction for orphan sequences; FASTA scans genomes for paralog families; paralog identification reveals redundancy, drug targets. Integrated pipelines (PSI-BLAST → threading → AlphaFold2) achieve atomic accuracy.
