Rye B chromosomes encode a functional Argonaute-like protein with in vitro slicer activities similar to its A chromosome paralog

0473677 - ÚEB 2018 RIV GB eng J - Journal Article
Ma, W. - Gabriel, T.S. - Martis, M.M. - Gursinsky, T. - Schubert, V. - Vrána, Jan - Doležel, Jaroslav - Grundlach, H. - Altschmied, L. - Scholz, U. - Himmelbach, A. - Behrens, S.E. - Banaei-Moghaddam, A.M. - Houben, A.
Rye B chromosomes encode a functional Argonaute-like protein with in vitro slicer activities similar to its A chromosome paralog.
New Phytologist. Roč. 213, č. 2 (2017), s. 916-928. ISSN 0028-646X. E-ISSN 1469-8137
R&D Projects: GA MŠMT(CZ) LO1204; GA ČR GBP501/12/G090
Institutional support: RVO:61389030
Keywords : rna-polymerase-ii * ribosomal-rna * accessory chromosomes * plant argonautes * gene-expression * evolution * transcription * pseudogenes * sequences * identification * Argonaute * B chromosomes * B-located genes * gene erosion. gene expression * pseudogenization * Secale cereale
OECD category: Plant sciences, botany
Impact factor: 7.433, year: 2017

B chromosomes (Bs) are supernumerary, dispensable parts of the nuclear genome, which appear in many different species of eukaryote. So far, Bs have been considered to be genetically inert elements without any functional genes.
Our comparative transcriptome analysis and the detection of active RNA polymerase II (RNAPII) in the proximity of B chromatin demonstrate that the Bs of rye (Secale cereale) contribute to the transcriptome. In total, 1954 and 1218 B-derived transcripts with an open reading frame were expressed in generative and vegetative tissues, respectively. In addition to B-derived transposable element transcripts, a high percentage of short transcripts without detectable similarity to known proteins and gene fragments from A chromosomes (As) were found, suggesting an ongoing gene erosion process.
In vitro analysis of the A- and B-encoded AGO4B protein variants demonstrated that both possess RNA slicer activity. These data demonstrate unambiguously the presence of a functional AGO4B gene on Bs and that these Bs carry both functional protein coding genes and pseudogene copies.
Thus, B-encoded genes may provide an additional level of gene control and complexity in combination with their related A-located genes. Hence, physiological effects, associated with the presence of Bs, may partly be explained by the activity of B-located (pseudo) genes.
Permanent Link: http://hdl.handle.net/11104/0270807