Impaired function of the phage-type RNA polymerase RpoTp in transcription of chloroplast genes is compensated by a second phage-type RNA polymerase.

ABSTRACT: Although chloroplast genomes are small, the transcriptional machinery is very complex in plastids of higher plants. Plastidial genes of higher plants are transcribed by plastid-encoded (PEP) and nuclear-encoded RNA polymerases (NEP). The nuclear genome of Arabidopsis contains two candidate genes for NEP, RpoTp and RpoTmp, both coding for phage-type RNA polymerases. We have analyzed the use of PEP and NEP promoters in transgenic Arabidopsis lines with altered RpoTp activities and in Arabidopsis RpoTp insertion mutants lacking functional RpoTp. Low or lacking RpoTp activity resulted in an albino phenotype of the seedlings, which normalized later in development. Differences in promoter usage between wild type and plants with altered RpoTp activity were also most obvious early in development.

SUBMITTER: Swiatecka-Hagenbruch M 

PROVIDER: S-EPMC2241911 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature