ISSN:
1617-4623
Keywords:
Chlamydomonas
;
Transcription termination
;
Chloroplast transformation
;
RNA processing
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract A general characteristic of the 3′ untranslated regions of plastid mRNAs is an inverted repeat sequence that can fold into a stem-loop structure. These stem-loops are superficially similar to structures involved in prokaryotic transcription termination, but were found instead to serve as RNA 3′ end processing signals in spinach chloroplasts, and in theatpB mRNA ofChlamydomonas reinhardtii chloroplasts. In order to carry out a broad study of the efficiency of the untranslated sequences at the 3′ ends of chloroplast genes inChlamydomonas to function as transcription terminators, we performed in vivo run-on transcription experiments usingChlamydomonas chloroplast transformants in which different 3′ ends were inserted into the chloroplast genome between apetD promoter and a reporter gene. The results showed that none of the 3′ ends that were tested, in either sense or antisense orientation, prevented readthrough transcription, and thus were not highly efficient transcription terminators. Therefore, we suggest that most or all of the 3′ ends of mature mRNAs inChlamydomonas chloroplasts are formed by 3′ end processing of longer precursors.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02173973
