L-arginine influences the structure and function of arginase mRNA in Aspergillus nidulans.
Expression of the arginase structural gene (agaA) in Aspergillus nidulans is subject to complex transcriptional and post-transcriptional regulation. Arginase mRNA has a long 5'-UTR sequence. Analysis of this sequence in silico revealed its putative complex secondary structure, the presence of arginine-binding motifs (arginine aptamers) and a short intron with two potential 3' splicing sites. In this report we present evidence that L-arginine (i) binds directly to the arginase 5'-UTR; (ii) invokes drastic changes in the secondary structure of the 5'-UTR, unlike several other L-amino acids and D-arginine; and (iii) forces the selection of one of two 3' splice sites of an intron present in the 5'-UTR. We postulate that expression of the eukaryotic structural gene coding for arginase in A. nidulans is regulated at the level of mRNA stability, depending on riboswitch-mediated alternative splicing of the 5'-UTR intron.
Borsuk
Piotr
P
Institute of Genetics and Biotechnology, University of Warsaw, Pawinskiego 5A, PL-02-106 Warsaw, Poland.
Przykorska
Anna
A
Blachnio
Karina
K
Koper
Michal
M
Pawlowicz
Jerzy M
JM
Pekala
Malgorzata
M
Weglenski
Piotr
P
D001119:Arginase / Q000737:chemistry / Q000187:drug effects / Q000502:physiology; D001120:Arginine / Q000494:pharmacology*; D001233:Aspergillus nidulans / Q000187:drug effects* / Q000201:enzymology*; D001483:Base Sequence; D001665:Binding Sites; D004789:Enzyme Activation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000235:genetics; D007438:Introns; D008239:Lysine / Q000494:pharmacology; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis / Q000187:drug effects / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012996:Solutions / Q000737:chemistry; D013329:Structure-Activity Relationship
D012333:RNA, Messenger; D012996:Solutions; D001120:Arginine; D001119:Arginase; D008239:Lysine