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10:06
Cell Type-specific Gene Expression Profiling in the Mouse Liver
Published on: September 17, 2019
Retrotransposon BARE displays strong tissue-specific differences in expression
Marko Jääskeläinen1, Wei Chang, Cédric Moisy
1MTT/BI Plant Genomics Laboratory, Institute of Biotechnology, Viikki Biocenter, University of Helsinki, PO Box 65, Viikinkaari 1, FIN-00014, Helsinki, Finland.
The New Phytologist
|September 17, 2013
Summary
The BARE retrotransposon in barley (Hordeum vulgare) replicates in specific tissues, particularly in floral structures and ovaries, suggesting germline transmission. This study reveals tissue-specific expression of the BARE capsid protein (Gag).
Area of Science:
- Plant molecular biology
- Genetics
- Genomics
Background:
- The BARE retrotransposon constitutes approximately 10% of the barley genome.
- Retrotransposon inheritance is dependent on replication site within the plant.
- BARE is actively transcribed, translated, and forms virus-like particles (VLPs).
Purpose of the Study:
- To investigate the tissue-specific expression of the BARE retrotransposon capsid protein (Gag) in barley (Hordeum vulgare).
- To elucidate the replication strategy and inheritance patterns of the BARE retrotransposon within the plant.
- To understand the transcriptional regulation and epigenetic control of BARE expression.
Main Methods:
- Immunolocalization of BARE Gag protein.
- In situ hybridization for BARE RNA and Gag expression.
- Analysis of tissue-specific expression patterns in various developmental stages.
Main Results:
- BARE Gag protein is expressed in provascular tissues and companion cells of mature vascular tissues.
- Expression is absent in the shoot apical meristem of young seedlings but appears in the developing floral spike post-transition to flowering.
- Gag shows highly specific localization in pre-fertilization ovaries, indicating potential germline transmission.
Conclusions:
- BARE expression patterns are consistent with transcriptional regulation by promoter elements.
- Ovarian expression suggests a release from epigenetic transcriptional silencing.
- This study provides the first analysis of native retrotransposon protein expression in plants, highlighting BARE's potential for germline inheritance.
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