
Full text loading...
Category: Microbial Genetics and Molecular Biology
Splicing of tRNA Precursors, Page 1 of 2
< Previous page | Next page > /docserver/preview/fulltext/10.1128/9781555818333/9781555810733_Chap07-1.gif /docserver/preview/fulltext/10.1128/9781555818333/9781555810733_Chap07-2.gifAbstract:
This chapter reviews what is known about the mechanism of precursor tRNA splicing: (i) the tRNA substrates for the splicing reaction, (ii) the enzymes involved in removing the introns to form the mature tRNA, (iii) interactions between these enzymes and their tRNA substrates and cofactors, (iv) the organization of tRNA splicing in the nucleus, (v) the identity of splicing mutants that affect the enzymatic machinery, (vi) current knowledge about the differences and similarities of tRNA splicing in systems of various organisms, and (vii) the possible function of tRNA introns.
Full text loading...
Structure of yeast pre-tRNAs. On the left is the consensus sequence of nine different yeast pre-tRNAs (66). O = unconserved sequences in the pre-tRNA; X = regions where there are variable numbers of nucleotides. On the right is a model for the tertiary structure of these pre-tRNAs based on the crystal structure of yeast tRNAPhe (adapted from reference 1 ).
Structure of yeast pre-tRNAs. On the left is the consensus sequence of nine different yeast pre-tRNAs (66). O = unconserved sequences in the pre-tRNA; X = regions where there are variable numbers of nucleotides. On the right is a model for the tertiary structure of these pre-tRNAs based on the crystal structure of yeast tRNAPhe (adapted from reference 1 ).
Mechanism for tRNA splicing in yeast, as described in text. Splice sites are indicated by small arrows, and the intron is shown in bold. The phosphate from exogenous GTP is indicated by a filled-in triangle and the endogenous phosphate by a filled circle. CPDase = cyclic phosphodiesterase; ASTase = adenylyl synthetase; 2′-PTase = 2′-phosphatase (taken with permission from reference 97 ).
Mechanism for tRNA splicing in yeast, as described in text. Splice sites are indicated by small arrows, and the intron is shown in bold. The phosphate from exogenous GTP is indicated by a filled-in triangle and the endogenous phosphate by a filled circle. CPDase = cyclic phosphodiesterase; ASTase = adenylyl synthetase; 2′-PTase = 2′-phosphatase (taken with permission from reference 97 ).
Mechanism for removal of 2′-phosphate from spliced tRNA, as described in text. NAD+ = component I; ADP = adenosine diphosphate; and component II = phosphotransferase (adapted from reference 14 , © 1993 AAAS).
Mechanism for removal of 2′-phosphate from spliced tRNA, as described in text. NAD+ = component I; ADP = adenosine diphosphate; and component II = phosphotransferase (adapted from reference 14 , © 1993 AAAS).
Model for tertiary structure of pre-tRNA based on crystal structure of yeast tRNAPhe. Major domains of the mature tRNA are indicated, with the intervening sequence (IVS) shown in bold. The ruler indicates the measuring interaction of the endonuclease with the IVS and perhaps with a part of the mature domain (see text); the scissors indicate the 5′ and 3′ cleavage sites of the IVS (adapted from reference 2 , © 1992 AAAS).
Model for tertiary structure of pre-tRNA based on crystal structure of yeast tRNAPhe. Major domains of the mature tRNA are indicated, with the intervening sequence (IVS) shown in bold. The ruler indicates the measuring interaction of the endonuclease with the IVS and perhaps with a part of the mature domain (see text); the scissors indicate the 5′ and 3′ cleavage sites of the IVS (adapted from reference 2 , © 1992 AAAS).
Spatial model for yeast pathway of pre-tRNA splicing complex formation in vivo. See text for details. (Reprinted with permission from reference 88 . Copyright 1988, American Chemical Society.)
Spatial model for yeast pathway of pre-tRNA splicing complex formation in vivo. See text for details. (Reprinted with permission from reference 88 . Copyright 1988, American Chemical Society.)
List of yeast tRNA precursors containing introns a
a RNAs are identified by the unmodified sequence of their anticodons. ND = not determined.
List of yeast tRNA precursors containing introns a
a RNAs are identified by the unmodified sequence of their anticodons. ND = not determined.
Yeast tRNA splicing components a
a NA = not applicable; ND = not determined.
Yeast tRNA splicing components a
a NA = not applicable; ND = not determined.