Initiation, Establishment, and Maintenance of Heritable MuDR Transposon Silencing in Maize Are Mediated by Distinct Factors

@article{citeulike:849134, abstract = {Paramutation and transposon silencing are two epigenetic phenomena that have intrigued and puzzled geneticists for decades. Each involves heritable changes in gene activity without changes in DNA sequence. Here we report the cloning of a gene whose activity is required for the maintenance of both silenced transposons and paramutated color genes in maize. We show that this gene, Mop1 (Mediator of paramutation1) codes for a putative RNA-dependent RNA polymerase, whose activity is required for the production of small RNAs that correspond to the MuDR transposon sequence. We also demonstrate that although Mop1 is required to maintain MuDR methylation and silencing, it is not required for the initiation of heritable silencing. In contrast, we present evidence that a reduction in the transcript level of a maize homolog of the nucleosome assembly protein 1 histone chaperone can reduce the heritability of MuDR silencing. Together, these data suggest that the establishment and maintenance of MuDR silencing have distinct requirements.}, author = {Woodhouse, Margaret R. and Freeling, Michael and Lisch, Damon}, citeulike-article-id = {849134}, doi = {10.1371/journal.pbio.0040339}, journal = {PLoS Biology}, keywords = {mop1, mutator, silencing, smrna, transposon}, month = {October}, number = {10}, pages = {e339+}, posted-at = {2008-11-21 19:34:12}, priority = {2}, title = {Initiation, Establishment, and Maintenance of Heritable MuDR Transposon Silencing in Maize Are Mediated by Distinct Factors}, url = {http://dx.doi.org/10.1371/journal.pbio.0040339}, volume = {4}, year = {2006} }

TY - JOUR ID - citeulike:849134 L3 - citeulike-article-id:849134 N2 - Paramutation and transposon silencing are two epigenetic phenomena that have intrigued and puzzled geneticists for decades. Each involves heritable changes in gene activity without changes in DNA sequence. Here we report the cloning of a gene whose activity is required for the maintenance of both silenced transposons and paramutated color genes in maize. We show that this gene, Mop1 (Mediator of paramutation1) codes for a putative RNA-dependent RNA polymerase, whose activity is required for the production of small RNAs that correspond to the MuDR transposon sequence. We also demonstrate that although Mop1 is required to maintain MuDR methylation and silencing, it is not required for the initiation of heritable silencing. In contrast, we present evidence that a reduction in the transcript level of a maize homolog of the nucleosome assembly protein 1 histone chaperone can reduce the heritability of MuDR silencing. Together, these data suggest that the establishment and maintenance of MuDR silencing have distinct requirements. IS - 10 JF - PLoS Biology TI - Initiation, Establishment, and Maintenance of Heritable MuDR Transposon Silencing in Maize Are Mediated by Distinct Factors VL - 4 SP - e339 KW - mop1 KW - mutator KW - silencing KW - smrna KW - transposon AU - Woodhouse, Margaret AU - Freeling, Michael AU - Lisch, Damon PY - 2006/10/01/ UR - http://dx.doi.org/10.1371/journal.pbio.0040339 ER -