The 5' untranslated region of the At-P5R gene is involved in both transcriptional and post-transcriptional regulation.
The steady-state level of transcripts coding for the pyrroline-5-carboxylate reductase of Arabidopsis (At-P5R) increased under salt and heat stress, mainly because of an enhanced mRNA stability. However, the At-P5R protein level was not induced, and its translation was inhibited at initiation stage and probably also at later stages. Replacement of the 5' untranslated region (5'UTR) and beta-glucuronidase (gus) fusion analysis revealed that the first 92 bp region of the At-P5R 5'UTR was sufficient to mediate transcript stabilization and translation inhibition during salt and heat stresses. Furthermore, the first 92 bp region of the At-P5R 5'UTR was also involved in transcription efficiency in a promoter-dependent manner. The results demonstrated that the stress regulation of At-P5R is complex and involves the 5'UTR which acts at three levels, partly in opposing directions.
Hua
X J
XJ
Vakgroep Moleculaire Genetica & Departement Plantengenetica, Vlaams Interuniversitair Instituut voor Biotechnologie, Universiteit Gent, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium.
Van de Cotte
B
B
Van Montagu
M
M
Verbruggen
N
N
D020121:5' Untranslated Regions; D017360:Arabidopsis / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D005966:Glucuronidase / Q000235:genetics; D006358:Hot Temperature; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D011132:Polyribosomes / Q000235:genetics; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D011762:Pyrroline Carboxylate Reductases / Q000235:genetics*; D012313:RNA; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; D012965:Sodium Chloride; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D000097502:delta-1-Pyrroline-5-Carboxylate Reductase
D020121:5' Untranslated Regions; D005966:Glucuronidase; D010940:Plant Proteins; D011762:Pyrroline Carboxylate Reductases; D012313:RNA; D012333:RNA, Messenger; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; D012965:Sodium Chloride; D014157:Transcription Factors; D000097502:delta-1-Pyrroline-5-Carboxylate Reductase; C034477:RNA primers