Tag: Splicing

32. Total RNA was isolated separately from cytosol and nuclei of human cells growing in a cell culture. Each sample was mixed with a purified denatured fragment of a DNA […]

31. A DNA segment was cloned into the active site region of lacZ gene and the recombinant plasmid introduced into lac T strain of E. coli and plated on a […]

30. Following statements were made about catalytic introns: A. Group I introns may undergo self-splicing by transesterification. B, Group II introns do not require any factor/protein for auto-splicing either in […]

29. In type II splicing (1) a ‘G-OH’ from outside makes a nucleophilic attack on 5′-P of first base of intron (2) a free 2’-OH of an internal adenosine makes […]

28. Although introns are not a part of the processed transcript that gets translated, they are important for several reasons. The following statements are made with reference to the possible […]

27. Following statements were made about the post-transcriptional processing of RNA in eukaryotes. A. Soon after transcription initiation, RNA polymerase II pauses -30 nucleotides downstream from the site of initiation […]

26. Which one of the following statements related to transcription and processing of mRNA is INCORRECT? (1) During prokaryotic transcription, DNA binding properties of RNA polymerase are altered by sigma […]

25. During maturation process of some RNA molecules, formation of a 2′-5′ phospho-diester bond takes place. This Following statements are made about phenomenon. A. Spliceosome mediated removal of intronic sequences […]

24. During m-RNA processing splicing is mediated by- (1) sn RNA           (2) sno-RNA (3) r-RNA             (4) t-RNA   The correct answer is (1) snRNA. Explanation: During pre-mRNA processing, splicing is mediated by the spliceosome, […]

23. Which one of the snRNAs given below base pairs with 5’splice Site of pre mRNA? (1) U1               (2) U2 (3) U4               (4) U5 The snRNA that base pairs with […]