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Antisense transcripts in Paramecium: a global strategy of
regulation of gene expression?
Simone Marker, Eva Schloter, Helmut Schmidt, Martin Simon
University of Kaiserslautern
RNA species operate on multiple levels of gene regulation, including
transcriptional and posttranscriptional mechanisms. Antisense transcripts
of coding and non-coding regions are known to have a broad
range of functions, such as repression of translation, RNAi-mediated
mRNA targeting and also transcriptional repression.
We analysed vegetative cells for presence of antisense RNA of coding
regions of single-copy, paralogous genes and genes of a multigene
family, the variable surface antigens. An RT-PCR-based method
revealed that antisense transcripts are omnipresent RNA species,
mostly covering the whole open reading frame. Moreover, presence
of intron-less and intron-containing antisense transcripts suggest different
origins and independent mechanisms of synthesis.
Since antisense transcripts hold the potential of homology-based gene
regulation, they are candidates for the regulation of paralogue and
multigene expression. Mutual exclusion of variable surface antigen
expression e.g. might be realised by RNAi-related mechanisms including
antisense RNA.
marker@rhrk.uni-kl.de
eva.schloter@gmx.de
hjschm@rhrk.uni-kl.de
msimon@rhrk.uni-kl.de
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