Q.18 Match the RNAs in Group I with their corresponding function in Group II
Group I Group II
(P) snRNA (1) rRNA processing
(Q) piRNA (2) RNA splicing
(R) snoRNA (3) Selected mRNAs degradation
(S) siRNA (4) Germ line protection from transposable elements
(A) P-4, Q-3, R-2, S-1
(B) P-4, Q-1, R-3, S-2
(C) P-3, Q-2, R-1, S-4
(D) P-2, Q-4, R-1, S-3
snRNA, piRNA, snoRNA, and siRNA functions match correctly with (D): P-2 (RNA splicing), Q-4 (germ line protection from transposable elements), R-1 (rRNA processing), S-3 (selected mRNAs degradation).
This CSIR NET Life Sciences matching question tests non-coding RNA roles in gene regulation and RNA processing, key for molecular biology exams. Each RNA type has a specific primary function based on established mechanisms.
Correct Matching
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(P) snRNA → (2) RNA splicing: snRNAs form snRNPs that assemble the spliceosome to remove introns from pre-mRNA.
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(Q) piRNA → (4) Germ line protection from transposable elements: piRNAs silence transposons in germline cells via Piwi proteins, preventing genomic instability during gametogenesis.
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(R) snoRNA → (1) rRNA processing: snoRNAs guide 2′-O-methylation and pseudouridylation of rRNA during ribosome biogenesis.
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(S) siRNA → (3) Selected mRNAs degradation: siRNAs trigger RISC-mediated cleavage of complementary mRNAs, enabling RNA interference for gene silencing.
Option Analysis
(A) P-4, Q-3, R-2, S-1: Incorrect—snRNA does not protect germ lines (piRNA role); snoRNA does not splice RNA (snRNA role).
(B) P-4, Q-1, R-3, S-2: Incorrect—piRNA unrelated to rRNA processing; siRNA does not splice.
(C) P-3, Q-2, R-1, S-4: Incorrect—snRNA does not degrade mRNAs (siRNA role); piRNA not for splicing.
(D) P-2, Q-4, R-1, S-3: Correct, as detailed above.
Introduction: Unlock snRNA piRNA snoRNA siRNA Functions for CSIR NET Success
Preparing for CSIR NET Life Sciences? Master snRNA piRNA snoRNA siRNA functions matching—key to RNA processing, splicing, and gene silencing MCQs. This guide explains Group I-II matches with detailed mechanisms for exam toppers.
Core Functions Breakdown
snRNA drives RNA splicing via spliceosome assembly, removing introns precisely. piRNA ensures germ line protection from transposable elements by silencing mobile DNA in gonads. snoRNA handles rRNA processing through site-specific modifications for ribosome maturation. siRNA induces selected mRNAs degradation via RISC, targeting viral or aberrant transcripts.
| RNA Type | Primary Function | Key Mechanism | CSIR NET Relevance |
|---|---|---|---|
| snRNA | RNA splicing (2) | Spliceosome formation | Pre-mRNA maturation |
| piRNA | Germ line transposon protection (4) | Piwi-mediated silencing | Genome stability |
| snoRNA | rRNA processing (1) | Methylation/pseudouridylation | Ribosome biogenesis |
| siRNA | mRNA degradation (3) | RISC cleavage | RNAi pathway |
Why This Matters for CSIR NET
These non-coding RNAs regulate gene expression at multiple levels—essential for molecular biology units. Options A-C fail by swapping roles (e.g., snoRNA ≠ splicing), confirming D as correct. Practice similar matches for 2-3% score boost.
